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HomeMy Public PortalAbout480 Arsenal - Revised Stormwater Report Stormwater Report 480 Suite 3 Arsenal Street Watertown, Massachusetts Prepared for: Boylston Properties 800 Boylston Street Boston, MA 02199 Prepared by: R.J. O'Connell & Associates, Inc. 80 Montvale Ave, Suite 201 Stoneham, MA 02180 N� OF M4 o= JOHN J. yG Date: February 10, 2015 o CIVIL Revised: March 27, 2015 9�No.47T97 co 9�� G S 4 ti. ty e STORMWATER REPORT 480 Suite 3 Arsenal Street—Watertown, MA TABLE OF CONTENTS I. STORMWATER MANAGEMENT NARRATIVE 1.0 INTRODUCTION..................................................................................................... 1 2.0 SITE LOCATION AND EXISTING CONDITIONS............................................... 1 3.0 PROPOSED PROJECT............................................................................................. 1 4.0 COMPLIANCE WITH THE MA DEP STORMWATER STANDARDS ............... 2 5.0 SOILS ........................................................................................................................ 2 6.0 EXISTING DRAINAGE PATTERNS...................................................................... 3 7.0 PROPOSED DRAINAGE PATTERNS.................................................................... 3 8.0 NICHOLS AVENUE WATER QUALITY IMPROVEMENTS .............................. 4 9.0 PROPOSED DRAINAGE SYSTEM ........................................................................ 5 10.0 PEAK FLOW RATE AND VOLUME REDUCTION ............................................. 5 11.0 WATER QUALITY................................................................................................... 8 12.0 GROUNDWATER RECHARGE.............................................................................. 9 13.0 SUMMARY............................................................................................................. 10 II. FIGURES FIGURE 1: USGS LOCUS MAP FIGURE 2: SOILS MAP FIGURE 3: FLOOD INSURANCE RATE MAP FIGURE 4: NATURAL HERITAGE & ENDANGERED SPECIES PROGRAM MAP FIGURE 5: PRE-DEVELOPMENT WATERSHED PLAN FIGURE 6: POST-DEVELOPMENT WATERSHED PLAN III. HYDROLOGICAL CALCULATIONS • PRE-DEVELOPMENT • POST-DEVELOPMENT IV. MASSACHUSETTS STORMWATER REPORT CHECKLIST • DEP CHECKLIST FOR STORMWATER REPORT V. APPENDIX A • CONSTRUCTION PERIOD POLLUTION PREVENTION PLAN (CPPPP) • OPERATIONS AND MAINTENANCE PLAN • WATER QUALITY FLOW RATE AND CONTECH CDS UNIT SIZING COMPUTATIONS • MEMORANDUM FROM MCPHAIL ASSOCIATES, DESIGN PERMEABILITY RATES, DATED JANUARY 29, 2015. • FILTERRA ENGINEERING DESIGN ASSISTANCE KIT Page 1 I. STORMWATER MANAGEMENT NARRATIVE STORMWATER REPORT 480 Suite 3 Arsenal Street—Watertown, MA STORMWATER MANAGEMENT NARRATIVE 1.0 INTRODUCTION R.J. O'Connell and Associates, Inc. (RJOC) has prepared this stormwater report on behalf of Boylston Properties for the proposed redevelopment of a±8.593 acre parcel located on Arsenal Street in Watertown, Massachusetts (refer to Figure 1, USGS Locus Map). This study uses the Natural Resources Conservation Service (MRCS), formerly the Soil Conservation Service (SCS) TR-20 Computer Program for Project Formulation Hydrology and the computer program HydroCad, version 10.00 for modeling existing and proposed hydrologic site conditions. This comparative analysis of existing hydrologic conditions to post-development conditions demonstrates that the proposed condition represents a substantial improvement over the existing stormwater management conditions, and complies with the DEP's Stormwater Management Policy and the Town of Watertown's Requirements for Stormwater Drainage to the maximum extent practicable. 2.0 SITE LOCATION AND EXISTING CONDITIONS The proposed project is located on a 374,304 square foot(±8.593 acre) site located at the intersection of Nichols Avenue, Arlington Street, and Coolidge Hill Road in Watertown, Massachusetts. The land is identified by the Watertown Assessor's Office as parcel 1214 1F 3. The site is currently occupied by a one story, ±74,400 square foot metal and concrete block warehouse. The remainder of the site consists of paved parking and landscaped areas. The property is bounded on the north by Nichols Avenue, on the east and south by the Watertown Greenway Bike Path, and on the west by private commercial uses. Site topography ranges from a high elevation of 47 along a berm on the northern portion of the site to a low elevation of 32 at the southernmost part of the site. Vehicular access for the site is provided by an existing thirty foot access drive at the southern corner of the site. There is also a gated thirty foot emergency access drive in the northwest corner of the site. Stormwater runoff is collected in catch basins and treated by an oil/particle separator prior to leaving the southwest side of the site via one of three Points of Analysis (POA) further described in Section 6.0. As indicated on the site design plans dated September 21, 2000 by Cubellis Saivetz, Associates, a subsurface detention basin may exist at the southwest corner of the site 3.0 PROPOSED PROJECT The proposed project consists of the construction of a two-story office building of approximately 185,000 s.f. The project will require parking area improvements to the existing parking areas and will result in at grade parking for approximately 483 vehicles. In addition, a parking structure will be constructed in the northeast corner of the site, adjacent to Nichols Avenue with parking Page 1 STORMWATER REPORT 480 Suite 3 Arsenal Street—Watertown, MA for approximately 83 spaces. Vehicular access for the site will be from the existing southerly access road and a proposed access road at the north side of the site to Nichols Avenue. An existing emergency vehicle access at the northwest corner of the site will be relocated to the northeast corner of the site to maintain a connection to Nichols Avenue. 4.0 COMPLIANCE WITH THE MA DEP STORMWATER STANDARDS The redevelopment program includes a comprehensive stormwater management system that will collect, pre-treat, treat, and control stormwater runoff in conformance with the DEP's Stormwater Management Policy and the Town of Watertown's On-Site Drainage Requirements. As a result of controlling and containing runoff on-site from all storms up to and including the 25-year event, Standards 1, 2, 3, 4, and 7 are fully complied with. Standard 6 does not apply since the project is not located within a Zone II or Interim Wetland Protection Area of a public water supply and stormwater does not discharge to any other critical area. A Construction Period Pollution Prevention Plan (CPPPP) addressing erosion, sedimentation, and other pollutant sources is included in Appendix A in compliance with Standard 8 and an Operation and Maintenance Plan has been developed that outlines inspection and maintenance requirements to ensure the proper, long-term operation of the stormwater management system and includes an illicit discharge compliance statement in compliance with Standards 9 and 10. 5.0 SOILS The Natural Resources Conservation Service (MRCS) online soils database classifies the underlying soils on the site as "Urban Land". McPhail Associates, LLC performed twenty three borings and three test pits in various locations on site. Using the information provided by McPhail Associates, the underlying soils on the majority of the site were classified as belonging to Hydrologic Soil Group A, except for a small portion of the west side of the site which is classified as Group B (see attached"Memorandum" from McPhail Associates, LLC dated January 29, 2015 Appendix A). Rawls infiltration rates, determined by McPhail Associates, were used in the design of the subsurface infiltration systems and the water quality infiltration swale (see table, below). Design Permeability Rates (Rawls Rates) Site Location Texture Class Design Permeability (in./hr.) East Loamy Sand 2.41 Southeast Sand 8.27 Southwest Loamy Sand 2.41 West Loam 0.52 Page 2 STORMWATER REPORT 480 Suite 3 Arsenal Street—Watertown, MA 6.0 EXISTING DRAINAGE PATTERNS The existing site consists of three drainage catchment areas based on topography, drainage networks and three discharge points from the site or Points of Analysis (POAs). See Figure 5, Pre-Development Watershed Plan. Watershed EX-1: This 2.56 acre watershed is comprised of drive aisles, landscaped areas, and the western portion of the building roof(f98,314 s.f. of total impervious area). Stormwater runoff within this watershed sheet flows to one of two catch basins, or through the building roof drain system and discharges untreated, off site through an 18-inch diameter drain at POA-A on the west side of the site. Watershed EX-2: This 0.81 acre watershed is comprised of a portion of the paved parking area and landscaped areas (±32,897 s.f. of total impervious area). Stormwater runoff within this watershed sheet flows to one of two catch basins, and then may travel through a subsurface detention basin before being discharged on the west side of the site through a 12-inch diameter drain, POA-B, south of POA-A. Watershed EX-3: This 4.56 acre is comprised of drive aisles,paved parking areas, landscaped areas, and the eastern portion of the building roof(±169,352 s.f. of total impervious area). Stormwater runoff sheet flows to one of eight catch basins, or through the building's roof drains and is treated by an oil/water separator located at the southwest corner of the site. From the separator, it then discharges off site through an 18-inch diameter drain at POA-C in the southern corner of the site. 7.0 PROPOSED DRAINAGE PATTERNS The site was divided into six watersheds based on the proposed site layout, grading, drainage networks and three points of analysis (refer to Figure 6, Post-Development Watershed Plan). The study area increased from existing conditions by 0.17 acre due to changes in grading and site layout. Watershed PR-1: This 1.58 acre watershed consists of the top level of the parking structure, drive aisles,paved parking areas, and landscaped areas (±57,121 s.f, of total impervious area). Stormwater on the lower level of the parking structure drains to one of three catch basins and through an oil/water separator before discharging to the sanitary sewer in accordance with the plumbing code. Runoff from the remainder of the watershed sheet flows to one of three catch basins equipped with deep sumps and hoods, in the paved parking areas, or to one of three area drains in the landscaped area on the north side of the building before being treated in an oil/particle separator and discharging into Subsurface Infiltration Basin 3 (SSI-1). SSI-1 is designed to retain and infiltrate runoff from the 25-year storm event. An overflow pipe from SSI- 1 discharges into the existing 18-inch drain along the east side of the site that exits at the south corner of the property(POA-C). Page 3 STORMWATER REPORT 480 Suite 3 Arsenal Street—Watertown, MA Watershed PR-2: This 4.65 acre watershed includes the building roof, drive aisles, paved parking areas, landscaped areas, and the main entrance patio area(f174,874 s.f. of total impervious area). Runoff from the roof flows into the building roof drain system and directly into Subsurface Infiltration Basin 2 (SSI-2). Stormwater from paved and landscaped areas sheet flows into one of six catch basins equipped with deep sumps and hoods, then through an oil/particle separator before discharging into SSI-2. An outlet control structure controls discharge from SSI-2 into the existing drainage system, exiting the site at POA-A. Watershed PR-3A: This 0.53 acre watershed is comprised of drive aisles,paved parking areas, landscaped areas, and pedestrian paths around the building(f16,596 s.f. of total impervious area). Stormwater runoff sheet flows to either a catch basin or directly into the sediment forebay. Runoff from the paved areas is treated by a catch basin equipped with a deep sump and hood prior to entering the sediment forebay. Overflow from the forebay discharges into the water quality/infiltration swale, and then into SSI-2 via an area drain located at the southern end of the swale. Watershed PR-313: This 0.51 acre watershed is comprised of landscaped areas and pedestrian paths around the building (±5,680 s.f. of total impervious area). Stormwater runoff sheet flows directly into the water quality/infiltration swale. Overflow from the water quality/infiltration swale discharges into SSI-2 via an area drain located at the southern end of the swale. Watershed PR-4: This 0.61 acre watershed is comprised of drive aisles,paved parking areas, and landscaped areas (±24,982 s.£ of total impervious area). Stormwater from the paved parking areas sheet flows into one of two catch basins before discharging into Subsurface Infiltration Basin 3 (SSI-3). SSI-3 is designed to retain and infiltrate the runoff from the 25-year storm event. An overflow pipe connects to the existing drainage system at and eventually leaves the site at POA-C. Watershed PR-5: This 0.21 acre watershed is comprised of paved parking and landscaped areas (±8,286 s.f. of total impervious area). Stormwater runoff from this watershed sheet flows to an existing catch basin and is treated by the existing, on-site oil/water separator before exiting the site at POA-C. 8.0 NICHOLS AVENUE WATER OUALITY IMPROVEMENTS The proponent has agreed to water quality improvements along Nichols Avenue upstream of the existing drainage system. Stormwater from Nichols Avenue will now enter one of three Filterra Bioretention Systems as manufactured by Contech. These Filterra systems provide 85% TSS removal, as well as Phosphorous,Nitrogen, oil, grease, and other pollutant removal (see attached "Engineering Design Assistance Kit"by Filterra in Appendix A). From these bioretention systems, clean stormwater will flow into either a 24-inch perforated pipe encased in stone for infiltration, or directly into a proposed rain garden adjacent to the emergency access drive in the northeast corner of the site. In the case of a low frequency storm, the infiltration pipe will Page 4 STORMWATER REPORT 480 Suite 3 Arsenal Street—Watertown, MA overflow into the proposed rain garden. An area drain is provided as an overflow for the rain garden, which then enters the existing drainage system in Nichols Avenue. 9.0 PROPOSED DRAINAGE SYSTEM The proposed drainage conveyance system consisting of catch basins with deep sumps and hoods, manholes and high density polyethylene (HDPE)pipe is sized to collect and convey runoff on site for the 25-year storm event. 10.0 PEAK FLOW RATE AND VOLUME REDUCTION Peak runoff flow rates were determined under existing and proposed conditions for the 2-year, 10-year, 25-year and 100-year design frequency storms. The standard, 24 hour, Type III rainfall distribution was used in the analysis. The NRCC (Cornell)rainfall amounts used were 3.2, 4.9, 6.2 and 8.9 respectively. Below is a description of each POA used. POINT OF ANALYSIS DESCRIPTION POA-A 18"drain pipe receiving stormwater from the northwest portion of the site and leaving the site at the west property line POA-B Drain pipe receiving stormwater from the southwest portion of the site and leaving the site at the west property line POA-C 18"drain pipe receiving stormwater from the east portion of the site and leaving the site at the west property line The site was divided into subcatchment areas for the pre and post-development conditions, based on topography, drainage networks and the POA. A total of three drainage catchment areas were analyzed for the pre-development condition and six catchment areas were analyzed for the post- development condition(refer to Figures 5 and 6). Technical Release 20 (TR-20) methodology was utilized to determine weighted curve numbers (CNs) for each pre and post-development catchment area. Weighted CNs were based on ground cover type and hydrologic soil group (HSG). The time of concentration (Tc's) for each of the existing and proposed watersheds was determined. A minimum travel time of 6 minutes was used in the analysis. The catchment area, CN, Tc values and the 24 hour rainfall were then used to generate hydrographs using HydroCad 10.0, a computer program that develops a hydrograph based on the TR-20 methodology and computes peak discharges from rainfall runoff for urban and rural watersheds. The tables below summarize peak pre to post-development runoff rates and volumes of discharge at each POA. Page 5 STORMWATER REPORT 480 Suite 3 Arsenal Street-Watertown, MA Point of Analysis A Table Al Stormwater Runoff Rates Summary Existing Flow Proposed Flow Change o Reduction /o Storm Frequency (cfs) (cfs) (cfs) 2 Year 6.52 0.00 -6.52 100% 10 Year 10.92 0.00 -10.92 100% 25 Year 14.26 0.00 -14.26 100% 100 Year 21.11 6.81 -14.3 68% Table A2 Stormwater Runoff Volumes Summary Existing Volume Proposed Volume Change o Storm Frequency /o Reduction (ac-ft.) (ac-ft.) (ac-ft.) 2 Year 0.48 0.00 -0.481 100% 10 Year 0.83 0.00 -0.828 100% 25 Year 1.10 0.00 -1.098 100% 100 Year 1.67 0.46 -1.211 73% Point of Analysis B Table B 1 Stormwater Runoff Rates Summary Existing Flow Proposed Flow Change o Reduction /o Storm Frequency (cfs) (cfs) (cfs) 2 Year 2.27 0.00 -2.27 100% 10 Year 3.65 0.00 -3.65 100% 25 Year 4.69 0.00 -4.69 100% 100 Year 6.84 0.00 -6.84 100% Table B2 Stormwater Runoff Volumes Summary Existing Volume Proposed Volume Change o Storm Frequency /o Reduction (ac-ft.) (ac-ft.) (ac-ft.) 2 Year 0.17 0.00 -0.172 100% 10 Year 0.29 0.00 -0.285 100% 25 Year 0.37 0.00 -0.372 100% 100 Year 0.55 0.00 -0.554 100% Page 6 STORMWATER REPORT 480 Suite 3 Arsenal Street—Watertown, MA Point of Analysis C Table C1 Stormwater Runoff Rates Summary Existing Flow Proposed Flow Change o Reduction /o Storm Frequency (cfs) (cfs) (cfr) 2 Year 10.83 0.56 -10.27 95% 10 Year 18.69 0.92 -17.77 95% 25 Year 24.68 1.18 -23.5 95% 100 Year 36.99 4.54 -32.45 88% * The drainage area entering POA-C is 4.56 acres under existing conditions, and the area contributing 25-year storm flow or less to POA-C under proposed conditions is 0.21 acres (95%reduction). The 0.21 acres flow directly into an existing double catch basin then through an oil water separator before flowing o$site. Table C2 Stormwater Runoff Volumes Summary Existing Volume Proposed Volume Change o Storm Frequency /o Reduction (ac-ft.) (ac-ft.) (ac-ft.) 2 Year 0.79 0.04 -0.749 95% 10 Year 1.40 0.07 -1.326 95% 25 Year 1.87 0.09 -1.78 95% 100 Year 2.88 0.40 -2.478 86% * The drainage area entering POA-C is 4.56 acres under existing conditions, and the area contributing 25-year storm flow or less to POA-C under proposed conditions is 0.21 acres (95%reduction). The 0.21 acres flow directly into an existing double catch basin then through an oil water separator before flowing offsite. Page 7 STORMWATER REPORT 480 Suite 3 Arsenal Street—Watertown, MA 11.0 WATER OUALITY The redevelopment program includes suitable measures to pre-treat runoff from paved parking lot areas prior to discharging into the proposed subsurface detention systems. Best Management Practices (BMPs)have been incorporated into the design which results in a significant reduction in annual stormwater pollutant loads from the site. Through the use of structural and non- structural BMPs, the water quality volume from the parking lot will undergo treatment to the maximum extent practicable. The following BMP's were selected to remove 80% of the average annual post-construction load of Total Suspended Solids (TSS) from stormwater runoff. Refer to the TSS Removal Calculation Worksheet Table (below) and the Contech CDS Unit Sizing Computations in Appendix A. • Street Sweeping Sweeping will be performed routinely within the parking lot and driveway areas to reduce sediments and trash before they can enter the catch basins. • Deep Sumn Hooded Catch Basins Stormwater runoff from proposed pavement areas will be directed via curbing and site grading to catch basins with deep sumps and hooded outlets. Catch basins will trap and remove sediment and larger particles from the stormwater and improve the performance of subsequent BMP's. The catch basin sumps will be a minimum of 4' in depth and a regular inspection and cleaning schedule will be followed to ensure optimal effectiveness. When properly constructed and maintained, catch basins with deep sumps and hooded outlets are quite effective in reducing the sediment and pollutant load in runoff. • Hvdrodvnamic Oil/Particle Separator(CDS unit) Stormwater runoff from parking areas will drain through hydrodynamic oil/particle separators. Hydrodynamic oil/particle separators are underground concrete structures that employ a helical flow pattern that enhances trapping and containment of pollutants and provides effective removal of settleable solids and floating debris from stormwater runoff. In conjunction with deep sump catch basins, the required 44% of the total suspended solids are removed prior to discharge to an infiltration BMP for treatment. • Sediment Forebav and Water Ouality/Infiltration Swale Runoff from a portion of the parking lot will be directed to a sediment forebay and water quality/infiltration Swale using soil and vegetation to remove pollutants from stormwater runoff. Any overflow from the swale will discharge into Subsurface Infiltration System 2 for additional treatment. • Subsurface Infiltration Svstems Pre-treated runoff from paved parking areas and the building roof will be directed to one of three subsurface infiltration systems which are sized to retain and infiltrate runoff from the 25-year storm event into the underlying soil where 80% TSS removal efficiency is achieved. Page 8 STORMWATER REPORT 480 Suite 3 Arsenal Street—Watertown, MA TSS Removal Calculation Worksheet Table TSS Removal Treatment Train Sweeping- Catch Basins—Particle Separators—Infiltration System BMP TSS Removal Starting TSS Amount Remaining Load (A) Rate Load Removed (BxC) (C-D) (B) (C) (D) (E) Street Sweeping 0.05 1.0 0.05 0.95 Deep Sump CB's 0.25 0.95 0.24 0.71 CDS Unit (Oil/ 0.25 0.71 0.18 0.53 Particle Separator Subsurface/ 0.80 0.53 0.42 0.11 Infiltration System Total TSS Removal= Summation of(D) = 89% 12.0 GROUNDWATER RECHARGE Because the amount of open space/landscaped area is increased under redeveloped as compared to existing conditions by approximately four percent, groundwater recharge on site is increased. Furthermore, the stormwater runoff from the site is being collected and infiltrated into the ground up to the 25 year storm event via the three proposed subsurface infiltration systems, which will greatly increase the groundwater recharge volumes under redeveloped conditions. Groundwater Recharge Provided: BMP Elevation Recharge Volume Provided Subsurface Infiltration System— 1 28.0' —34.0' 19,446 c.f. Subsurface Infiltration System—2 30.0' 34.0' 54,721 c.f. Subsurface Infiltration System—3 30.0' —32.5' 6,822 c.f. Total Volume Provided 86,981 c.f. Check Drawdown Time: As per the Massachusetts Stormwater Handbook, the minimum required recharge volume should infiltrate within 72 hours. The drawdown analysis for the Static Method is performed by selecting the Rawls infiltration rate (provided in the Handbook) for the existing site soils in the areas where recharge is proposed. The existing soil beneath the recharge areas have been classified as HSG-A, with varying infiltration rates per McPhail's recommendations. Page 9 STORMWATER REPORT 480 Suite 3 Arsenal Street—Watertown, MA T time = R„ drawdown (K)(Bottom Area) Where: R„= Storage Volume K= Saturated Hydraulic Conductivity (from Rawls Rate table Massachusetts Stormwater Handbook Table 2.3.3) Bottom Area=Bottom Area of Recharge BMP Subsurface Infiltration Svstem— 1 19,446 c.f. Timedrawdown = = 20.0 hours (2.41 in./hr.) 1 f t/12 in. (4,836 s.f.) Subsurface Infiltration Svstem—2 T imedrawdown = 54,721 c.f. = 12.1 hours (2.41 in./hr.) 1 f t/12 in. (22,517 s.f.) Subsurface Infiltration Svstem—3 Timedrawdown = 6,822 c.f. = 7.0 hours - (2.41 in.1hr.) 1 f t 112 in. (4,830 s.f.) 13.0 SUMMARY The stormwater management system for the proposed redevelopment includes measures for collecting, controlling and treating stormwater runoff from the site. The drainage improvements proposed herein will significantly reduce stormwater runoff and volume leaving the site, increase groundwater recharge and significantly improve storm runoff water quality. Initiating regularly scheduled pavement sweeping and the drainage system maintenance program outlined in the Operations and Maintenance Plan will ensure the long term performance of the stormwater management system. The proposed measures under the redeveloped conditions represent a substantial improvement over existing stormwater management conditions and satisfy the requirements and objectives of the Massachusetts Stormwater Management Policy and the Town of Watertown On-Site Drainage Requirements. Page 10 II. FIGURES O Q �; �o \ Q ao ' IN .% - CM �o ST h J I Wate own ._..� e . ��� �\ Fillippel� 50 LAUREL �o LA \ z I �� PlaY9. 1tA ti �A,�sE t� S:a v rin s? NAL.,ST S i T IIE I . Pond /w0�LEYiAVEJ- =i 50 c�— R \Es.RivER� ® 20 MIDDLESEX-CO,� Whanles River '��` �� SUFFOLKKcCO � ,; ;aneull rToo ; �� �� - CO :Z5Mi in All 1,000 0 500 1,000 2,000�`\ —. Lug = GRAPHIC SCALE IN FEET <N` V� \ �y # ��P'�r—,n. P.J. by., Project Nome: Oroeiog Name: Droerinq No.: Designetl by M Drawn by ems RJO'Cor aEu 480 SUITE 3 MM LOM 1 FIG.Cbeckea by RlS !ASSOCIATES,INC. ARSENAL STREET u.D 1 1 scale 1'=1,000' ,.Y- Date 02/10/2015 WATERTOWN,MA No. RENSION DATE/ ♦ �••,•,.3140�� "*- 4II74 Copyright©2015 by R J.O'Connell&A..—ot-,Inc Drawing name: G\MA\Watertown\Boylston Properties\480 Arsenal Street\Reports\Stormwater Report\Figures\14074-FIG 1 USGS Locus Map.dwg Feb 06, 2015 - 12:11 pm 3 Hydrologic Soil Group—Middlesex County,Massachusetts 3 322150 322220 322290 322360 322430 322500 322570c 42°22'9"N 42°22'9"N ti Yukon Ave N ■ A 0 o � � O o n N N O O � 1 a � ' o a o 42°21'S0"N 42°21'50"N 322150 322220 322290 322360 322430 322500 3 3 i. Map Scale:1:2,810 if printed on A portrait(8.5"x 11")sheet 1eters N 0 40 80 160 240 Feet 0 100 200 400 600 Map projedion:Web Mercator Comer coordinates:WGS84 Edge tics:UTM Zone 19N WGS84 USDA Natural Resources Web Soil Survey 11/10/2014 Conservation Service National Cooperative Soil Survey Page 1 of 4 Hydrologic Soil Group—Middlesex County,Massachusetts MAP LEGEND MAP INFORMATION Area of Interest(A01) p C The soil surveys that comprise your AOI were mapped at 1:25,000. Area of Interest(A01) 0 C/D Warning:Soil Map may not be valid at this scale. Soils D Soil Rating Polygons Enlargement of maps beyond the scale of mapping can cause A p Not rated or not available misunderstanding of the detail of mapping and accuracy of soil line placement.The maps do not show the small areas of contrasting A/D Water Features soils that could have been shown at a more detailed scale. Streams and Canals B Transportation Please rely on the bar scale on each map sheet for map 0 B/D t++ Rails measurements. 0 C r-„r Interstate Highways Source of Map: Natural Resources Conservation Service Web Soil Survey URL: http://websoilsurvey.nres.usda.gov 0 C/D US Routes Coordinate System: Web Mercator(EPSG:3857) 0 D Major Roads Maps from the Web Soil Survey are based on the Web Mercator 0 Not rated or not available Local Roads projection,which preserves direction and shape but distorts distance and area.A projection that preserves area,such as the Soil Rating Lines Background Albers equal-area conic projection,should be used if more accurate " A Aerial Photography calculations of distance or area are required. " x A/D This product is generated from the USDA-NRCS certified data as of B the version date(s)listed below. B/D Soil Survey Area: Middlesex County,Massachusetts Survey Area Data: Version 14,Sep 19,2014 " r C Soil map units are labeled(as space allows)for map scales 1:50,000 "-0 C/D or larger. " x D Date(s)aerial images were photographed: Mar 30,2011—May 1, " r Not rated or not available 2011 Soil Rating Points The orthophoto or other base map on which the soil lines were 0 A compiled and digitized probably differs from the background imagery displayed on these maps.As a result,some minor shifting p A/D of map unit boundaries may be evident. ■ B ■ B/D uSDA Natural Resources Web Soil Survey 11/10/2014 Conservation Service National Cooperative Soil Survey Page 2 of 4 Hydrologic Soil Group—Middlesex County, Massachusetts Hydrologic Soil Group Hydrologic Soil Group—Summary by Map Unit—Middlesex County,Massachusetts(MA017) Map unit symbol Map unit name Rating Acres in AOI Percent of AOI 602 Urban land 32.8 99.4% 631C Charlton-Urban land- A 0.2 0.6% Hollis complex,3 to 15 percent slopes,rocky Totals for Area of Interest 33.0 100.0% Description Hydrologic soil groups are based on estimates of runoff potential. Soils are assigned to one of four groups according to the rate of water infiltration when the soils are not protected by vegetation, are thoroughly wet, and receive precipitation from long-duration storms. The soils in the United States are assigned to four groups (A, B, C, and D) and three dual classes (A/D, B/D, and C/D). The groups are defined as follows: Group A. Soils having a high infiltration rate (low runoff potential)when thoroughly wet. These consist mainly of deep, well drained to excessively drained sands or gravelly sands. These soils have a high rate of water transmission. Group B. Soils having a moderate infiltration rate when thoroughly wet. These consist chiefly of moderately deep or deep, moderately well drained or well drained soils that have moderately fine texture to moderately coarse texture. These soils have a moderate rate of water transmission. Group C. Soils having a slow infiltration rate when thoroughly wet. These consist chiefly of soils having a layer that impedes the downward movement of water or soils of moderately fine texture or fine texture.These soils have a slow rate of water transmission. Group D. Soils having a very slow infiltration rate (high runoff potential)when thoroughly wet. These consist chiefly of clays that have a high shrink-swell potential, soils that have a high water table, soils that have a claypan or clay layer at or near the surface, and soils that are shallow over nearly impervious material. These soils have a very slow rate of water transmission. If a soil is assigned to a dual hydrologic group (A/D, B/D, or C/D), the first letter is for drained areas and the second is for undrained areas. Only the soils that in their natural condition are in group D are assigned to dual classes. Rating Options Aggregation Method: Dominant Condition LJSDA Natural Resources Web Soil Survey 11/10/2014 Conservation Service National Cooperative Soil Survey Page 3 of 4 a ay�4 COI G - PANEL 0557E ma E���E Z. FIRM 3 16 y m 0 �Q'�E J O o FLOOD INSURANCE RATE MAP LLI �OQ ��C MIDDLESEX COUN•1 1, Q +rr vQDMASSACHUSEWS �P 1; (M.L J RISDICnONS) 0 rn H7 a lu �° 0 ter w CyO�S�I �- mttz r,AN ��( t�� PANEL 557 OF 656 OT �ENGE , Q Fo K SIRE T,' O - PM `OBNYP INDEX FOR FIRM PANEL LAYOUT) A. �9O�T a Z CRAWFORD STREET �0 0( CoyWNrY NLAMEg PANE L SUM uunair t c n a}AD r.. oss7 E IAILRICNt,IOAN OF > d O a E y BEET FFp m � COOLIDGE HILL � ZONE CD No b U- TM Mp N-b.,Yaws Mbn, w M z F -1 �� ��S" J Z zoI V E x --- CD uiW~PIKt^i"P w a,."C—MY NI • / ` f110'A,1•lq,.010ub De II,M m nsvance appKanms fa 1M LLI �O i aRAFT `�� Town of otp••T„F MAP NUMBER PUTNAM STREET rn p`1 L ��. Designed by: BMS ,�` Wattertown �''ADL 7 25017C0557E Drawn by: BMS OQ� �� 25o7rq�3 ® EFFECTIVE DATE CleclScale ed by: RWS5oo' SPRUCE STREET LAUREL STREET 1 , gERKEIEY JUNE 4,2010 Date: 02/10/2015 r Federal Emergenc,Nianagement Agenq CYPRESS STREET % / 3 LEGEND ? STREET � t t ��QG Prepared For: SPECIAL%ANNUAL HAZARD AREAS SUBJECT TO]NUNDAT11 r: k.� Y U K O N BY THE 1%ANNUAL CHANCE FLOOD :� CHAR ES The 1%VI rload(1001-IIboOI,also,rows as fAe eme fbW.n Oc rood t INS n 11v �, AYEN U h ` ' �'. G REENOUG H -Made d tar q eaNled a e oe0ed m are reI Tee sped-Nam w Id A a•n tl e. ct BOULEVARD arm sllpaa m II w me 1%enlxlN dMffoe hood. Nms d soacbl clod-Itetdl0 mdu0e; $pj:E-STQN PRDPEHl.Y I Zum,A.AE.AN.AD.AR.4%.V.•nd VE The Mee Fbod Nevalm It Ue wattr,som. ovaban or Me l%mnlMl av"III 800 BOYLSTON STREET .� e ' • ZONEA Fb"--F•nd Ekv&-dehen-ed SUITE 1390 (� BOSTON, MA 02199 RA rf ROAD y� _ zorFE AE Ba a Fb9a E tRt Mrs ddemnned. PHONES 617-262-4646 ZONE AN Abed dI of 1 to 1 feet(-Ay.m,oY V,mIgl,!Mx nem .y �,Z ZONE AO Food OEM,d 110 3 faN tusuaW 010N fbw a1 Joany WWI;serape / ZONE X EtY Aow dte ,ef. gRSENgL STREE I 3 .1 eepI.ddmrNlel. For anNd d NK-W Im&AWq,.etaAle•.Iso ./ admn.4t. Prepared By: C+N SM,o ZONE art SLecal Fba/aura Ald(ol,lcdr a0ttttad rmm uc IT e+a.la thelKe bF a rbOd coaUa,yvgn Itet ws subeQ,d�tN atod,Icd,Zone AR. RJO I C ONNELL u,,NM.llnt"IMmI Kled-MIDI systln N b"_WM w P-0- s ( r m ZON E X vdtemM Rdm tro l%aMUL a Ixt a pall fboa m � t - &Assoctn'rEs,INC. ZONE A" Arta 10 to Maaa,I Ran 1%Maul aMret rl0aa M A FIMal IIOW / CIVIL ENGINEERS,SURVEYORS p,aeaxnt .dam i,9e Fqd EeaWd N a A ) � Oelermriel 8 LAND PLANNERS r _ 80 M'E T`A, E FVE rr{r I�FF, ZONE V Ele ILOe SMe NRR s�FlPOty 1168V(WM iWORI;RD RY-0 fbdd Sro N En n81 79 0180 Y 7� •/�`-"t '� �, Y � EkVdlkvG delUrlwlm. FAOXN 181 zee-onaeo —" 4 : 1~ gRSENgL ZONE VE rm9al kw rae w,tn e O ,N s I I—dttbn): ene Ft d t• Z _ _ _ STREET 4 Ee�eM^deP� ad / F;• i 1 6 = FLOODWAY AREAS IN ZONE AE / tl,e Ik!a)xnY�,tt a rhelray d-WeI I PYa In A R-t f/.Ydpten man V.,1 nW to lUx Rae o Town of ,4�� - � --• �Q • — Project Name: - A a tnoac.YM:nt so dxt Uve 14..emwl,Mrce Rm0:�G r.rtul nilrwA�ubteFrCY mM•e• 3 f a#ertOWn x oJ`�J ZONE X ZONE AEA OTHER FLOOD AREAS 480 SURE 3 ZONE x Aram d a IYMI allloe Ibdd:,-..,..,,�. :��mm ROMI w,mo . ARSENAL STREET a ` 2-S�Z�Z�3 J�� AreraVe aePlRf 0f leaf IRan i foo�. .. ..,..Ie„UW ZO N E X Sao 1 OTHER ARR a EAS,•n0 a sa V oOeRld L, h 0!adM WATERTOW MA 1 C�illl•�L'� R11'L'1' - ZONE x •rcas adem,nA to x odt,ge u,c 0.7%rvHe1^�rqe fba11, 5 <} s ® COASTAL BARRIER RESOURCES SYSTEM(CBRS)AREA,, rt OTHERWISE PROTECTED AREAS(OPAs) Drawing Name: 2U Lti [r �'�tl ' ®RS be6,W Oft,ue-WV MAIW 11pII0SVIIFlWdNarardAIAb- / ' 1%Pnnd Ofna arbOLI routden 0 2%&1W cFW Ke f m V W,eandar FLOOD PROFILE BASELINE Zmeppamary INSURANCE _ RATE MAP O ............... a w,,cNA an Sp od Ctw ro Im" Nm -'a,- and —0a11101O`M"r e•sd YPbW Maud a/ Olreenl BeF� J _ •1�.. _ Flood E*vwx-,flow deatr a(I,Fbtl1G \ / ,`{ `'�" '"^ •, �.: �`.•;. • — — , ^-••••sr�^^�� 6!X Fbm E*Rtm Ina am wil elRedOn m fee• - rti �•, �• y F1'r71 11x Plow EIev lak.MMle IFNaffl MMn.Vn!:a A_ / \ v a a►+- ^f� Drawing No.: o � % 1 •Rel^erltea In ft*W Amen-vemrtl Olt-a 19W < A FIG 3 � X � A i0 __----0 TrueaLt lr,e 500 0 250 500 1,000 87 o74s az zrso • y �)IN +xdl Ant�R ■ o _=�"'•-'- -s•�`.. _i+•- . - '76-N l0oamcttr emna,al n+tvcre Merzav�and•,Yuec.roc 29 rn1 +' \ Project No..,F w FT Ea 600 14074 / 000 W fnal N vaMev-.W KRu�Role Pyle:Pwnlxa a� GRAPHIC SCALE IN FEET ,. CM V.JKt- rntF1F5ZONE700nlMm ribxnmTl �" p - Copyright©2015 by R J O'Connell&Associates.Inc dA N Active Data Layers r � + A Check all Unc hec k a8 Remove .Rk �?I i•r. .. ;',;; If 2013 Color Drthos (USGS) ,� {] ✓ NHESP Priority Habitats of Rare Species , } V Tax Parcels for Query ♦ Detailed Features LWr H 411" G f l # _ � Tax Par-,els � ►*"� 1 Legend NHESP Priority Habitats of Rare Species SITE w � Is I • Designed by: BMS - ♦ �€ • ----;,,,,__;,._, ♦ Drawn by: BMS r 31- Ir ' Checked by: RWS t ♦♦ Scale: 1 11 500' < ! Date: 02/10/2015 - 4f ' ,♦ r1'}' ` Prepared For: • % 16 t � ,� 41FIf _� h �{ f s+ $bYI.SiQN PRDPEHl. a a 800 BOYLSTON STREET SUITE 1390 BOSTON, MA 02199 PHONES 617-262-4646 d +� � 1 "RR►► F � / N a � .r R ■ � r T Prepared By: c� RJOrCONNELL ' &ASSOCIATES,INC. 7- }�4 CIVIL ENGINEERS,SURVEYORS 1. &LAND PLANNERS 1. 80 MO TVALE AVE .21 SHONE,HAM.781 MA 02180 � FAONE81-279-0173 BO a Project Name: .f • IL 480 SUITE 3 ARSENAL STREET WATERTOWK MA o 7 ♦w. 9Wa IL - s aE '" Drawing Name: AL Ilk _i NATURAL HERITAGE Jt 01 # ENDANGERED SPECIES # � , PROGRAM MAP 01 41 aa * a - • t ' t � Drawing No.: _ �- ;�1,.: . �. - FIG 4 500 0 250 500 1 ,000 + ~^ -- ` rna _ .o+it Project No.: 14074 GRAPHIC SCALE IN FEET or \ / T p 7 Copyright Qc 2015 by R J O'Connell&Associates,Inc N �h o �W oa 0.1C ..� 1f J. 's" Ne�cHeoe eusr�ss ,•m .,ss NIC V.,,NUE 7in-at AW 4 1 , 41. Ja NJ SS.'r '' $.551i n #33 D t �''�'' xJe �.Js. ♦ / a, wcu r 6 �` 'ieaim $4 suucsr caw+ - 8 Sq PAN icamW c�Eewar 5 Flec anew.�in'O S �! �a v'aMce'oF°1P�i Designed by: RWS t?,vx as' ,w� xrn' 'uitrrrrr gy '"t F Drawn by: BMS cauceA I _ a Checked by: JJS a d \ ewiaec rre7e�e-zet g'� g " / Scale: 1°=100' a- EX-1 b Date: 02/10/2015 Imo" e A=2.56 aC. / CN=91 O i w Prepared For: 7 EX-3 anon rote sraur s T I a ersraNc Fnamxrxr AR9 7�..ao:SQ. n , ,: ` eE \ A=4.56 aC. 4 BOYISTON PROFERJM fill 800 BOYLSTON STREET _ CjN=89 SUITE 1390 t SF BOSTON, MA 02199 a S c PHONE 617-262-4646 aaeio«n, Se r x 010 °0t' _°n'� S 8 ` RE> xc�warrxroxw cercxwar Prepared By: Aims � RJOrCONNELL o l dy &ASSOCIATES,INC. CIVIL ENGINEERS,SURVEYORS v I I \ LItJess Je.e S , S LAND PLANNERS 80 MO TVALE AVE F ONE81-279-0173HAM.MA 02180 Q PHONE 781-279-0180 w ®A--A I W I Q2=6.52 cfs o I Q =10.92 cfs t0 �1; � .y° Project Name: I I I Q25=14.26 cfs e # Ql,=21,11 cfs EX-2 A=0.81 ac. q� U WA a°°""`�`�""ar 480 SUITE 3 7, CN=94 o ARSENAL STREET y,q�� p �y 1\ A' p WATERTOWK MA d OA— \ \ Y Q2=2.27cTs � \ Qm=3.65cfs m 4, Q 25-4.69 cfs $� o \ Q,pp=6 84 cfs yry' Drawing Name: PFE- IGYGLt/f11/Ie4 \ / / WATERSHED PLAN 01 3 \ o s a o Drawing No.: ®A-C °K Q I \ Q2=10.83 cfs FIG. 5 1 I — �Qro=1�.69cfs y Q25=24.68cfs + 100 0 50 100 200 _ / £ —���oo=36.99 cfs m , rno na>wi O \ 1 c-' 'eta.sy. o' Project No.: 14074 GRAPHIC SCALE IN FEET p Copyright©2015 by R J O'Connell&Associates.Inc N / \ � V. g-_--"Pfferr 6 vC/VUj� / pax PR-1 s, A=1.58 ac. �iH IERTOWN CIffENIYAY Designed by: RWS Drawn by: BMS D e\ . • D • D / Checked by: JJS r Scale: 1"=100' Date: 02/10/2015 3 I = o u iLEVEL L I—96•o0f SF I / TOTAL 2=185,595 S.F.GFA PxOPOEA W..I 11 -11► I E Prepared ared For: C op BOYLSTON F'ROMT f8: E ( PR-3A 800 BOYLSTON STREET PR-2 PHONE 617-262-4646 0 A=4.65 ac. s--- _ A CN 81 C \ Bosro TE 'Iv9Mn o2ss / CN=90 '� R X { Exrsavc walExroxN cNEtrmIY Prepared By: ^/ R RJO'CONNELL - &ASSOCIATES,INC. / I ", • D L ' CIVIL ENGINEERS,SURVEYORS D—b BLAND PLANNERS j I D 80 MONTVALE AVE STONEHAM,MA 02180 LZ 781-2 � I �`�' W - PR-3B FAONE81-2 7 9-017 3 8 0 POA A D D A=0.51 ac. I W I I I Qz=0.00cfS s CN=54 / o I Q10=0.00cfs Rac••EowwulsNf yipry Project Name: /QZs=®.®o cfs „R� •AnONOF OMP 480 SUITE 3 x INVE RPEBO•EO P I I Qloo=6°81 cfs \ I D L I ARSENAL STREET ®A—B P JM15 PMS%i) 1 WATERTOWN,MA C I Q2=0.00cfs Qro=0.0(9 cfs 75 \ I Q2s=a00 cfs a D A m I Q"=o.00 cfs ..><1a•RwR m o x / \ rr -RAN TII1 ,Roxl•oF wR / Drawing Name: O \ I INVFM OF RR:�YID tO I \ I EBHOWy4.O EX-NO auMFIFAOE oErErmw \ AREA TANEx RmM.E..N RAN. POST DEVELOPMENT \ RE-V•PFY OR TO—FIT TO / � ERFr R.�R To•TART of o _ + aOF-Eucrlax Axo xonFr ENGINEER I 4 / O � / of azE ANo cox D NMFc; aM1 s ♦�ATEFISHED PLAN L7 _PR-4 /� \ A=0.61 ac. / • 01 / 1 CN=95 D i / /° / PR-5 i \ Ili „ Drawing No.: --o POAC ' A=0.21 as Q I \ CN=93 QZ=0.56 cfs \ r — —_— �Q,o=o.92cfs *� �R� FIG. 6 1I I Q25=1.18cfS 100 0 50 100 200 _ =4.54 cfs Project No.: GRAPHIC SCALE IN FEET 14074 p` Copyright(D2015 by R J.O'Connell&Associates.Inc III. HYDROLOGICAL CALCULATIONS PRE-DEVELOPMENT ANALYSIS EX-1 West Side of Site POA-A EX-2 18" Pipe Leaving West uthwest Side of Site Side of Site EX-3 ast Side of Site :POA-B 12" Pipe Leaving Southwest Side of Site [P:O A-C 18" Pipe Leaving South Side of Site Subcat Reach on Link Routing Diagram for Existing Conditions Prepared by{enter your company name here}, Printed 2/6/2015 HydroCAD®10.00 s/n 04881 ©2011 HydroCAD Software Solutions LLC HYDROGRAPHS - 2 YEAR STORM Existing Conditions Type 111 24-hr 2-Year Rainfall=3.20" Prepared by {enter your company name here) Printed 2/6/2015 HydroCAD® 10.00 s/n 04881 ©2011 HydroCAD Software Solutions LLC Paoe 2 Time span=0.00-24.00 hrs, dt=0.05 hrs, 481 points Runoff by SCS TR-20 method, UH=SCS Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method SubcatchmentEX-1:West Side of Site Runoff Area=111,500 sf 88.17% Impervious Runoff Depth>2.26" Tc=6.0 min CN=91 Runoff=6.52 cfs 0.481 of Subcatchment EX-2: Southwest Side of Runoff Area=35,407 sf 92.91% Impervious Runoff Depth>2.54" Tc=6.0 min CN=94 Runoff=2.27 cfs 0.172 of Subcatchment EX-3: East Side of Site Runoff Area=198,733 sf 85.22% Impervious Runoff Depth>2.08" Tc=6.0 min CN=89 Runoff=10.83 cfs 0.791 of Link POA-A: 18" Pipe Leaving West Side of Site Inflow=6.52 cfs 0.481 of Primary=6.52 cfs 0.481 of Link POA-B: 12" Pipe Leaving Southwest Side of Site Inflow=2.27 cfs 0.172 of Primary=2.27 cfs 0.172 of Link POA-C: 18" Pipe Leaving South Side of Site Inflow=10.83 cfs 0.791 of Primary=10.83 cfs 0.791 of Total Runoff Area = 7.935 ac Runoff Volume = 1.444 of Average Runoff Depth = 2.18" 13.04% Pervious = 1.035 ac 86.96% Impervious = 6.900 ac Existing Conditions Type 111 24-hr 2-Year Rainfall=3.20" Prepared by {enter your company name here) Printed 2/6/2015 HydroCADO 10.00 s/n 04881 ©2011 HydroCAD Software Solutions LLC Paqe 3 Summary for Subcatchment EX-1: West Side of Site Runoff = 6.52 cfs @ 12.09 hrs, Volume= 0.481 af, Depth> 2.26" Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs Type III 24-hr 2-Year Rainfall=3.20" Area (sf) CN Description 54,533 98 Roofs, HSG A 10,426 39 >75% Grass cover, Good, HSG A 2,760 45 Woods, Poor, HSG A 43,781 98 Paved parkinq, HSG A 111,500 91 Weighted Average 13,186 11.83% Pervious Area 98,314 88.17% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment EX-1: West Side of Site Hydrograph 7 ❑Runoff 6.52 cfs iy�e 11W24-h �-) fear Rainfall 3.2b 5�I Ru toff Ar&a#-4I11�5Q0 .sf 4�1 Rupoff Vollulnq=9.4§11 of �=6.0-min- 6N�91noff Delpth>2.26 3 O 3/ 1� 0 (....(... ... .. ... ... ... ...(,...(,.,. .... ..,.,,..., ,..,.. 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 Time (hours) Existing Conditions Type 111 24-hr 2-Year Rainfall=3.20" Prepared by {enter your company name here) Printed 2/6/2015 HydroCAD® 10.00 s/n 04881 ©2011 HydroCAD Software Solutions LLC Paqe 4 Summary for Subcatchment EX-2: Southwest Side of Site Runoff = 2.27 cfs @ 12.09 hrs, Volume= 0.172 af, Depth> 2.54" Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs Type III 24-hr 2-Year Rainfall=3.20" Area (sf) CN Description 2,510 39 >75% Grass cover, Good, HSG A 32,897 98 Paved parking, HSG A 35,407 94 Weighted Average 2,510 7.09% Pervious Area 32,897 92.91% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment EX-2: Southwest Side of Site Hydrograph ❑Runoff 2.27 cfs Type III 24-hr 2- 2-Year Rainfall=3.20" Runoff Area=35,407 sf Runoff Volume=0.172 of Runoff Depth>2.54" U. Tc=6.0 m i n 1- CN=94 o � ........,. 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 Time (hours) Existing Conditions Type 111 24-hr 2-Year Rainfall=3.20" Prepared by {enter your company name here) Printed 2/6/2015 HydroCADO 10.00 s/n 04881 ©2011 HydroCAD Software Solutions LLC Paqe 5 Summary for Subcatchment EX-3: East Side of Site Runoff = 10.83 cfs @ 12.09 hrs, Volume= 0.791 af, Depth> 2.08" Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs Type III 24-hr 2-Year Rainfall=3.20" Area (sf) CN Description 40,765 98 Roofs, HSG A 23,404 39 >75% Grass cover, Good, HSG A 5,977 45 Woods, Poor, HSG A 128,587 98 Paved parkinq, HSG A 198,733 89 Weighted Average 29,381 14.78% Pervious Area 169,352 85.22% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment EX-3: East Side of Site Hydrograph 12-� ❑Runoff 11 10.83 cfs 1 iy�e 'W1 24-h r ,9 1 �-Yealr kainfallLa-.2b" Runoff Area=198;733 �W 1- 1 4 1 7 f�u1o"o1ume=-q.7j';V1 rt rt 3 6�/ uoepth>F.08 l l 3� 4 —I4- 1 I4 4 1 1J I 2�Irt � l � J-- ' t Irtfil 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 Time (hours) Existing Conditions Type 111 24-hr 2-Year Rainfall=3.20" Prepared by {enter your company name here) Printed 2/6/2015 HydroCAD® 10.00 s/n 04881 ©2011 HydroCAD Software Solutions LLC Paqe 6 Summary for Link POA-A: 18" Pipe Leaving West Side of Site Inflow Area = 2.560 ac, 88.17% Impervious, Inflow Depth > 2.26" for 2-Year event Inflow = 6.52 cfs @ 12.09 hrs, Volume= 0.481 of Primary = 6.52 cfs @ 12.09 hrs, Volume= 0.481 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs Link POA-A: 18" Pipe Leaving West Side of Site Hydrograph / ❑Inflow 6.52 cfs ❑Primary M 5� I 3 - 0 LL 3� 1� 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 Time (hours) Existing Conditions Type 111 24-hr 2-Year Rainfall=3.20" Prepared by {enter your company name here) Printed 2/6/2015 HydroCAD® 10.00 s/n 04881 ©2011 HydroCAD Software Solutions LLC Paqe 7 Summary for Link POA-B: 12" Pipe Leaving Southwest Side of Site Inflow Area = 0.813 ac, 92.91% Impervious, Inflow Depth > 2.54" for 2-Year event Inflow = 2.27 cfs @ 12.09 hrs, Volume= 0.172 of Primary = 2.27 cfs @ 12.09 hrs, Volume= 0.172 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs Link POA-B: 12" Pipe Leaving Southwest Side of Site Hydrograph IIIII ❑Inflow 1'410�V l A�e6�0 I13 i 2.27 cfs ❑Primary 17 T IT FIB TI 2- N _ V 3 0 LL 1 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 Time (hours) Existing Conditions Type 111 24-hr 2-Year Rainfall=3.20" Prepared by {enter your company name here) Printed 2/6/2015 HydroCAD® 10.00 s/n 04881 ©2011 HydroCAD Software Solutions LLC Paqe 8 Summary for Link POA-C: 18" Pipe Leaving South Side of Site Inflow Area = 4.562 ac, 85.22% Impervious, Inflow Depth > 2.08" for 2-Year event Inflow = 10.83 cfs @ 12.09 hrs, Volume= 0.791 of Primary = 10.83 cfs @ 12.09 hrs, Volume= 0.791 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs Link POA-C: 18" Pipe Leaving South Side of Site Hydrograph 12 / ❑Inflow ❑Primary fl 11- Inflow Area=4.5 10.83 cfs 10 9 8 l l n 7i V --1T 3 6 0 LL 5 -T 4 T1-1 T ITT 3 2 1 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 Time (hours) HYDROGRAPHS - 10 YEAR STORM Existing Conditions Type/1/ 24-hr 10-Year Rainfall=4.90" Prepared by {enter your company name here) Printed 2/6/2015 HydroCAD® 10.00 s/n 04881 ©2011 HydroCAD Software Solutions LLC Paoe 9 Time span=0.00-24.00 hrs, dt=0.05 hrs, 481 points Runoff by SCS TR-20 method, UH=SCS Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method SubcatchmentEX-1:West Side of Site Runoff Area=111,500 sf 88.17% Impervious Runoff Depth>3.88" Tc=6.0 min CN=91 Runoff=10.92 cfs 0.828 of Subcatchment EX-2: Southwest Side of Runoff Area=35,407 sf 92.91% Impervious Runoff Depth>4.21" Tc=6.0 min CN=94 Runoff=3.65 cfs 0.285 of Subcatchment EX-3: East Side of Site Runoff Area=198,733 sf 85.22% Impervious Runoff Depth>3.67" Tc=6.0 min CN=89 Runoff=18.69 cfs 1.397 of Link POA-A: 18" Pipe Leaving West Side of Site Inflow=10.92 cfs 0.828 of Primary=10.92 cfs 0.828 of Link POA-B: 12" Pipe Leaving Southwest Side of Site Inflow=3.65 cfs 0.285 of Primary=3.65 cfs 0.285 of Link POA-C: 18" Pipe Leaving South Side of Site Inflow=18.69 cfs 1.397 of Primary=18.69 cfs 1.397 of Total Runoff Area = 7.935 ac Runoff Volume = 2.510 of Average Runoff Depth = 3.80" 13.04% Pervious = 1.035 ac 86.96% Impervious = 6.900 ac Existing Conditions Type 111 24-hr 10-Year Rainfall=4.90" Prepared by {enter your company name here) Printed 2/6/2015 HydroCADO 10.00 s/n 04881 ©2011 HydroCAD Software Solutions LLC Paqe 10 Summary for Subcatchment EX-1: West Side of Site Runoff = 10.92 cfs @ 12.09 hrs, Volume= 0.828 af, Depth> 3.88" Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs Type III 24-hr 10-Year Rainfall=4.90" Area (sf) CN Description 54,533 98 Roofs, HSG A 10,426 39 >75% Grass cover, Good, HSG A 2,760 45 Woods, Poor, HSG A 43,781 98 Paved parkinq, HSG A 111,500 91 Weighted Average 13,186 11.83% Pervious Area 98,314 88.17% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment EX-1: West Side of Site Hydrograph � � ❑Runoff I I � 10.92 cfs 11 Type I1L24�,� 19�I 41-0-�arl Rai nfaliW4- .1D'I'—I 8 I Rut off-Area-411 "00 �,f -4 N ,�I -Rulio"ol ulm�`4•$?81 af 1 1 t 1 1 t l �E U�O" t�>�.18 - — — — — — — — LL .V 41 NL911 I_I l 3�z1 4 1— 4- 1I 4 11 4 11 4 I- 2�1 J-- - Irt fil o �..�,.�..�..�.,�.,,� ,„�i,,,�,,,,��,,,,• ,,,, ,,,, 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 Time (hours) Existing Conditions Type 111 24-hr 10-Year Rainfall=4.90" Prepared by {enter your company name here) Printed 2/6/2015 HydroCADO 10.00 s/n 04881 ©2011 HydroCAD Software Solutions LLC Paqe 11 Summary for Subcatchment EX-2: Southwest Side of Site Runoff = 3.65 cfs @ 12.09 hrs, Volume= 0.285 af, Depth> 4.21" Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs Type III 24-hr 10-Year Rainfall=4.90" Area (sf) CN Description 2,510 39 >75% Grass cover, Good, HSG A 32,897 98 Paved parking, HSG A 35,407 94 Weighted Average 2,510 7.09% Pervious Area 32,897 92.91% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment EX-2: Southwest Side of Site Hydrograph 4�� � � � � � � � � � ❑Runoff 3.65 cfs - l y�e III 241-h� 104ear Rainfa1IW— .§0�' 3�1 Runoff Area=35,407 sf Runoff Vollume=9.2851 of 2�/ wolf Delyt~ 141" 0 �Ic=6.0 min 6N�94 1 0 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 Time (hours) Existing Conditions Type 111 24-hr 10-Year Rainfall=4.90" Prepared by {enter your company name here) Printed 2/6/2015 HydroCADO 10.00 s/n 04881 ©2011 HydroCAD Software Solutions LLC Paqe 12 Summary for Subcatchment EX-3: East Side of Site Runoff = 18.69 cfs @ 12.09 hrs, Volume= 1.397 af, Depth> 3.67" Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs Type III 24-hr 10-Year Rainfall=4.90" Area (sf) CN Description 40,765 98 Roofs, HSG A 23,404 39 >75% Grass cover, Good, HSG A 5,977 45 Woods, Poor, HSG A 128,587 98 Paved parkinq, HSG A 198,733 89 Weighted Average 29,381 14.78% Pervious Area 169,352 85.22% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment EX-3: East Side of Site Hydrograph f L 1 1 — 1 -4 L- Runoff 20—/ 18.69 cfs 1 - 1 1 I 1 � 19L/1 iY� IIH'2 - 16-1 — —ear+Rai r�— 1=4.�O'I'- I— 4 - 1 -1 - I— I - - 15 14� u6or#a �98733 is LZ :!E 11 u 0101 '° — — - I - I — - I I - I I — LL 9_ c �i.�min 8L'/ � Z — - E - - 1 ::1 - I -1 I - 1 ::1 Z 7- 5- 14 3 1= 0" (.... '.. .... ........ ... ... ....(,.,,(,.,. 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 Time (hours) Existing Conditions Type 111 24-hr 10-Year Rainfall=4.90" Prepared by {enter your company name here) Printed 2/6/2015 HydroCADO 10.00 s/n 04881 ©2011 HydroCAD Software Solutions LLC Paqe 13 Summary for Link POA-A: 18" Pipe Leaving West Side of Site Inflow Area = 2.560 ac, 88.17% Impervious, Inflow Depth > 3.88" for 10-Year event Inflow = 10.92 cfs @ 12.09 hrs, Volume= 0.828 of Primary = 10.92 cfs @ 12.09 hrs, Volume= 0.828 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs Link POA-A: 18" Pipe Leaving West Side of Site Hydrograph �� I I - � I -f I fi Inflow 12- � 10.92 ❑Primary cfs 10� � � 0 " 5� 3� 2� 1� ................. 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 Time (hours) Existing Conditions Type/1/ 24-hr 10-Year Rainfall=4.90" Prepared by {enter your company name here) Printed 2/6/2015 HydroCAD® 10.00 s/n 04881 ©2011 HydroCAD Software Solutions LLC Paqe 14 Summary for Link POA-B: 12" Pipe Leaving Southwest Side of Site Inflow Area = 0.813 ac, 92.91% Impervious, Inflow Depth > 4.21" for 10-Year event Inflow = 3.65 cfs @ 12.09 hrs, Volume= 0.285 of Primary = 3.65 cfs @ 12.09 hrs, Volume= 0.285 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs Link POA-B: 12" Pipe Leaving Southwest Side of Site Hydrograph / ❑Inflow 4 ❑Primary Inflow Area=0.81 3.65 cfs 3- V 3 2 0 LL 1 0 ... �. �. 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 Time (hours) Existing Conditions Type/1/ 24-hr 10-Year Rainfall=4.90" Prepared by {enter your company name here) Printed 2/6/2015 HydroCAD® 10.00 s/n 04881 ©2011 HydroCAD Software Solutions LLC Paqe 15 Summary for Link POA-C: 18" Pipe Leaving South Side of Site Inflow Area = 4.562 ac, 85.22% Impervious, Inflow Depth > 3.67" for 10-Year event Inflow = 18.69 cfs @ 12.09 hrs, Volume= 1.397 of Primary = 18.69 cfs @ 12.09 hrs, Volume= 1.397 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs Link POA-C: 18" Pipe Leaving South Side of Site Hydrograph r ❑Inflow 20= 18.69 cfs ❑Primary 19 laloiv �-e�a-4.5 18 Ex — 17- 15- � 14 X _ 11� � 0 10- — - 9 — 8. - 6I rt rt fi I- 5- 4� 1 1 1 1— I -' 2- 1 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 Time (hours) HYDROGRAPHS - 25 YEAR STORM Existing Conditions Type/1/ 24-hr 25-Year Rainfall=6.20" Prepared by {enter your company name here) Printed 2/6/2015 HydroCAD® 10.00 s/n 04881 ©2011 HydroCAD Software Solutions LLC Paoe 16 Time span=0.00-24.00 hrs, dt=0.05 hrs, 481 points Runoff by SCS TR-20 method, UH=SCS Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method SubcatchmentEX-1:West Side of Site Runoff Area=111,500 sf 88.17% Impervious Runoff Depth>5.15" Tc=6.0 min CN=91 Runoff=14.26 cfs 1.098 of Subcatchment EX-2: Southwest Side of Runoff Area=35,407 sf 92.91% Impervious Runoff Depth>5.49" Tc=6.0 min CN=94 Runoff=4.69 cfs 0.372 of Subcatchment EX-3: East Side of Site Runoff Area=198,733 sf 85.22% Impervious Runoff Depth>4.93" Tc=6.0 min CN=89 Runoff=24.68 cfs 1.873 of Link POA-A: 18" Pipe Leaving West Side of Site Inflow=14.26 cfs 1.098 of Primary=14.26 cfs 1.098 of Link POA-B: 12" Pipe Leaving Southwest Side of Site Inflow=4.69 cfs 0.372 of Primary=4.69 cfs 0.372 of Link POA-C: 18" Pipe Leaving South Side of Site Inflow=24.68 cfs 1.873 of Primary=24.68 cfs 1.873 of Total Runoff Area = 7.935 ac Runoff Volume = 3.343 of Average Runoff Depth = 5.06" 13.04% Pervious = 1.035 ac 86.96% Impervious = 6.900 ac Existing Conditions Type 111 24-hr 25-Year Rainfall=6.20" Prepared by {enter your company name here) Printed 2/6/2015 HydroCADO 10.00 s/n 04881 ©2011 HydroCAD Software Solutions LLC Paqe 17 Summary for Subcatchment EX-1: West Side of Site Runoff = 14.26 cfs @ 12.09 hrs, Volume= 1.098 af, Depth> 5.15" Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs Type III 24-hr 25-Year Rainfall=6.20" Area (sf) CN Description 54,533 98 Roofs, HSG A 10,426 39 >75% Grass cover, Good, HSG A 2,760 45 Woods, Poor, HSG A 43,781 98 Paved parkinq, HSG A 111,500 91 Weighted Average 13,186 11.83% Pervious Area 98,314 88.17% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment EX-1: West Side of Site Hydrograph / — — ❑Runoff 11.211 fy iu24�-h� 13_ �54 a�R�jnfail-4.�O"-] 1 -1 L 1 - 12 11-/1 Ru6o rOa#-411IMO �sfI 1 -T T- 1 - 10 u o op .0F8 3 $' Runoff,t�»515 I— —I 7-�/ fiC=6.0 m i n 3=L LI -1 - I L I_ I o- ;.,�..�,.�..�..�.,�„� 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 Time (hours) Existing Conditions Type 111 24-hr 25-Year Rainfall=6.20" Prepared by {enter your company name here) Printed 2/6/2015 HydroCADO 10.00 s/n 04881 ©2011 HydroCAD Software Solutions LLC Paqe 18 Summary for Subcatchment EX-2: Southwest Side of Site Runoff = 4.69 cfs @ 12.09 hrs, Volume= 0.372 af, Depth> 5.49" Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs Type III 24-hr 25-Year Rainfall=6.20" Area (sf) CN Description 2,510 39 >75% Grass cover, Good, HSG A 32,897 98 Paved parking, HSG A 35,407 94 Weighted Average 2,510 7.09% Pervious Area 32,897 92.91% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment EX-2: Southwest Side of Site Hydrograph I T 5 ❑Runoff 4.69 cfs l y�e III 241-h� 4�1 2�5*ear Rainfa111=�6.$&--4 Runoff Area7-35,407 slf N 3 1 Runoff VolIuT��•317210 unoff Delpt�>l5'19 2 Tc=6.0 min _ 2�-z �N�947 T 7 T - IIIIIIII 0 �..�..�..�..�../. %. 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 Time (hours) Existing Conditions Type 111 24-hr 25-Year Rainfall=6.20" Prepared by {enter your company name here) Printed 2/6/2015 HydroCADO 10.00 s/n 04881 ©2011 HydroCAD Software Solutions LLC Paqe 19 Summary for Subcatchment EX-3: East Side of Site Runoff = 24.68 cfs @ 12.09 hrs, Volume= 1.873 af, Depth> 4.93" Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs Type III 24-hr 25-Year Rainfall=6.20" Area (sf) CN Description 40,765 98 Roofs, HSG A 23,404 39 >75% Grass cover, Good, HSG A 5,977 45 Woods, Poor, HSG A 128,587 98 Paved parkinq, HSG A 198,733 89 Weighted Average 29,381 14.78% Pervious Area 169,352 85.22% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment EX-3: East Side of Site Hydrograph �� I �Runoff 26--�/I 24168 cfs 24� l y e 111 24-h - -+ 22'/1 2i5*� a7Riir —f jI�6.:0'I' T — — — — — — — — 20�I #ut-off-Arb&dM733 Ise 1 1 -4 �- 1 1 1 - 18 n 16�I flu o /ol u rye= .83 rt rt fi L 1 -] -1 L 1 -1 - — 1 - LL 12�,/ �Ic=b.qmin 1031/ GN�89� 4� 2-� I 0 (.... .. .. .. ..(.... ... ....(,.,.(:.../.,.., ,.,, .,,, 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 Time (hours) Existing Conditions Type/1/ 24-hr 25-Year Rainfall=6.20" Prepared by {enter your company name here) Printed 2/6/2015 HydroCAD® 10.00 s/n 04881 ©2011 HydroCAD Software Solutions LLC Paqe 20 Summary for Link POA-A: 18" Pipe Leaving West Side of Site Inflow Area = 2.560 ac, 88.17% Impervious, Inflow Depth > 5.15" for 25-Year event Inflow = 14.26 cfs @ 12.09 hrs, Volume= 1.098 of Primary = 14.26 cfs @ 12.09 hrs, Volume= 1.098 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs Link POA-A: 18" Pipe Leaving West Side of Site Hydrograph ❑Inflow 14.26 cfs 12 Primary � � � � fi 14 Inflow Area=2.5 �. 10 5� � 1 1 1 I I j F I - 1 I I I 1-1 -1 I I I 4� — 3-�-/ -^ 1 t I— I tt-- I -t fi I t 2 1=� 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 Time (hours) Existing Conditions Type/1/ 24-hr 25-Year Rainfall=6.20" Prepared by {enter your company name here) Printed 2/6/2015 HydroCAD® 10.00 s/n 04881 ©2011 HydroCAD Software Solutions LLC Paqe 21 Summary for Link POA-B: 12" Pipe Leaving Southwest Side of Site Inflow Area = 0.813 ac, 92.91% Impervious, Inflow Depth > 5.49" for 25-Year event Inflow = 4.69 cfs @ 12.09 hrs, Volume= 0.372 of Primary = 4.69 cfs @ 12.09 hrs, Volume= 0.372 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs Link POA-B: 12" Pipe Leaving Southwest Side of Site Hydrograph -1 L I —1 ❑Inflow 5- ❑Primary - Inflow Area=0.81 4.69 cfs I � I 4 n 3 I IIIIIIII 3 0 " 2 1 o �:.., r..r..�..�:..�...�:... ... .... .... 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 Time (hours) Existing Conditions Type/1/ 24-hr 25-Year Rainfall=6.20" Prepared by {enter your company name here) Printed 2/6/2015 HydroCAD® 10.00 s/n 04881 ©2011 HydroCAD Software Solutions LLC Paqe 22 Summary for Link POA-C: 18" Pipe Leaving South Side of Site Inflow Area = 4.562 ac, 85.22% Impervious, Inflow Depth > 4.93" for 25-Year event Inflow = 24.68 cfs @ 12.09 hrs, Volume= 1.873 of Primary = 24.68 cfs @ 12.09 hrs, Volume= 1.873 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs Link POA-C: 18" Pipe Leaving South Side of Site Hydrograph / ❑Inflow ❑Primary fl 26- Inflow Area=4.5 24.68 cfs 24 22- 20 18- N 16 u 14- 3 0 FL 12 10 8 4- 1-1 1I 6 4- 2- 0 .................�..�..r..�..,....,.... . 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 Time (hours) HYDROGRAPHS - 100 YEAR STORM Existing Conditions Type/1/ 24-hr 100-Year Rainfall=8.90" Prepared by {enter your company name here) Printed 2/6/2015 HydroCAD® 10.00 s/n 04881 ©2011 HydroCAD Software Solutions LLC Paoe 23 Time span=0.00-24.00 hrs, dt=0.05 hrs, 481 points Runoff by SCS TR-20 method, UH=SCS Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method SubcatchmentEX-1:West Side of Site Runoff Area=111,500 sf 88.17% Impervious Runoff Depth>7.81" Tc=6.0 min CN=91 Runoff=21.11 cfs 1.666 of Subcatchment EX-2: Southwest Side of Runoff Area=35,407 sf 92.91% Impervious Runoff Depth>8.17" Tc=6.0 min CN=94 Runoff=6.84 cfs 0.554 of Subcatchment EX-3: East Side of Site Runoff Area=198,733 sf 85.22% Impervious Runoff Depth>7.57" Tc=6.0 min CN=89 Runoff=36.99 cfs 2.877 of Link POA-A: 18" Pipe Leaving West Side of Site Inflow=21.11 cfs 1.666 of Primary=21.11 cfs 1.666 of Link POA-B: 12" Pipe Leaving Southwest Side of Site Inflow=6.84 cfs 0.554 of Primary=6.84 cfs 0.554 of Link POA-C: 18" Pipe Leaving South Side of Site Inflow=36.99 cfs 2.877 of Primary=36.99 cfs 2.877 of Total Runoff Area = 7.935 ac Runoff Volume = 5.096 of Average Runoff Depth = 7.71" 13.04% Pervious = 1.035 ac 86.96% Impervious = 6.900 ac Existing Conditions Type 111 24-hr 100-Year Rainfall=8.90" Prepared by {enter your company name here) Printed 2/6/2015 HydroCADO 10.00 s/n 04881 ©2011 HydroCAD Software Solutions LLC Paqe 24 Summary for Subcatchment EX-1: West Side of Site Runoff = 21.11 cfs @ 12.09 hrs, Volume= 1.666 af, Depth> 7.81" Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs Type III 24-hr 100-Year Rainfall=8.90" Area (sf) CN Description 54,533 98 Roofs, HSG A 10,426 39 >75% Grass cover, Good, HSG A 2,760 45 Woods, Poor, HSG A 43,781 98 Paved parkinq, HSG A 111,500 91 Weighted Average 13,186 11.83% Pervious Area 98,314 88.17% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment EX-1: West Side of Site Hydrograph 23 zi- ■Runoff 22� 21.11 cfs ,I � — I —2� —I 19e1 40"- ear Hai ffa[t= 9b- 1 1 -1 + I 1 4 18- 17 16 E tau ftoff—Arta#4 f1 t500 !sf-1 t 1 1 t I --- t 313 -�/12 z11' 1 u�o"epth>7.11 LL19�1 I - :IEI 7 1 1 � � I I I I � � $� -N�91 � II � � I � III 6- LZ — — 4LZ1 r _ L1 I 3- � 1 1 0' (:... .... .... .... ....�..(....�... ....(;.,,(;,,. ...,, .,.,,...,.,..,.. 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 Time (hours) Existing Conditions Type 111 24-hr 100-Year Rainfall=8.90" Prepared by {enter your company name here) Printed 2/6/2015 HydroCADO 10.00 s/n 04881 ©2011 HydroCAD Software Solutions LLC Paqe 25 Summary for Subcatchment EX-2: Southwest Side of Site Runoff = 6.84 cfs @ 12.09 hrs, Volume= 0.554 af, Depth> 8.17" Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs Type III 24-hr 100-Year Rainfall=8.90" Area (sf) CN Description 2,510 39 >75% Grass cover, Good, HSG A 32,897 98 Paved parking, HSG A 35,407 94 Weighted Average 2,510 7.09% Pervious Area 32,897 92.91% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment EX-2: Southwest Side of Site Hydrograph A ❑Runoff 6.84 cfs - 7�I �ype 11111241-h 6�I rt00 Year kainfalrt 8-.9b" 5�1 Runoff Area=35,407 sf Runoff Vollume=9.5541 aid 4�--/ unofMelpt�>I .17 3� 6NL94 1 0 .4..�..�.,.,'.,,, 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 Time (hours) Existing Conditions Type 111 24-hr 100-Year Rainfall=8.90" Prepared by {enter your company name here) Printed 2/6/2015 HydroCADO 10.00 s/n 04881 ©2011 HydroCAD Software Solutions LLC Paqe 26 Summary for Subcatchment EX-3: East Side of Site Runoff = 36.99 cfs @ 12.09 hrs, Volume= 2.877 af, Depth> 7.57" Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs Type III 24-hr 100-Year Rainfall=8.90" Area (sf) CN Description 40,765 98 Roofs, HSG A 23,404 39 >75% Grass cover, Good, HSG A 5,977 45 Woods, Poor, HSG A 128,587 98 Paved parkinq, HSG A 198,733 89 Weighted Average 29,381 14.78% Pervious Area 169,352 85.22% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment EX-3: East Side of Site Hydrograph 4 1 4 ■Runoff 38-:-/ 36.99 cfs 1 4 36� y 1IL24---h 34 32=-I �I�O�e-ar kai-n6li=". b" I 30 28 1 Ruhoff-Ari�a#49M33 !sf-1 1- 1 -f t 1 1 t I I t 24�11 uool� •81 1 rt l rt l fi 320� u Tt�> FLIP I � ZI 1 I I I � Z il:0 18 / Ci mil. _n J� 16� �N�--8�-j L -i L1 1- 1 -LL1 1 1 1 -[ L 14- - — — — — — — — — — — — — — — — — 10=/ - - — 8� 6- 4 2= 0: 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 Time (hours) Existing Conditions Type 111 24-hr 100-Year Rainfall=8.90" Prepared by {enter your company name here) Printed 2/6/2015 HydroCADO 10.00 s/n 04881 ©2011 HydroCAD Software Solutions LLC Paqe 27 Summary for Link POA-A: 18" Pipe Leaving West Side of Site Inflow Area = 2.560 ac, 88.17% Impervious, Inflow Depth > 7.81" for 100-Year event Inflow = 21.11 cfs @ 12.09 hrs, Volume= 1.666 of Primary = 21.11 cfs @ 12.09 hrs, Volume= 1.666 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs Link POA-A: 18" Pipe Leaving West Side of Site Hydrograph — — — — — — I C Inflow 22 I4I . 21.11 cfs _ Primary ll 20 19 18 17 16 — — — 15 13 12 " '°'' l fi l 9-/-/ � 6= 5�4 � - - - - � fi fiI rt rt � � fi � 2: 1� 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 Time (hours) Existing Conditions Type/1/ 24-hr 100-Year Rainfall=8.90" Prepared by {enter your company name here) Printed 2/6/2015 HydroCAD® 10.00 s/n 04881 ©2011 HydroCAD Software Solutions LLC Paqe 28 Summary for Link POA-B: 12" Pipe Leaving Southwest Side of Site Inflow Area = 0.813 ac, 92.91% Impervious, Inflow Depth > 8.17" for 100-Year event Inflow = 6.84 cfs @ 12.09 hrs, Volume= 0.554 of Primary = 6.84 cfs @ 12.09 hrs, Volume= 0.554 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs Link POA-B: 12" Pipe Leaving Southwest Side of Site Hydrograph /I I I I I I ❑Inflow 11 7- 111410�V'A�e6�0.8'! 6.84 cfs ❑Primary 6- I I 5 N 4 3 0 " 3-1 1� I o �'...�:..�... ..�..�..�..�...�:...�... .... ... 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 Time (hours) Existing Conditions Type/1/ 24-hr 100-Year Rainfall=8.90" Prepared by {enter your company name here) Printed 2/6/2015 HydroCAD® 10.00 s/n 04881 ©2011 HydroCAD Software Solutions LLC Paqe 29 Summary for Link POA-C: 18" Pipe Leaving South Side of Site Inflow Area = 4.562 ac, 85.22% Impervious, Inflow Depth > 7.57" for 100-Year event Inflow = 36.99 cfs @ 12.09 hrs, Volume= 2.877 of Primary = 36.99 cfs @ 12.09 hrs, Volume= 2.877 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs Link POA-C: 18" Pipe Leaving South Side of Site Hydrograph / 4 _ ❑Inflow 40� _ 36.99 cfs I❑Primary 38 Iia#Iow Araa-4.5 + 32- _ 30j I Z CI I � 1 � 1 ED I E 1 Z E: 1 :1 Z 28- _ 24_/ 22 II I I 3 20 18 16� � I fiI ItI I � � I � fi - — 14 � rt — ICI -T r- I -I -r- 12- 10 4 2 0- ..............�..�..r..�..,....,.... .........I..... ...,....,....,.. . 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 Time (hours) POST-DEVELOPMENT ANALYSIS SED C PR-4 Sedimen Forebay E Site Parking V PR-2 SWALE C PR-3B O O S Site a,d Roof Wa r Quality Swale E Site PR-4 PR-1 v POA-A C SSI-2 SW Site NE Site 18"Pipe Leaving West Subsurface Infiltration Side of Site Basin 2-South V V PR-5 ssl-3 ssl-1 O POA-B S Site Not Det ed Subsurfaci Infiltration Sub rface Infiltration Basin 3--outhwest Basin 1-East 12"Pipe Leaving Southwest Side of Site POA-C 18"Pipe Leaving South Side of Site SubCat Reach on Link Routing Diagram for Proposed Conditions_Resub.2015-03-27 Prepared by{enter your company name here}, Printed 3/26/2015 HydroCAD®10.00 s/n 04881 ©2011 HydroCAD Software Solutions LLC HYDROGRAPHS - 2 YEAR STORM Proposed Conditions_Resub. 2015-03-27 Type 111 24-hr 2-Year Rainfall=3.20" Prepared by {enter your company name here) Printed 3/26/2015 HydroCAD® 10.00 s/n 04881 ©2011 HydroCAD Software Solutions LLC Paoe 2 Time span=0.00-24.00 hrs, dt=0.05 hrs, 481 points Runoff by SCS TR-20 method, UH=SCS Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method Link POA-A: 18" Pipe Leaving West Side of Site Inflow=0.00 cfs 0.000 of Primary=0.00 cfs 0.000 of Link POA-B: 12" Pipe Leaving Southwest Side of Site Primary=0.00 cfs 0.000 of Link POA-C: 18" Pipe Leaving South Side of Site Inflow=0.56 cfs 0.042 of Primary=0.56 cfs 0.042 of SubcatchmentPR-1: NE Site Runoff Area=68,842 sf 82.97% Impervious Runoff Depth>2.00" Tc=6.0 min CN=88 Runoff=3.61 cfs 0.263 of SubcatchmentPR-2: S Site and Roof Runoff Area=202,664 sf 86.29% Impervious Runoff Depth>2.17" Tc=6.0 min CN=90 Runoff=11.45 cfs 0.840 of SubcatchmentPR-3A: E Site Parking Runoff Area=23,125 sf 71.77% Impervious Runoff Depth>1.47" Tc=6.0 min CN=81 Runoff=0.89 cfs 0.065 of SubcatchmentPR-3B: E Site Runoff Area=22,103 sf 25.70% Impervious Runoff Depth>0.22" Tc=6.0 min CN=54 Runoff=0.04 cfs 0.009 of SubcatchmentPR-4: SW Site Runoff Area=26,493 sf 94.30% Impervious Runoff Depth>2.64" Tc=6.0 min CN=95 Runoff=1.74 cfs 0.134 of SubcatchmentPR-5: S Site Not Detained Runoff Area=9,032 sf 91.74% Impervious Runoff Depth>2.44" Tc=6.0 min CN=93 Runoff=0.56 cfs 0.042 of Pond SED: Sediment Forebay Peak Elev=35.91' Storage=1,029 cf Inflow=0.89 cfs 0.065 of Discarded=0.15 cfs 0.065 of Primary=0.00 cfs 0.000 of Outflow=0.15 cfs 0.065 of Pond SSI-1: Subsurface Infiltration Basin Peak Elev=29.71' Storage=0.110 of Inflow=3.61 cfs 0.263 of Discarded=0.29 cfs 0.262 of Primary=0.00 cfs 0.000 of Outflow=0.29 cfs 0.262 of Pond SSI-2: Subsurface Infiltration Basin Peak EIev=31.10' Storage=0.298 of Inf1ow=11.45 cfs 0.840 of Discarded=1.30 cfs 0.839 of Primary=0.00 cfs 0.000 of Outflow=1.30 cfs 0.839 of Pond SSI-3: Subsurface Infiltration Basin Peak EIev=30.76' Storage=1,697 cf Inflow=1.74 cfs 0.134 of Discarded=0.28 cfs 0.134 of Primary=0.00 cfs 0.000 of Outflow=0.28 cfs 0.134 of Pond SWALE:Water Quality Swale Peak EIev=34.07' Storage=8 cf Inflow=0.04 cfs 0.009 of Discarded=0.04 cfs 0.009 of Primary=0.00 cfs 0.000 of Outflow=0.04 cfs 0.009 of Total Runoff Area = 8.087 ac Runoff Volume = 1.353 of Average Runoff Depth = 2.01" 18.37% Pervious = 1.486 ac 81.63% Impervious = 6.601 ac Proposed Conditions_Resub. 2015-03-27 Type 111 24-hr 2-Year Rainfall=3.20" Prepared by {enter your company name here) Printed 3/26/2015 HydroCAD® 10.00 s/n 04881 ©2011 HydroCAD Software Solutions LLC Paqe 3 Summary for Link POA-A: 18" Pipe Leaving West Side of Site Inflow Area = 5.691 ac, 79.53% Impervious, Inflow Depth = 0.00" for 2-Year event Inflow = 0.00 cfs @ 0.00 hrs, Volume= 0.000 of Primary = 0.00 cfs @ 0.00 hrs, Volume= 0.000 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs Link POA-A: 18" Pipe Leaving West Side of Site Hydrograph / ❑Inflow 1 ❑Primary Inflow Area=5.691 ac N V 3 0 0.00 cfs 0 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 Time (hours) Proposed Conditions_Resub. 2015-03-27 Type 111 24-hr 2-Year Rainfall=3.20" Prepared by {enter your company name here) Printed 3/26/2015 HydroCAD® 10.00 s/n 04881 ©2011 HydroCAD Software Solutions LLC Paqe 4 Summary for Link POA-B: 12" Pipe Leaving Southwest Side of Site [43] Hint: Has no inflow (Outflow=Zero) Primary = 0.00 cfs @ 0.00 hrs, Volume= 0.000 of Primary outflow = Inflow, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs Link POA-B: 12" Pipe Leaving Southwest Side of Site Hydrograph 1 ❑Primary w - i 3 0 LL 0.00 cfs 0 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 Time (hours) Proposed Conditions_Resub. 2015-03-27 Type 111 24-hr 2-Year Rainfall=3.20" Prepared by {enter your company name here) Printed 3/26/2015 HydroCAD® 10.00 s/n 04881 ©2011 HydroCAD Software Solutions LLC Paqe 5 Summary for Link POA-C: 18" Pipe Leaving South Side of Site Inflow Area = 2.396 ac, 86.61% Impervious, Inflow Depth > 0.21" for 2-Year event Inflow = 0.56 cfs @ 12.09 hrs, Volume= 0.042 of Primary = 0.56 cfs @ 12.09 hrs, Volume= 0.042 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs Link POA-C: 18" Pipe Leaving South Side of Site Hydrograph ❑Inflow ❑Primary 06� Inflow Area 2.3% 0.56 cfs 0.5�'/ 0.45� 0.4-�'/ - 0.35� u _ c 0.3�-/LL 0.25�-/ 0.2�'z 0.15-�/ 0.1� 0.05--�Z 0 .,,�. 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 Time (hours) Proposed Conditions_Resub. 2015-03-27 Type 111 24-hr 2-Year Rainfall=3.20" Prepared by {enter your company name here) Printed 3/26/2015 HydroCADO 10.00 s/n 04881 ©2011 HydroCAD Software Solutions LLC Paqe 6 Summary for Subcatchment PR-1: NE Site Runoff = 3.61 cfs @ 12.09 hrs, Volume= 0.263 af, Depth> 2.00" Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs Type III 24-hr 2-Year Rainfall=3.20" Area (sf) CN Description 11,721 39 >75% Grass cover, Good, HSG A 57,121 98 Paved parkin❑, HSG A 68,842 88 Weighted Average 11,721 17.03% Pervious Area 57,121 82.97% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment PR-1: NE Site Hydrograph ❑Runoff 3.61 cfs l y�e III 241-h� �-) fear RainfA=3-.20" 3 I Runoff Area�=68,842 sf Runoff Vollume=e.263 of 3 2� Z off Dept~ >F-�O=6.0 min 6NL88 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 Time (hours) Proposed Conditions_Resub. 2015-03-27 Type 111 24-hr 2-Year Rainfall=3.20" Prepared by {enter your company name here) Printed 3/26/2015 HydroCADO 10.00 s/n 04881 ©2011 HydroCAD Software Solutions LLC Paqe 7 Summary for Subcatchment PR-2: S Site and Roof Runoff = 11.45 cfs @ 12.09 hrs, Volume= 0.840 af, Depth> 2.17" Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs Type III 24-hr 2-Year Rainfall=3.20" Area (sf) CN Description 96,885 98 Roofs, HSG A 27,790 39 >75% Grass cover, Good, HSG A 77,989 98 Paved parkinq, HSG A 202,664 90 Weighted Average 27,790 13.71% Pervious Area 174,874 86.29% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment PR-2: S Site and Roof Hydrograph ./I I I I I ❑Runoff 12� � 11.45 cfs 11�I Ype I11�24�h� 10 '/12i-Y6-alr- afnf611�=-3t.26-'-' 9�-/1 Ruhoff Arha#2OZ664 Isf 8 I F�UITOff Yo u- -q•819 0 I -t L 0 6�1 c - in 5� L W9 4�1 -iLI -1L1I _' 3� 0- .... .... .. .. .. .. ..�...�:...�:...�....�...., 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 Time (hours) Proposed Conditions_Resub. 2015-03-27 Type 111 24-hr 2-Year Rainfall=3.20" Prepared by {enter your company name here) Printed 3/26/2015 HydroCADO 10.00 s/n 04881 ©2011 HydroCAD Software Solutions LLC Paqe 8 Summary for Subcatchment PR-3A: E Site Parking Runoff = 0.89 cfs @ 12.10 hrs, Volume= 0.065 af, Depth> 1.47" Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs Type III 24-hr 2-Year Rainfall=3.20" Area (sf) CN Description 6,529 39 >75% Grass cover, Good, HSG A 16,596 98 Paved parking, HSG A 23,125 81 Weighted Average 6,529 28.23% Pervious Area 16,596 71.77% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment PR-3A: E Site Parking Hydrograph L I L L L L A L I Runoff 0.95- — 0.89 cfs 0.9-/ I�f1�2�=hl�l � L 1 I I L -1 L I 0.85 - 0.75 0.7-' RU off-ArOnO-2I3,M-O - I -] 1-1 4 1 0.65-f`/ 0.6--/ �u�ol��u���•q�l a� - � � � � --4 4-- o 0-5 5 1 wu rolff�e�pt�»I1 71- - 4- 1-1 4 � I -t � u_ 0.45- �i.= .G—M[ 0.4 N�81� L L 1-1 4 0.35= 0.3�'/1 4 L + 4 1 --1 L 1-1 4 0.25�Z 05 0 -L'/1I 0.1 f�1 0.05— o 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 Time (hours) Proposed Conditions_Resub. 2015-03-27 Type 111 24-hr 2-Year Rainfall=3.20" Prepared by {enter your company name here) Printed 3/26/2015 HydroCADO 10.00 s/n 04881 ©2011 HydroCAD Software Solutions LLC Paqe 9 Summary for Subcatchment PR-3B: E Site Runoff = 0.04 cfs @ 12.36 hrs, Volume= 0.009 af, Depth> 0.22" Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs Type III 24-hr 2-Year Rainfall=3.20" Area (sf) CN Description 16,423 39 >75% Grass cover, Good, HSG A 5,680 98 Paved parking, HSG A 22,103 54 Weighted Average 16,423 74.30% Pervious Area 5,680 25.70% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment PR-3B: E Site Hydrograph 0.046 ■Runoff 0.044- 1 0.04 cfs 0.042� Tye �W2 r — 0.04 0.038� Ye�alraa�+ = Z°" 0.036 — 0.034032' -Ru iid'ff-Ar*a=22,403-V+ 1 4 �- I --� 4- 1-1 + 1 N 0 028�' Q 1 -1 L I --J -L I I -L L I 0.026 fi�l�_ flu °f�Ie ° 2I 1 1 1 1 1 3 0.024� 0 0.022' =6.°-min — — '� .018 V N-L�� 0.016- - 0.014� � 1 -4 � I � 4- 1 1 -4 4- 1 1 - 0.012- — 0008 rt l l l rt fi rt ! 0.0061'z — 0.004 — — — 0.002 / 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 Time (hours) Proposed Conditions_Resub. 2015-03-27 Type 111 24-hr 2-Year Rainfall=3.20" Prepared by {enter your company name here) Printed 3/26/2015 HydroCADO 10.00 s/n 04881 ©2011 HydroCAD Software Solutions LLC Paqe 10 Summary for Subcatchment PR-4: SW Site Runoff = 1.74 cfs @ 12.09 hrs, Volume= 0.134 af, Depth> 2.64" Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs Type III 24-hr 2-Year Rainfall=3.20" Area (sf) CN Description 1,511 39 >75% Grass cover, Good, HSG A 24,982 98 Paved parking, HSG A 26,493 95 Weighted Average 1,511 5.70% Pervious Area 24,982 94.30% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment PR-4: SW Site Hydrograph 1.74 CfS ❑Runoff �y�e III 241-h� I I I �-) fear Rainfali=�.20" I Runoff Area=26,493 slf I Runoff Vollume=e.11341 aid unof Delpt~1�12.74v1 c=6.0 min 6NL95 0 ..,�.,�..�,.�:..�,.,�,.,,, „ 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 Time (hours) Proposed Conditions_Resub. 2015-03-27 Type 111 24-hr 2-Year Rainfall=3.20" Prepared by {enter your company name here) Printed 3/26/2015 HydroCADO 10.00 s/n 04881 ©2011 HydroCAD Software Solutions LLC Paqe 11 Summary for Subcatchment PR-5: S Site Not Detained Runoff = 0.56 cfs @ 12.09 hrs, Volume= 0.042 af, Depth> 2.44" Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs Type III 24-hr 2-Year Rainfall=3.20" Area (sf) CN Description 746 39 >75% Grass cover, Good, HSG A 8,286 98 Paved parkin❑, HSG A 9,032 93 Weighted Average 746 8.26% Pervious Area 8,286 91.74% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment PR-5: S Site Not Detained Hydrograph 0.6--�/ ❑Runoff 0.56 cfs 0.55�-/ iy�e- 11-1-f24-hr + 0.5� 2�- aura I�nall= 2b 0.45� Runoff Areas ,WZsf1 04 Runoff Volumg#.q4-? of w 0.35-->/ �U�off-p�ptll��2�4� . 0 0.3� Tc= .0-mm 02 `/ II4- II II 0.15 0.05-�'/ 0 �..�..�../....(.... :.../.. 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 Time (hours) Proposed Conditions_Resub. 2015-03-27 Type 111 24-hr 2-Year Rainfall=3.20" Prepared by {enter your company name here) Printed 3/26/2015 HydroCAD® 10.00 s/n 04881 ©2011 HydroCAD Software Solutions LLC Page 12 Summary for Pond SED: Sediment Forebay Inflow Area = 0.531 ac, 71.77% Impervious, Inflow Depth > 1.47" for 2-Year event Inflow = 0.89 cfs @ 12.10 hrs, Volume= 0.065 of Outflow = 0.15 cfs @ 12.62 hrs, Volume= 0.065 af, Atten= 83%, Lag= 31.2 min Discarded = 0.15 cfs @ 12.62 hrs, Volume= 0.065 of Primary = 0.00 cfs @ 0.00 hrs, Volume= 0.000 of Routing by Stor-Ind method, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs Peak Elev= 35.91' @ 12.62 hrs Surf.Area= 742 sf Storage= 1,029 cf Plug-Flow detention time= 77.9 min calculated for 0.065 of(99% of inflow) Center-of-Mass det. time= 76.0 min ( 914.9 - 838.9 ) Volume Invert Avail.Storage Storage Description #1 33.00' 3,422 cf Sediment Forebay (Prismatic)Listed below (Recalc) Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 33.00 1 0 0 34.00 239 120 120 35.00 474 357 477 36.00 769 622 1,098 37.00 1,132 951 2,049 38.00 1,615 1,374 3,422 Device Routinq Invert Outlet Devices #1 Discarded 33.00' 8.270 in/hr Exfiltration over Surface area Conductivity to Groundwater Elevation = 0.00' #2 Primary 35.00' 12.0" Round Culvert L= 112.0' CPP, projecting, no headwall, Ke= 0.900 Inlet/ Outlet Invert= 35.00' / 35.00' S= 0.0000 T Cc= 0.900 n= 0.013 Corrugated PE, smooth interior, Flow Area= 0.79 sf #3 Device 2 36.25' 12.0" Horiz. Orifice/Grate C= 0.600 Limited to weir flow at low heads Discarded OutFlow Max=0.15 cfs @ 12.62 hrs HW=35.91' (Free Discharge) L1=Exfiltration ( Controls 0.15 cfs) Primary OutFlow Max=0.00 cfs @ 0.00 hrs HW=33.00' (Free Discharge) L2=Culvert ( Controls 0.00 cfs) L3=Orifice/Grate ( Controls 0.00 cfs) Proposed Conditions_Resub. 2015-03-27 Type 111 24-hr 2-Year Rainfall=3.20" Prepared by {enter your company name here) Printed 3/26/2015 HydroCADO 10.00 s/n 04881 ©2011 HydroCAD Software Solutions LLC Page 13 Pond SED: Sediment Forebay Hydrograph L -L 1 -4 L-- I —L 1 1 — ■Inflow M Outflow X�ei"3'1 6 ■Primary 0.95"' I-elate Brlv*35:91 fi rt fi 0.9� / 0.85� / — 0.8 / T I : 1 4 11 1 - 0.7511/ 0 65� / + - - - =1 - - 0.6 ' 16 0.55 ' / rt 3 0.5 z 00.45 ' � I — u 0.4"' / 0.35"' / 0.25-!' 0.15 cfs � — 0.21 / 0.15� / 0.00 cfs 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 Time (hours) Proposed Conditions_Resub. 2015-03-27 Type 111 24-hr 2-Year Rainfall=3.20" Prepared by {enter your company name here) Printed 3/26/2015 HydroCAD® 10.00 s/n 04881 ©2011 HydroCAD Software Solutions LLC Page 14 Summary for Pond SSI-1: Subsurface Infiltration Basin 1-East Inflow Area = 1.580 ac, 82.97% Impervious, Inflow Depth > 2.00" for 2-Year event Inflow = 3.61 cfs @ 12.09 hrs, Volume= 0.263 of Outflow = 0.29 cfs @ 13.39 hrs, Volume= 0.262 af, Atten= 92%, Lag= 78.1 min Discarded = 0.29 cfs @ 13.39 hrs, Volume= 0.262 of Primary = 0.00 cfs @ 0.00 hrs, Volume= 0.000 of Routing by Stor-Ind method, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs Peak Elev= 29.71' @ 13.39 hrs Surf.Area= 0.111 ac Storage= 0.110 of Plug-Flow detention time= 150.3 min calculated for 0.262 of(100% of inflow) Center-of-Mass det. time= 149.0 min ( 963.5 - 814.5 ) Volume Invert Avail.Storage Storage Description #1A 28.00' 0.146 of 52.00'W x 93.00'L x 6.00'H Field A 0.666 of Overall - 0.300 of Embedded = 0.366 of x 40.0% Voids #2A 28.50' 0.300 of CMP_Round 60 x 7 Inside #1 Effective Size= 60.0"W x 60.0"H => 19.59 sf x 20.00'L = 391.8 cf Overall Size= 60.0"W x 60.0"H x 20.001 Row Length Adjustment= +61.00' x 19.59 sf x 7 rows 50.00' Header x 19.59 sf x 2 = 1,959.0 cf 0.446 of Total Available Storage Storage Group A created with Chamber Wizard Device Routinq Invert Outlet Devices #1 Discarded 28.00' 2.410 in/hr Exfiltration over Surface area Conductivity to Groundwater Elevation = 0.00' #2 Primary 33.00' 18.0" Round Culvert L= 49.0' CPP, projecting, no headwall, Ke= 0.900 Inlet/ Outlet Invert= 33.00' / 32.75' S= 0.0051 T Cc= 0.900 n= 0.013 Corrugated PE, smooth interior, Flow Area= 1.77 sf Discarded OutFlow Max=0.29 cfs @ 13.39 hrs HW=29.71' (Free Discharge) L1=Exfi1tration ( Controls 0.29 cfs) Primary OutFlow Max=0.00 cfs @ 0.00 hrs HW=28.00' (Free Discharge) L2=Culvert ( Controls 0.00 cfs) Proposed Conditions_Resub. 2015-03-27 Type 111 24-hr 2-Year Rainfall=3.20" Prepared by {enter your company name here) Printed 3/26/2015 HydroCADO 10.00 s/n 04881 ©2011 HydroCAD Software Solutions LLC Paqe 15 Pond SSI-1: Subsurface Infiltration Basin 1-East - Chamber Wizard Field A Chamber Model = CMP_Round 60 Effective Size= 60.0"W x 60.0"H => 19.59 sf x 20.001 = 391.8 cf Overall Size= 60.0"W x 60.0"H x 20.001 Row Length Adjustment= +61.00' x 19.59 sf x 7 rows 60.0" Wide + 30.0" Spacing = 90.0" C-C Row Spacing 1 Chambers/Row x 20.00' Long +61.00' Row Adjustment +5.00' Header x 2 = 91.00' Row Length +12.0" End Stone x 2 = 93.00' Base Length 7 Rows x 60.0" Wide + 30.0" Spacing x 6 + 12.0" Side Stone x 2 = 52.00' Base Width 6.0" Base + 60.0" Chamber Height + 6.0" Cover = 6.00' Field Height 7 Chambers x 391.8 cf +61.00' Row Adjustment x 19.59 sf x 7 Rows + 50.00' Header x 19.59 sf x 2 = 13,066.5 cf Chamber Storage 29,016.0 cf Field - 13,066.5 cf Chambers = 15,949.5 cf Stone x 40.0% Voids = 6,379.8 cf Stone Storage Stone + Chamber Storage = 19,446.3 cf= 0.446 of Overall Storage Efficiency = 67.0% 7 Chambers 1,074.7 cy Field 590.7 cy Stone Proposed Conditions_Resub. 2015-03-27 Type 111 24-hr 2-Year Rainfall=3.20" Prepared by {enter your company name here) Printed 3/26/2015 HydroCAD® 10.00 s/n 04881 ©2011 HydroCAD Software Solutions LLC Page 16 Pond SSI-1: Subsurface Infiltration Basin 1-East Hydrograph TI TT TIT % 3.61 cfs El Inflow /� Outflow 4— Inflow Area-1 �5$O�a ❑Prmarry Peak 81ev�--29-11� T Storage=01.1110 alf 3 / -1 TT TT T 1 IIIIIIIIIII � I � � � II ' 3 2 0 LL / 0.29 cfs � 0.00 cfs 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 Time (hours) Proposed Conditions_Resub. 2015-03-27 Type 111 24-hr 2-Year Rainfall=3.20" Prepared by {enter your company name here) Printed 3/26/2015 HydroCAD® 10.00 s/n 04881 ©2011 HydroCAD Software Solutions LLC Page 17 Summary for Pond SSI-2: Subsurface Infiltration Basin 2-South Inflow Area = 5.691 ac, 79.53% Impervious, Inflow Depth > 1.77" for 2-Year event Inflow = 11.45 cfs @ 12.09 hrs, Volume= 0.840 of Outflow = 1.30 cfs @ 12.82 hrs, Volume= 0.839 af, Atten= 89%, Lag= 43.5 min Discarded = 1.30 cfs @ 12.82 hrs, Volume= 0.839 of Primary = 0.00 cfs @ 0.00 hrs, Volume= 0.000 of Routing by Stor-Ind method, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs Peak Elev= 31.10' @ 12.82 hrs Surf.Area= 0.517 ac Storage= 0.298 of Plug-Flow detention time= 76.6 min calculated for 0.839 of(100% of inflow) Center-of-Mass det. time= 76.0 min ( 882.4 - 806.4 ) Volume Invert Avail.Storage Storage Description #1A 30.00' 0.502 of 126.50'W x 178.00'L x 4.00'H Field A 2.068 of Overall - 0.811 of Embedded = 1.256 of x 40.0% Voids #2A 30.50' 0.811 of CMP_Round 36 x 28 Inside #1 Effective Size= 36.0"W x 36.0"H => 7.06 sf x 20.00'L = 141.1 cf Overall Size= 36.0"W x 36.0"H x 20.001 Row Length Adjustment= +150.00' x 7.06 sf x 28 rows 124.50' Header x 7.06 sf x 2 = 1,757.1 cf 1.314 of Total Available Storage Storage Group A created with Chamber Wizard Device Routinq Invert Outlet Devices #1 Discarded 30.00' 2.410 in/hr Exfiltration over Surface area Conductivity to Groundwater Elevation = 0.00' #2 Primary 30.50' 15.0" Round Culvert L= 29.0' CPP, projecting, no headwall, Ke= 0.900 Inlet/ Outlet Invert= 30.50' / 30.20' S= 0.0103 '/' Cc= 0.900 n= 0.013 Corrugated PE, smooth interior, Flow Area= 1.23 sf #3 Device 2 33.40' 5.0' long Sharp-Crested Rectangular Weir 2 End Contraction(s) 2.9' Crest Height Discarded OutFlow Max=1.30 cfs @ 12.82 hrs HW=31.10' (Free Discharge) L1=Exfiltration ( Controls 1.30 cfs) Primary OutFlow Max=0.00 cfs @ 0.00 hrs HW=30.00' (Free Discharge) L2=Culvert ( Controls 0.00 cfs) L3=Sharp-Crested Rectangular Weir( Controls 0.00 cfs) Proposed Conditions_Resub. 2015-03-27 Type 111 24-hr 2-Year Rainfall=3.20" Prepared by {enter your company name here) Printed 3/26/2015 HydroCADO 10.00 s/n 04881 ©2011 HydroCAD Software Solutions LLC Paqe 18 Pond SSI-2: Subsurface Infiltration Basin 2-South - Chamber Wizard Field A Chamber Model = CMP_Round 36 Effective Size= 36.0"W x 36.0"H => 7.06 sf x 20.00'L = 141.1 cf Overall Size= 36.0"W x 36.0"H x 20.001 Row Length Adjustment= +150.00' x 7.06 sf x 28 rows 36.0" Wide + 18.0" Spacing = 54.0" C-C Row Spacing 1 Chambers/Row x 20.00' Long +150.00' Row Adjustment +3.00' Header x 2 = 176.00' Row Length +12.0" End Stone x 2 = 178.00' Base Length 28 Rows x 36.0" Wide + 18.0" Spacing x 27 + 12.0" Side Stone x 2 = 126.50' Base Width 6.0" Base + 36.0" Chamber Height + 6.0" Cover = 4.00' Field Height 28 Chambers x 141.1 cf +150.00' Row Adjustment x 7.06 sf x 28 Rows + 124.50' Header x 7.06 sf x 2 = 35,346.8 cf Chamber Storage 90,068.0 cf Field - 35,346.8 cf Chambers = 54,721.2 cf Stone x 40.0% Voids = 21,888.5 cf Stone Storage Stone + Chamber Storage = 57,235.3 cf= 1.314 of Overall Storage Efficiency = 63.5% 28 Chambers 3,335.9 cy Field 2,026.7 cy Stone Proposed Conditions_Resub. 2015-03-27 Type 111 24-hr 2-Year Rainfall=3.20" Prepared by {enter your company name here) Printed 3/26/2015 HydroCADO 10.00 s/n 04881 ©2011 HydroCAD Software Solutions LLC Paqe 19 Pond SSI-2: Subsurface Infiltration Basin 2-South Hydrograph 11.45 cfs — — — ■Inflow + L ■outflow 1 ilo—' V lke��J.IV a - �Prmaryed 11 Nall 111WV:41-1 W- 1 1 101,/ /1 StOrOge$O�29$1 af- I I + 1 fi I - 9 'IIII I_ /i -f11t11fiI - It fi 6� 'I u - 4� / A t- J t 1 t I t 31 / '� 005_. 1.30 cfs ......� 0.00 cfs 0 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 Time (hours) Proposed Conditions_Resub. 2015-03-27 Type 111 24-hr 2-Year Rainfall=3.20" Prepared by {enter your company name here) Printed 3/26/2015 HydroCAD® 10.00 s/n 04881 ©2011 HydroCAD Software Solutions LLC Page 20 Summary for Pond SSI-3: Subsurface Infiltration Basin 3-Southwest Inflow Area = 0.608 ac, 94.30% Impervious, Inflow Depth > 2.64" for 2-Year event Inflow = 1.74 cfs @ 12.09 hrs, Volume= 0.134 of Outflow = 0.28 cfs @ 12.57 hrs, Volume= 0.134 af, Atten= 84%, Lag= 29.0 min Discarded = 0.28 cfs @ 12.57 hrs, Volume= 0.134 of Primary = 0.00 cfs @ 0.00 hrs, Volume= 0.000 of Routing by Stor-Ind method, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs Peak Elev= 30.76' @ 12.57 hrs Surf.Area= 4,830 sf Storage= 1,697 cf Plug-Flow detention time= 38.1 min calculated for 0.134 of(100% of inflow) Center-of-Mass det. time= 37.8 min ( 818.3 - 780.5 ) Volume Invert Avail.Storage Storage Description #1A 30.00' 3,502 cf 46.00'W x 105.00'L x 2.50'H Field A 12,075 cf Overall - 3,320 cf Embedded = 8,755 cf x 40.0% Voids #2A 30.50' 3,320 cf CMP_Round 18 x 18 Inside #1 Effective Size= 18.0"W x 18.0"H => 1.76 sf x 20.00'L = 35.2 cf Overall Size= 18.0"W x 18.0"H x 20.001 Row Length Adjustment= +80.00' x 1.76 sf x 18 rows 44.00' Header x 1.76 sf x 2 = 154.7 cf 6,822 cf Total Available Storage Storage Group A created with Chamber Wizard Device Routinq Invert Outlet Devices #1 Discarded 30.00' 2.410 in/hr Exfiltration over Surface area Conductivity to Groundwater Elevation = 0.00' #2 Primary 30.00' 12.0" Round Culvert L= 100.0' CPP, projecting, no headwall, Ke= 0.900 Inlet/Outlet Invert= 30.00' / 29.00' S= 0.0100 '/' Cc= 0.900 n= 0.013 Corrugated PE, smooth interior, Flow Area= 0.79 sf #3 Device 2 32.30' 5.0' long Sharp-Crested Rectangular Weir 2 End Contraction(s) 1.8' Crest Height Discarded OutFlow Max=0.28 cfs @ 12.57 hrs HW=30.76' (Free Discharge) L1=Exfiltration ( Controls 0.28 cfs) Primary OutFlow Max=0.00 cfs @ 0.00 hrs HW=30.00' (Free Discharge) L2=Culvert ( Controls 0.00 cfs) L3=Sharp-Crested Rectangular Weir( Controls 0.00 cfs) Proposed Conditions_Resub. 2015-03-27 Type 111 24-hr 2-Year Rainfall=3.20" Prepared by {enter your company name here) Printed 3/26/2015 HydroCADO 10.00 s/n 04881 ©2011 HydroCAD Software Solutions LLC Paqe 21 Pond SSI-3: Subsurface Infiltration Basin 3-Southwest - Chamber Wizard Field A Chamber Model = CMP_Round 18 Effective Size= 18.0"W x 18.0"H => 1.76 sf x 20.00'L = 35.2 cf Overall Size= 18.0"W x 18.0"H x 20.001 Row Length Adjustment= +80.00' x 1.76 sf x 18 rows 18.0" Wide + 12.0" Spacing = 30.0" C-C Row Spacing 1 Chambers/Row x 20.00' Long +80.00' Row Adjustment +1.50' Header x 2 = 103.00' Row Length +12.0" End Stone x 2 = 105.00' Base Length 18 Rows x 18.0" Wide + 12.0" Spacing x 17 + 12.0" Side Stone x 2 = 46.00' Base Width 6.0" Base + 18.0" Chamber Height + 6.0" Cover = 2.50' Field Height 18 Chambers x 35.2 cf +80.00' Row Adjustment x 1.76 sf x 18 Rows + 44.00' Header x 1.76 sf x 2 = 3,319.7 cf Chamber Storage 12,075.0 cf Field - 3,319.7 cf Chambers = 8,755.3 cf Stone x 40.0% Voids = 3,502.1 cf Stone Storage Stone + Chamber Storage = 6,821.8 cf= 0.157 of Overall Storage Efficiency = 56.5% 18 Chambers 447.2 cy Field 324.3 cy Stone Proposed Conditions_Resub. 2015-03-27 Type 111 24-hr 2-Year Rainfall=3.20" Prepared by {enter your company name here) Printed 3/26/2015 HydroCAD® 10.00 s/n 04881 ©2011 HydroCAD Software Solutions LLC Page 22 Pond SSI-3: Subsurface Infiltration Basin 3-Southwest Hydrograph I ❑ inflow 1.74 CfS ❑Outflow Inflow Area=0.608 a ❑[IP Primrimaryary Peak Elev=30.76' Storage=1,697 cf LL _ IIIII 0.28 cfs 0.00 cfs 0 ++Ir"r :...1:... .... :...�����/%l%/////!%//r�%//,///��///,///( 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 Time (hours) Proposed Conditions_Resub. 2015-03-27 Type 111 24-hr 2-Year Rainfall=3.20" Prepared by {enter your company name here) Printed 3/26/2015 HydroCAD® 10.00 s/n 04881 ©2011 HydroCAD Software Solutions LLC Paqe 23 Summary for Pond SWALE: Water Quality Swale Inflow Area = 1.038 ac, 49.25% Impervious, Inflow Depth > 0.11" for 2-Year event Inflow = 0.04 cfs @ 12.36 hrs, Volume= 0.009 of Outflow = 0.04 cfs @ 12.45 hrs, Volume= 0.009 af, Atten= 8%, Lag= 5.3 min Discarded = 0.04 cfs @ 12.45 hrs, Volume= 0.009 of Primary = 0.00 cfs @ 0.00 hrs, Volume= 0.000 of Routing by Stor-Ind method, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs Peak Elev= 34.07' @ 12.45 hrs Surf.Area= 206 sf Storage= 8 cf Plug-Flow detention time= 1.7 min calculated for 0.009 of(100% of inflow) Center-of-Mass det. time= 1.3 min ( 964.5 - 963.2 ) Volume Invert Avail.Storage Storage Description #1 34.00' 9,132 cf Custom Stage Data (Prismatic)Listed below (Recalc) Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 34.00 5 0 0 35.00 2,730 1,368 1,368 36.00 3,868 3,299 4,667 37.00 5,063 4,466 9,132 Device Routinq Invert Outlet Devices #1 Discarded 34.00' 8.270 in/hr Exfiltration over Surface area Conductivity to Groundwater Elevation = 0.00' #2 Device 3 35.95' 12.0" Horiz. Orifice/Grate C= 0.600 Limited to weir flow at low heads #3 Primary 32.50' 15.0" Round Culvert L= 67.0' CPP, projecting, no headwall, Ke= 0.900 Inlet/Outlet Invert= 32.50' / 31.70' S= 0.0119 T Cc= 0.900 n= 0.013 Corrugated PE, smooth interior, Flow Area= 1.23 sf Discarded OutFlow Max=0.04 cfs @ 12.45 hrs HW=34.07' (Free Discharge) L1=Exfiltration ( Controls 0.04 cfs) Primary OutFlow Max=0.00 cfs @ 0.00 hrs HW=34.00' (Free Discharge) L Culvert (Passes 0.00 cfs of 4.36 cfs potential flow) 2=Orifice/Grate ( Controls 0.00 cfs) Proposed Conditions_Resub. 2015-03-27 Type 111 24-hr 2-Year Rainfall=3.20" Prepared by {enter your company name here) Printed 3/26/2015 HydroCAD® 10.00 s/n 04881 ©2011 HydroCAD Software Solutions LLC Paqe 24 Pond SWALE: Water Quality Swale Hydrograph ❑ Inflow 0.04 cfs I El Outflow Inflow Area=7 .03R �� L I T L — ❑Primary❑Discarded 0.045- Peak Elev=34.0 0.04 cfs 0.04-� i §tQr�ge=8 cf 0.03� y � � TITI_ITITT 0.025�'// 3 ' IIIIIIIII LL 0.02�/ — — — — — — 0.015->/ 0.01 i i 0.00 cfs 0 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 Time (hours) HYDROGRAPHS - 10 YEAR STORM Proposed Conditions_Resub. 2015-03-27 Type/1/ 24-hr 10-Year Rainfall=4.90" Prepared by {enter your company name here) Printed 3/26/2015 HydroCAD® 10.00 s/n 04881 ©2011 HydroCAD Software Solutions LLC Paoe 25 Time span=0.00-24.00 hrs, dt=0.05 hrs, 481 points Runoff by SCS TR-20 method, UH=SCS Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method Link POA-A: 18" Pipe Leaving West Side of Site Inflow=0.00 cfs 0.000 of Primary=0.00 cfs 0.000 of Link POA-B: 12" Pipe Leaving Southwest Side of Site Primary=0.00 cfs 0.000 of Link POA-C: 18" Pipe Leaving South Side of Site Inflow=0.92 cfs 0.071 of Primary=0.92 cfs 0.071 of SubcatchmentPR-1: NE Site Runoff Area=68,842 sf 82.97% Impervious Runoff Depth>3.57" Tc=6.0 min CN=88 Runoff=6.33 cfs 0.470 of SubcatchmentPR-2: S Site and Roof Runoff Area=202,664 sf 86.29% Impervious Runoff Depth>3.78" Tc=6.0 min CN=90 Runoff=19.47 cfs 1.464 of SubcatchmentPR-3A: E Site Parking Runoff Area=23,125 sf 71.77% Impervious Runoff Depth>2.89" Tc=6.0 min CN=81 Runoff=1.77 cfs 0.128 of SubcatchmentPR-3B: E Site Runoff Area=22,103 sf 25.70% Impervious Runoff Depth>0.87" Tc=6.0 min CN=54 Runoff=0.39 cfs 0.037 of SubcatchmentPR-4: SW Site Runoff Area=26,493 sf 94.30% Impervious Runoff Depth>4.32" Tc=6.0 min CN=95 Runoff=2.77 cfs 0.219 of SubcatchmentPR-5: S Site Not Detained Runoff Area=9,032 sf 91.74% Impervious Runoff Depth>4.10" Tc=6.0 min CN=93 Runoff=0.92 cfs 0.071 of Pond SED: Sediment Forebay Peak Elev=36.46' Storage=1,494 cf Inflow=1.77 cfs 0.128 of Discarded=0.19 cfs 0.102 of Primary=1.02 cfs 0.026 of Outflow=1.21 cfs 0.127 of Pond SSI-1: Subsurface Infiltration Basin Peak Elev=31.18' Storage=0.239 of Inflow=6.33 cfs 0.470 of Discarded=0.30 cfs 0.360 of Primary=0.00 cfs 0.000 of Outflow=0.30 cfs 0.360 of Pond SSI-2: Subsurface Infiltration Basin Peak Elev=31.93' Storage=0.626 of Inflow=19.47 cfs 1.464 of Discarded=1.34 cfs 1.463 of Primary=0.00 cfs 0.000 of Outflow=1.34 cfs 1.463 of Pond SSI-3: Subsurface Infiltration Basin Peak Elev=31.22' Storage=3,314 cf Inflow=2.77 cfs 0.219 of Discarded=0.28 cfs 0.219 of Primary=0.00 cfs 0.000 of Outflow=0.28 cfs 0.219 of Pond SWALE:Water Quality Swale Peak Elev=34.80' Storage=879 cf Inflow=1.32 cfs 0.062 of Discarded=0.42 cfs 0.062 of Primary=0.00 cfs 0.000 of Outflow=0.42 cfs 0.062 of Total Runoff Area = 8.087 ac Runoff Volume = 2.389 of Average Runoff Depth = 3.55" 18.37% Pervious = 1.486 ac 81.63% Impervious = 6.601 ac Proposed Conditions_Resub. 2015-03-27 Type 111 24-hr 10-Year Rainfall=4.90" Prepared by {enter your company name here) Printed 3/26/2015 HydroCADO 10.00 s/n 04881 ©2011 HydroCAD Software Solutions LLC Paqe 26 Summary for Link POA-A: 18" Pipe Leaving West Side of Site Inflow Area = 5.691 ac, 79.53% Impervious, Inflow Depth = 0.00" for 10-Year event Inflow = 0.00 cfs @ 0.00 hrs, Volume= 0.000 of Primary = 0.00 cfs @ 0.00 hrs, Volume= 0.000 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs Link POA-A: 18" Pipe Leaving West Side of Site Hydrograph �I i C Inflow 1 ddd I❑Primaryll 1410�N IAA e6=�5.691 lad illllllll II IIlll � llllllllll � i II 3 0 LL 0.00 cfs 0 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 Time (hours) Proposed Conditions_Resub. 2015-03-27 Type/1/ 24-hr 10-Year Rainfall=4.90" Prepared by {enter your company name here) Printed 3/26/2015 HydroCAD® 10.00 s/n 04881 ©2011 HydroCAD Software Solutions LLC Paqe 27 Summary for Link POA-B: 12" Pipe Leaving Southwest Side of Site [43] Hint: Has no inflow (Outflow=Zero) Primary = 0.00 cfs @ 0.00 hrs, Volume= 0.000 of Primary outflow = Inflow, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs Link POA-B: 12" Pipe Leaving Southwest Side of Site Hydrograph 1 ❑Primary w - i 3 0 LL 0.00 cfs 0 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 Time (hours) Proposed Conditions_Resub. 2015-03-27 Type 111 24-hr 10-Year Rainfall=4.90" Prepared by {enter your company name here) Printed 3/26/2015 HydroCADO 10.00 s/n 04881 ©2011 HydroCAD Software Solutions LLC Paqe 28 Summary for Link POA-C: 18" Pipe Leaving South Side of Site Inflow Area = 2.396 ac, 86.61% Impervious, Inflow Depth > 0.35" for 10-Year event Inflow = 0.92 cfs @ 12.09 hrs, Volume= 0.071 of Primary = 0.92 cfs @ 12.09 hrs, Volume= 0.071 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs Link POA-C: 18" Pipe Leaving South Side of Site Hydrograph Inflow l nil oI v'A�e l 2,3 0.92 cfs ❑Primary IIIIIII II � II � II 3 0 LL III o 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 Time (hours) Proposed Conditions_Resub. 2015-03-27 Type 111 24-hr 10-Year Rainfall=4.90" Prepared by {enter your company name here) Printed 3/26/2015 HydroCADO 10.00 s/n 04881 ©2011 HydroCAD Software Solutions LLC Paqe 29 Summary for Subcatchment PR-1: NE Site Runoff = 6.33 cfs @ 12.09 hrs, Volume= 0.470 af, Depth> 3.57" Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs Type III 24-hr 10-Year Rainfall=4.90" Area (sf) CN Description 11,721 39 >75% Grass cover, Good, HSG A 57,121 98 Paved parking, HSG A 68,842 88 Weighted Average 11,721 17.03% Pervious Area 57,121 82.97% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment PR-1: NE Site Hydrograph ■Runoff - 6.33 cfs 1 6�1 �y�e III 241h = 1 404ear R�infa111=4.J& 5�1 Runoff Area�=68,842 slf I Runoff Vollume=9.4701 of � 4_ Znoff Delpt~ >I3.� TI ° =6.0 fll I rf 6NL8I8 1 o ..�. .......,�,,, 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 Time (hours) Proposed Conditions_Resub. 2015-03-27 Type 111 24-hr 10-Year Rainfall=4.90" Prepared by {enter your company name here) Printed 3/26/2015 HydroCADO 10.00 s/n 04881 ©2011 HydroCAD Software Solutions LLC Paqe 30 Summary for Subcatchment PR-2: S Site and Roof Runoff = 19.47 cfs @ 12.09 hrs, Volume= 1.464 af, Depth> 3.78" Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs Type III 24-hr 10-Year Rainfall=4.90" Area (sf) CN Description 96,885 98 Roofs, HSG A 27,790 39 >75% Grass cover, Good, HSG A 77,989 98 Paved parkinq, HSG A 202,664 90 Weighted Average 27,790 13.71% Pervious Area 174,874 86.29% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment PR-2: S Site and Roof Hydrograph 4— 1 1 —121 ■Runoff 20- 19.47 cfs 19 iy� IIW24-h�- - 4-17�'/1 -fl�0-�2_W1 Rain f a I I t. 0 16-/ o- 15- 1 Ru "r:daO-2OZ6"4 J01 Z Z I I I I Z 14 1RU"ff a1ur ='�46�4 — 1 � 1 1 T — ::f 13- 3 11 u7epth>38 11 4 ° 10� -6.G-Y itT 9� � fi I I fi s- �N� I � - 6- IEI ::1LI I :IE L 45� L - 3- ...,.. 0 1 2 3 4 5 6 7 .8....9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 Time (hours) Proposed Conditions_Resub. 2015-03-27 Type 111 24-hr 10-Year Rainfall=4.90" Prepared by {enter your company name here) Printed 3/26/2015 HydroCADO 10.00 s/n 04881 ©2011 HydroCAD Software Solutions LLC Paqe 31 Summary for Subcatchment PR-3A: E Site Parking Runoff = 1.77 cfs @ 12.09 hrs, Volume= 0.128 af, Depth> 2.89" Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs Type III 24-hr 10-Year Rainfall=4.90" Area (sf) CN Description 6,529 39 >75% Grass cover, Good, HSG A 16,596 98 Paved parking, HSG A 23,125 81 Weighted Average 6,529 28.23% Pervious Area 16,596 71.77% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment PR-3A: E Site Parking Hydrograph _ 1.77 cfs ❑Runoff l y�e III 241-h� 4&Year Rainfa111=4.9& Runoff Area=23,126 sf I Runoff Vollume=9.11281 of 3 1 �U�rOfMept� >F.7"'I c=6.0 min 6NL81 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 Time (hours) Proposed Conditions_Resub. 2015-03-27 Type 111 24-hr 10-Year Rainfall=4.90" Prepared by {enter your company name here) Printed 3/26/2015 HydroCADO 10.00 s/n 04881 ©2011 HydroCAD Software Solutions LLC Paqe 32 Summary for Subcatchment PR-3B: E Site Runoff = 0.39 cfs @ 12.11 hrs, Volume= 0.037 af, Depth> 0.87" Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs Type III 24-hr 10-Year Rainfall=4.90" Area (sf) CN Description 16,423 39 >75% Grass cover, Good, HSG A 5,680 98 Paved parking, HSG A 22,103 54 Weighted Average 16,423 74.30% Pervious Area 5,680 25.70% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment PR-3B: E Site Hydrograph -i 4- I - i i - I4 I i , I- i �- I -4LI 0.42= 0.39 cfs ■Runoff 0.4� � I 0.38- fy� I1F2'F�11r 0.34 -V-'�-CQ1=11QI� II �F.�V�,� 0.32 LZ 0.3--/ Ru fto- "rb-a022 0�f _ II ::] L I L E: L :EI L 0.28- f y(]* m(� 0.26=/ �uT"T �� - I � 4- 1 I 4 -4 � 1 0 0:22 1 "�°"�Pt 'I° 7 i I I 02 _ .°-mift 0.18 � °.161N�51 0.14�IL LIL LII L 1I � IL :E1I L LIL LI 0.12- 0.1 0.08-/1 �- --4 L I I I L 0.06 0.04-%1 4 -4 L + 4 0.02 j 0 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 Time (hours) Proposed Conditions_Resub. 2015-03-27 Type/1/ 24-hr 10-Year Rainfall=4.90" Prepared by {enter your company name here) Printed 3/26/2015 HydroCAD® 10.00 s/n 04881 ©2011 HydroCAD Software Solutions LLC Paqe 33 Summary for Subcatchment PR-4: SW Site Runoff = 2.77 cfs @ 12.09 hrs, Volume= 0.219 af, Depth> 4.32" Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs Type III 24-hr 10-Year Rainfall=4.90" Area (sf) CN Description 1,511 39 >75% Grass cover, Good, HSG A 24,982 98 Paved parking, HSG A 26,493 95 Weighted Average 1,511 5.70% Pervious Area 24,982 94.30% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment PR-4: SW Site Hydrograph 3— ❑Runoff 2.77 cfs Type III 24-hr 10-Year Rainfall=4.90" - I Runoff Area=26,493 sf 2- 1 Runoff Volume=9.219 of Runoff Depth>4.�2" LL Tc=6.0 m i n CN=95 1� 0 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 Time (hours) Proposed Conditions_Resub. 2015-03-27 Type 111 24-hr 10-Year Rainfall=4.90" Prepared by {enter your company name here) Printed 3/26/2015 HydroCADO 10.00 s/n 04881 ©2011 HydroCAD Software Solutions LLC Paqe 34 Summary for Subcatchment PR-5: S Site Not Detained Runoff = 0.92 cfs @ 12.09 hrs, Volume= 0.071 af, Depth> 4.10" Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs Type III 24-hr 10-Year Rainfall=4.90" Area (sf) CN Description 746 39 >75% Grass cover, Good, HSG A 8,286 98 Paved parking, HSG A 9,032 93 Weighted Average 746 8.26% Pervious Area 8,286 91.74% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment PR-5: S Site Not Detained Hydrograph i - --4 4— i ❑Runoff 0.92 cfs l y�e III 241-h� I 4&Year Rainfa111=4.90" Runoff Area=%032 8f I Runoff Vollume=e.0171 of 7unoff Dept~ >I4.10'I 3 LL c=6.0 m i n 6NL93 o . �,.�:..�,.,�,..,� „ 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 Time (hours) Proposed Conditions_Resub. 2015-03-27 Type/1/ 24-hr 10-Year Rainfall=4.90" Prepared by {enter your company name here) Printed 3/26/2015 HydroCAD® 10.00 s/n 04881 ©2011 HydroCAD Software Solutions LLC Page 35 Summary for Pond SED: Sediment Forebay Inflow Area = 0.531 ac, 71.77% Impervious, Inflow Depth > 2.89" for 10-Year event Inflow = 1.77 cfs @ 12.09 hrs, Volume= 0.128 of Outflow = 1.21 cfs @ 12.20 hrs, Volume= 0.127 af, Atten= 32%, Lag= 6.4 min Discarded = 0.19 cfs @ 12.20 hrs, Volume= 0.102 of Primary = 1.02 cfs @ 12.20 hrs, Volume= 0.026 of Routing by Stor-Ind method, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs Peak Elev= 36.46' @ 12.20 hrs Surf.Area= 937 sf Storage= 1,494 cf Plug-Flow detention time= 74.0 min calculated for 0.127 of(99% of inflow) Center-of-Mass det. time= 70.8 min ( 890.2 - 819.4 ) Volume Invert Avail.Storage Storage Description #1 33.00' 3,422 cf Sediment Forebay (Prismatic)Listed below (Recalc) Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 33.00 1 0 0 34.00 239 120 120 35.00 474 357 477 36.00 769 622 1,098 37.00 1,132 951 2,049 38.00 1,615 1,374 3,422 Device Routinq Invert Outlet Devices #1 Discarded 33.00' 8.270 in/hr Exfiltration over Surface area Conductivity to Groundwater Elevation = 0.00' #2 Primary 35.00' 12.0" Round Culvert L= 112.0' CPP, projecting, no headwall, Ke= 0.900 Inlet/ Outlet Invert= 35.00' / 35.00' S= 0.0000 T Cc= 0.900 n= 0.013 Corrugated PE, smooth interior, Flow Area= 0.79 sf #3 Device 2 36.25' 12.0" Horiz. Orifice/Grate C= 0.600 Limited to weir flow at low heads Discarded OutFlow Max=0.19 cfs @ 12.20 hrs HW=36.46' (Free Discharge) L1=Exfiltration ( Controls 0.19 cfs) Primary OutFlow Max=1.01 cfs @ 12.20 hrs HW=36.46' (Free Discharge) L2=Culvert (Passes 1.01 cfs of 1.84 cfs potential flow) L3=Orifice/Grate (Weir Controls 1.01 cfs @ 1.51 fps) Proposed Conditions_Resub. 2015-03-27 Type/1/ 24-hr 10-Year Rainfall=4.90" Prepared by {enter your company name here) Printed 3/26/2015 HydroCAD® 10.00 s/n 04881 ©2011 HydroCAD Software Solutions LLC Paqe 36 Pond SED: Sediment Forebay Hydrograph 1.77 cfs ❑ inflow ❑Outflow Inflow Area=0.531 a [IPrmaryed Peak Elev=36.46' Storage=1,494 cf 1.21 cfs N 1.02 cfs] V 3 1 U. 0 cfs 0 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 Time (hours) Proposed Conditions_Resub. 2015-03-27 Type/1/ 24-hr 10-Year Rainfall=4.90" Prepared by {enter your company name here) Printed 3/26/2015 HydroCAD® 10.00 s/n 04881 ©2011 HydroCAD Software Solutions LLC Page 37 Summary for Pond SSI-1: Subsurface Infiltration Basin 1-East Inflow Area = 1.580 ac, 82.97% Impervious, Inflow Depth > 3.57" for 10-Year event Inflow = 6.33 cfs @ 12.09 hrs, Volume= 0.470 of Outflow = 0.30 cfs @ 14.76 hrs, Volume= 0.360 af, Atten= 95%, Lag= 160.4 min Discarded = 0.30 cfs @ 14.76 hrs, Volume= 0.360 of Primary = 0.00 cfs @ 0.00 hrs, Volume= 0.000 of Routing by Stor-Ind method, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs Peak Elev= 31.18' @ 14.76 hrs Surf.Area= 0.111 ac Storage= 0.239 of Plug-Flow detention time= 275.0 min calculated for 0.360 of(76% of inflow) Center-of-Mass det. time= 193.7 min ( 991.9 - 798.1 ) Volume Invert Avail.Storage Storage Description #1A 28.00' 0.146 of 52.00'W x 93.00'L x 6.00'H Field A 0.666 of Overall - 0.300 of Embedded = 0.366 of x 40.0% Voids #2A 28.50' 0.300 of CMP_Round 60 x 7 Inside #1 Effective Size= 60.0"W x 60.0"H => 19.59 sf x 20.00'L = 391.8 cf Overall Size= 60.0"W x 60.0"H x 20.001 Row Length Adjustment= +61.00' x 19.59 sf x 7 rows 50.00' Header x 19.59 sf x 2 = 1,959.0 cf 0.446 of Total Available Storage Storage Group A created with Chamber Wizard Device Routinq Invert Outlet Devices #1 Discarded 28.00' 2.410 in/hr Exfiltration over Surface area Conductivity to Groundwater Elevation = 0.00' #2 Primary 33.00' 18.0" Round Culvert L= 49.0' CPP, projecting, no headwall, Ke= 0.900 Inlet/ Outlet Invert= 33.00' / 32.75' S= 0.0051 T Cc= 0.900 n= 0.013 Corrugated PE, smooth interior, Flow Area= 1.77 sf Discarded OutFlow Max=0.30 cfs @ 14.76 hrs HW=31.18' (Free Discharge) L1=Exfi1tration ( Controls 0.30 cfs) Primary OutFlow Max=0.00 cfs @ 0.00 hrs HW=28.00' (Free Discharge) L2=Culvert ( Controls 0.00 cfs) Proposed Conditions_Resub. 2015-03-27 Type 111 24-hr 10-Year Rainfall=4.90" Prepared by {enter your company name here) Printed 3/26/2015 HydroCADO 10.00 s/n 04881 ©2011 HydroCAD Software Solutions LLC Paqe 38 Pond SSI-1: Subsurface Infiltration Basin 1-East - Chamber Wizard Field A Chamber Model = CMP_Round 60 Effective Size= 60.0"W x 60.0"H => 19.59 sf x 20.001 = 391.8 cf Overall Size= 60.0"W x 60.0"H x 20.001 Row Length Adjustment= +61.00' x 19.59 sf x 7 rows 60.0" Wide + 30.0" Spacing = 90.0" C-C Row Spacing 1 Chambers/Row x 20.00' Long +61.00' Row Adjustment +5.00' Header x 2 = 91.00' Row Length +12.0" End Stone x 2 = 93.00' Base Length 7 Rows x 60.0" Wide + 30.0" Spacing x 6 + 12.0" Side Stone x 2 = 52.00' Base Width 6.0" Base + 60.0" Chamber Height + 6.0" Cover = 6.00' Field Height 7 Chambers x 391.8 cf +61.00' Row Adjustment x 19.59 sf x 7 Rows + 50.00' Header x 19.59 sf x 2 = 13,066.5 cf Chamber Storage 29,016.0 cf Field - 13,066.5 cf Chambers = 15,949.5 cf Stone x 40.0% Voids = 6,379.8 cf Stone Storage Stone + Chamber Storage = 19,446.3 cf= 0.446 of Overall Storage Efficiency = 67.0% 7 Chambers 1,074.7 cy Field 590.7 cy Stone Proposed Conditions_Resub. 2015-03-27 Type/1/ 24-hr 10-Year Rainfall=4.90" Prepared by {enter your company name here) Printed 3/26/2015 HydroCAD® 10.00 s/n 04881 ©2011 HydroCAD Software Solutions LLC Page 39 Pond SSI-1: Subsurface Infiltration Basin 1-East Hydrograph / 6.33 cfs ❑ Inflow❑outflow Inflow Area=1 .580 a ❑ ary ❑Primrimary� Peak Elev=31.18' U _L Storage=0.239 of 5� � II IIIIIIIIIII rt 1 t 1-1 -r t -1 t- I I 1 0.30 cfs r7 0.00 cfs 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 Time (hours) Proposed Conditions_Resub. 2015-03-27 Type/1/ 24-hr 10-Year Rainfall=4.90" Prepared by {enter your company name here) Printed 3/26/2015 HydroCAD® 10.00 s/n 04881 ©2011 HydroCAD Software Solutions LLC Page 40 Summary for Pond SSI-2: Subsurface Infiltration Basin 2-South [79] Warning: Submerged Pond SWALE Primary device # 3 OUTLET by 0.23' Inflow Area = 5.691 ac, 79.53% Impervious, Inflow Depth > 3.09" for 10-Year event Inflow = 19.47 cfs @ 12.09 hrs, Volume= 1.464 of Outflow = 1.34 cfs @ 13.57 hrs, Volume= 1.463 af, Atten= 93%, Lag= 88.8 min Discarded = 1.34 cfs @ 13.57 hrs, Volume= 1.463 of Primary = 0.00 cfs @ 0.00 hrs, Volume= 0.000 of Routing by Stor-Ind method, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs Peak Elev= 31.93' @ 13.57 hrs Surf.Area= 0.517 ac Storage= 0.626 of Plug-Flow detention time= 176.8 min calculated for 1.460 of(100% of inflow) Center-of-Mass det. time= 175.9 min ( 966.8 - 790.9 ) Volume Invert Avail.Storage Storage Description #1A 30.00' 0.502 of 126.50'W x 178.00'L x 4.00'H Field A 2.068 of Overall - 0.811 of Embedded = 1.256 of x 40.0% Voids #2A 30.50' 0.811 of CMP_Round 36 x 28 Inside #1 Effective Size= 36.0"W x 36.0"H => 7.06 sf x 20.00'L = 141.1 cf Overall Size= 36.0"W x 36.0"H x 20.001 Row Length Adjustment= +150.00' x 7.06 sf x 28 rows 124.50' Header x 7.06 sf x 2 = 1,757.1 cf 1.314 of Total Available Storage Storage Group A created with Chamber Wizard Device Routinq Invert Outlet Devices #1 Discarded 30.00' 2.410 in/hr Exfiltration over Surface area Conductivity to Groundwater Elevation = 0.00' #2 Primary 30.50' 15.0" Round Culvert L= 29.0' CPP, projecting, no headwall, Ke= 0.900 Inlet/ Outlet Invert= 30.50' /30.20' S= 0.0103 '/' Cc= 0.900 n= 0.013 Corrugated PE, smooth interior, Flow Area= 1.23 sf #3 Device 2 33.40' 5.0' long Sharp-Crested Rectangular Weir 2 End Contraction(s) 2.9' Crest Height Discarded OutFlow Max=1.34 cfs @ 13.57 hrs HW=31.93' (Free Discharge) L1=Exfiltration ( Controls 1.34 cfs) Primary OutFlow Max=0.00 cfs @ 0.00 hrs HW=30.00' (Free Discharge) L2=Culvert ( Controls 0.00 cfs) L3=Sharp-Crested Rectangular Weir( Controls 0.00 cfs) Proposed Conditions_Resub. 2015-03-27 Type 111 24-hr 10-Year Rainfall=4.90" Prepared by {enter your company name here) Printed 3/26/2015 HydroCADO 10.00 s/n 04881 ©2011 HydroCAD Software Solutions LLC Paqe 41 Pond SSI-2: Subsurface Infiltration Basin 2-South - Chamber Wizard Field A Chamber Model = CMP_Round 36 Effective Size= 36.0"W x 36.0"H => 7.06 sf x 20.00'L = 141.1 cf Overall Size= 36.0"W x 36.0"H x 20.001 Row Length Adjustment= +150.00' x 7.06 sf x 28 rows 36.0" Wide + 18.0" Spacing = 54.0" C-C Row Spacing 1 Chambers/Row x 20.00' Long +150.00' Row Adjustment +3.00' Header x 2 = 176.00' Row Length +12.0" End Stone x 2 = 178.00' Base Length 28 Rows x 36.0" Wide + 18.0" Spacing x 27 + 12.0" Side Stone x 2 = 126.50' Base Width 6.0" Base + 36.0" Chamber Height + 6.0" Cover = 4.00' Field Height 28 Chambers x 141.1 cf +150.00' Row Adjustment x 7.06 sf x 28 Rows + 124.50' Header x 7.06 sf x 2 = 35,346.8 cf Chamber Storage 90,068.0 cf Field - 35,346.8 cf Chambers = 54,721.2 cf Stone x 40.0% Voids = 21,888.5 cf Stone Storage Stone + Chamber Storage = 57,235.3 cf= 1.314 of Overall Storage Efficiency = 63.5% 28 Chambers 3,335.9 cy Field 2,026.7 cy Stone Proposed Conditions_Resub. 2015-03-27 Type 111 24-hr 10-Year Rainfall=4.90" Prepared by {enter your company name here) Printed 3/26/2015 HydroCADO 10.00 s/n 04881 ©2011 HydroCAD Software Solutions LLC Page 42 Pond SSI-2: Subsurface Infiltration Basin 2-South Hydrograph 4 11 11 — — 4 �--1 + 1 4— 1 --� ❑ Inflow 19.47 Cfsl � C ❑Discarded / / la/�• 71�C� �/•�/ Q ❑Primary 20f 19,V1s� / 16/1 / / — — — — — — - - - 14� / 13� 3 / /11// / - LL191/ I t 1 fi1 1 t 1 films 8- / / 6/ / / 5 4=f / 1.34 cfs 3� / 0.00 cfs /////(i(////(il�///(/,���/���//���//��///�//////(/���///(//r'(//�� 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 Time (hours) Proposed Conditions_Resub. 2015-03-27 Type/1/ 24-hr 10-Year Rainfall=4.90" Prepared by {enter your company name here) Printed 3/26/2015 HydroCAD® 10.00 s/n 04881 ©2011 HydroCAD Software Solutions LLC Page 43 Summary for Pond SSI-3: Subsurface Infiltration Basin 3-Southwest Inflow Area = 0.608 ac, 94.30% Impervious, Inflow Depth > 4.32" for 10-Year event Inflow = 2.77 cfs @ 12.09 hrs, Volume= 0.219 of Outflow = 0.28 cfs @ 12.85 hrs, Volume= 0.219 af, Atten= 90%, Lag= 46.0 min Discarded = 0.28 cfs @ 12.85 hrs, Volume= 0.219 of Primary = 0.00 cfs @ 0.00 hrs, Volume= 0.000 of Routing by Stor-Ind method, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs Peak Elev= 31.22' @ 12.85 hrs Surf.Area= 4,830 sf Storage= 3,314 cf Plug-Flow detention time= 84.0 min calculated for 0.218 of(100% of inflow) Center-of-Mass det. time= 83.5 min ( 851.8 - 768.3 ) Volume Invert Avail.Storage Storage Description #1A 30.00' 3,502 cf 46.00'W x 105.00'L x 2.50'H Field A 12,075 cf Overall - 3,320 cf Embedded = 8,755 cf x 40.0% Voids #2A 30.50' 3,320 cf CMP_Round 18 x 18 Inside #1 Effective Size= 18.0"W x 18.0"H => 1.76 sf x 20.00'L = 35.2 cf Overall Size= 18.0"W x 18.0"H x 20.001 Row Length Adjustment= +80.00' x 1.76 sf x 18 rows 44.00' Header x 1.76 sf x 2 = 154.7 cf 6,822 cf Total Available Storage Storage Group A created with Chamber Wizard Device Routinq Invert Outlet Devices #1 Discarded 30.00' 2.410 in/hr Exfiltration over Surface area Conductivity to Groundwater Elevation = 0.00' #2 Primary 30.00' 12.0" Round Culvert L= 100.0' CPP, projecting, no headwall, Ke= 0.900 Inlet/Outlet Invert= 30.00' / 29.00' S= 0.0100 '/' Cc= 0.900 n= 0.013 Corrugated PE, smooth interior, Flow Area= 0.79 sf #3 Device 2 32.30' 5.0' long Sharp-Crested Rectangular Weir 2 End Contraction(s) 1.8' Crest Height Discarded OutFlow Max=0.28 cfs @ 12.85 hrs HW=31.22' (Free Discharge) L1=Exfiltration ( Controls 0.28 cfs) Primary OutFlow Max=0.00 cfs @ 0.00 hrs HW=30.00' (Free Discharge) L2=Culvert ( Controls 0.00 cfs) L3=Sharp-Crested Rectangular Weir( Controls 0.00 cfs) Proposed Conditions_Resub. 2015-03-27 Type 111 24-hr 10-Year Rainfall=4.90" Prepared by {enter your company name here) Printed 3/26/2015 HydroCADO 10.00 s/n 04881 ©2011 HydroCAD Software Solutions LLC Paqe 44 Pond SSI-3: Subsurface Infiltration Basin 3-Southwest - Chamber Wizard Field A Chamber Model = CMP_Round 18 Effective Size= 18.0"W x 18.0"H => 1.76 sf x 20.00'L = 35.2 cf Overall Size= 18.0"W x 18.0"H x 20.001 Row Length Adjustment= +80.00' x 1.76 sf x 18 rows 18.0" Wide + 12.0" Spacing = 30.0" C-C Row Spacing 1 Chambers/Row x 20.00' Long +80.00' Row Adjustment +1.50' Header x 2 = 103.00' Row Length +12.0" End Stone x 2 = 105.00' Base Length 18 Rows x 18.0" Wide + 12.0" Spacing x 17 + 12.0" Side Stone x 2 = 46.00' Base Width 6.0" Base + 18.0" Chamber Height + 6.0" Cover = 2.50' Field Height 18 Chambers x 35.2 cf +80.00' Row Adjustment x 1.76 sf x 18 Rows + 44.00' Header x 1.76 sf x 2 = 3,319.7 cf Chamber Storage 12,075.0 cf Field - 3,319.7 cf Chambers = 8,755.3 cf Stone x 40.0% Voids = 3,502.1 cf Stone Storage Stone + Chamber Storage = 6,821.8 cf= 0.157 of Overall Storage Efficiency = 56.5% 18 Chambers 447.2 cy Field 324.3 cy Stone Proposed Conditions_Resub. 2015-03-27 Type/1/ 24-hr 10-Year Rainfall=4.90" Prepared by {enter your company name here) Printed 3/26/2015 HydroCAD® 10.00 s/n 04881 ©2011 HydroCAD Software Solutions LLC Page 45 Pond SSI-3: Subsurface Infiltration Basin 3-Southwest Hydrograph TT TT 1 TT 4 I El Inflow 2.77 cfs s❑Discarded 3 Inflow Area=0.608 a [IPrimary Peak Elev=31 .22' Storage=3,314 cf T T 2-� LL � II 0.28 cfs 0.00 cfs 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 Time (hours) Proposed Conditions_Resub. 2015-03-27 Type/1/ 24-hr 10-Year Rainfall=4.90" Prepared by {enter your company name here) Printed 3/26/2015 HydroCAD® 10.00 s/n 04881 ©2011 HydroCAD Software Solutions LLC Paqe 46 Summary for Pond SWALE: Water Quality Swale Inflow Area = 1.038 ac, 49.25% Impervious, Inflow Depth > 0.72" for 10-Year event Inflow = 1.32 cfs @ 12.19 hrs, Volume= 0.062 of Outflow = 0.42 cfs @ 12.52 hrs, Volume= 0.062 af, Atten= 68%, Lag= 19.9 min Discarded = 0.42 cfs @ 12.52 hrs, Volume= 0.062 of Primary = 0.00 cfs @ 0.00 hrs, Volume= 0.000 of Routing by Stor-Ind method, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs Peak Elev= 34.80' @ 12.52 hrs Surf.Area= 2,188 sf Storage= 879 cf Plug-Flow detention time= 19.1 min calculated for 0.062 of(100% of inflow) Center-of-Mass det. time= 18.9 min ( 852.5 - 833.6 ) Volume Invert Avail.Storage Storage Description #1 34.00' 9,132 cf Custom Stage Data (Prismatic)Listed below (Recalc) Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 34.00 5 0 0 35.00 2,730 1,368 1,368 36.00 3,868 3,299 4,667 37.00 5,063 4,466 9,132 Device Routinq Invert Outlet Devices #1 Discarded 34.00' 8.270 in/hr Exfiltration over Surface area Conductivity to Groundwater Elevation = 0.00' #2 Device 3 35.95' 12.0" Horiz. Orifice/Grate C= 0.600 Limited to weir flow at low heads #3 Primary 32.50' 15.0" Round Culvert L= 67.0' CPP, projecting, no headwall, Ke= 0.900 Inlet/Outlet Invert= 32.50' / 31.70' S= 0.0119 T Cc= 0.900 n= 0.013 Corrugated PE, smooth interior, Flow Area= 1.23 sf Discarded OutFlow Max=0.42 cfs @ 12.52 hrs HW=34.80' (Free Discharge) L1=Exfiltration ( Controls 0.42 cfs) Primary OutFlow Max=0.00 cfs @ 0.00 hrs HW=34.00' (Free Discharge) L Culvert (Passes 0.00 cfs of 4.36 cfs potential flow) 2=Orifice/Grate ( Controls 0.00 cfs) Proposed Conditions_Resub. 2015-03-27 Type/1/ 24-hr 10-Year Rainfall=4.90" Prepared by {enter your company name here) Printed 3/26/2015 HydroCAD® 10.00 s/n 04881 ©2011 HydroCAD Software Solutions LLC Page 47 Pond SWALE: Water Quality Swale Hydrograph 1.32 cfs o Ou�tflloow llnilolwlArea�l10�8'ac l l l l l l [IPrmaryed P6ak 5I6v:�314.80' Stbr�age:�-8179 Of y IIIIIIIIIII I � � � � I ' U. IIIIIIII 0.42 cfs IIIIIIIII 0.00 cfs ... .... .... .. . . 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 Time (hours) HYDROGRAPHS - 25 YEAR STORM Proposed Conditions_Resub. 2015-03-27 Type 111 24-hr 25-Year Rainfall=6.20" Prepared by {enter your company name here) Printed 3/26/2015 HydroCAD® 10.00 s/n 04881 ©2011 HydroCAD Software Solutions LLC Page 48 Time span=0.00-24.00 hrs, dt=0.05 hrs, 481 points Runoff by SCS TR-20 method, UH=SCS Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method Link POA-A: 18" Pipe Leaving West Side of Site Inflow=0.00 cfs 0.000 of Primary=0.00 cfs 0.000 of Link POA-B: 12" Pipe Leaving Southwest Side of Site Primary=0.00 cfs 0.000 of Link POA-C: 18" Pipe Leaving South Side of Site Inflow=1.18 cfs 0.093 of Primary=1.18 cfs 0.093 of SubcatchmentPR-1: NE Site Runoff Area=68,842 sf 82.97% Impervious Runoff Depth>4.82" Tc=6.0 min CN=88 Runoff=8.41 cfs 0.634 of SubcatchmentPR-2: S Site and Roof Runoff Area=202,664 sf 86.29% Impervious Runoff Depth>5.04" Tc=6.0 min CN=90 Runoff=25.55 cfs 1.953 of SubcatchmentPR-3A: E Site Parking Runoff Area=23,125 sf 71.77% Impervious Runoff Depth>4.06" Tc=6.0 min CN=81 Runoff=2.46 cfs 0.180 of SubcatchmentPR-3B: E Site Runoff Area=22,103 sf 25.70% Impervious Runoff Depth>1.55" Tc=6.0 min CN=54 Runoff=0.81 cfs 0.066 of SubcatchmentPR-4: SW Site Runoff Area=26,493 sf 94.30% Impervious Runoff Depth>5.61" Tc=6.0 min CN=95 Runoff=3.54 cfs 0.284 of SubcatchmentPR-5: S Site Not Detained Runoff Area=9,032 sf 91.74% Impervious Runoff Depth>5.38" Tc=6.0 min CN=93 Runoff=1.18 cfs 0.093 of Pond SED: Sediment Forebay Peak Elev=36.59' Storage=1,619 cf Inflow=2.46 cfs 0.180 of Discarded=0.20 cfs 0.122 of Primary=2.05 cfs 0.056 of Outflow=2.25 cfs 0.178 of Pond SSI-1: Subsurface Infiltration Basin Peak Elev=32.51' Storage=0.355 of Inflow=8.41 cfs 0.634 of Discarded=0.31 cfs 0.393 of Primary=0.00 cfs 0.000 of Outflow=0.31 cfs 0.393 of Pond SSI-2: Subsurface Infiltration Basin Peak Elev=32.65' Storage=0.922 of Inflow=25.55 cfs 1.953 of Discarded=1.37 cfs 1.691 of Primary=0.00 cfs 0.000 of Outflow=1.37 cfs 1.691 of Pond SSI-3: Subsurface Infiltration Basin Peak Elev=31.61' Storage=4,705 cf Inflow=3.54 cfs 0.284 of Discarded=0.28 cfs 0.284 of Primary=0.00 cfs 0.000 of Outflow=0.28 cfs 0.284 of Pond SWALE:Water Quality Swale Peak Elev=35.28' Storage=2,170 cf Inflow=2.90 cfs 0.122 of Discarded=0.59 cfs 0.122 of Primary=0.00 cfs 0.000 of Outflow=0.59 cfs 0.122 of Total Runoff Area = 8.087 ac Runoff Volume = 3.210 of Average Runoff Depth = 4.76" 18.37% Pervious = 1.486 ac 81.63% Impervious = 6.601 ac Proposed Conditions_Resub. 2015-03-27 Type 111 24-hr 25-Year Rainfall=6.20" Prepared by {enter your company name here) Printed 3/26/2015 HydroCAD® 10.00 s/n 04881 ©2011 HydroCAD Software Solutions LLC Paqe 49 Summary for Link POA-A: 18" Pipe Leaving West Side of Site Inflow Area = 5.691 ac, 79.53% Impervious, Inflow Depth = 0.00" for 25-Year event Inflow = 0.00 cfs @ 0.00 hrs, Volume= 0.000 of Primary = 0.00 cfs @ 0.00 hrs, Volume= 0.000 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs Link POA-A: 18" Pipe Leaving West Side of Site Hydrograph / ❑Inflow 1 ❑Primary Inflow Area=5.691 ac N V 3 0 0.00 cfs 0 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 Time (hours) Proposed Conditions_Resub. 2015-03-27 Type 111 24-hr 25-Year Rainfall=6.20" Prepared by {enter your company name here) Printed 3/26/2015 HydroCAD® 10.00 s/n 04881 ©2011 HydroCAD Software Solutions LLC Paqe 50 Summary for Link POA-B: 12" Pipe Leaving Southwest Side of Site [43] Hint: Has no inflow (Outflow=Zero) Primary = 0.00 cfs @ 0.00 hrs, Volume= 0.000 of Primary outflow = Inflow, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs Link POA-B: 12" Pipe Leaving Southwest Side of Site Hydrograph 1 ❑Primary w - i 3 0 LL 0.00 cfs 0 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 Time (hours) Proposed Conditions_Resub. 2015-03-27 Type 111 24-hr 25-Year Rainfall=6.20" Prepared by {enter your company name here) Printed 3/26/2015 HydroCAD® 10.00 s/n 04881 ©2011 HydroCAD Software Solutions LLC Paqe 51 Summary for Link POA-C: 18" Pipe Leaving South Side of Site Inflow Area = 2.396 ac, 86.61% Impervious, Inflow Depth > 0.47" for 25-Year event Inflow = 1.18 cfs @ 12.09 hrs, Volume= 0.093 of Primary = 1.18 cfs @ 12.09 hrs, Volume= 0.093 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs Link POA-C: 18" Pipe Leaving South Side of Site Hydrograph / ❑Inflow ❑Primary Inflow Area=2.3 1.18 cfs 1� N V 3 0 LL 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 Time (hours) Proposed Conditions_Resub. 2015-03-27 Type 111 24-hr 25-Year Rainfall=6.20" Prepared by {enter your company name here) Printed 3/26/2015 HydroCADO 10.00 s/n 04881 ©2011 HydroCAD Software Solutions LLC Paqe 52 Summary for Subcatchment PR-1: NE Site Runoff = 8.41 cfs @ 12.09 hrs, Volume= 0.634 af, Depth> 4.82" Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs Type III 24-hr 25-Year Rainfall=6.20" Area (sf) CN Description 11,721 39 >75% Grass cover, Good, HSG A 57,121 98 Paved parkin❑, HSG A 68,842 88 Weighted Average 11,721 17.03% Pervious Area 57,121 82.97% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment PR-1: NE Site Hydrograph ❑Runoff 8.41 cfs $�I iy�e III 241-h�1 -i 1 7�1 �-5-dear Rainfah4.�00 —1 — Runoff Area --68,842 slf 6-:-/1 P�unoff Vollume=9.61 41 aid 5� u�off Delpt�>I4.�2'I 3 o - �C-6.0-miry L I I 2 1- o ..1..�..�:.. ....i.. 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 Time (hours) Proposed Conditions_Resub. 2015-03-27 Type 111 24-hr 25-Year Rainfall=6.20" Prepared by {enter your company name here) Printed 3/26/2015 HydroCADO 10.00 s/n 04881 ©2011 HydroCAD Software Solutions LLC Paqe 53 Summary for Subcatchment PR-2: S Site and Roof Runoff = 25.55 cfs @ 12.09 hrs, Volume= 1.953 af, Depth> 5.04" Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs Type III 24-hr 25-Year Rainfall=6.20" Area (sf) CN Description 96,885 98 Roofs, HSG A 27,790 39 >75% Grass cover, Good, HSG A 77,989 98 Paved parkinq, HSG A 202,664 90 Weighted Average 27,790 13.71% Pervious Area 174,874 86.29% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment PR-2: S Site and Roof / Hydrograph 28� + ❑Runoff 26� / 25.55 cfs 24T 7�e I W2� 221�/ �5-�ea-r�Rai 4 I I 20T1 Runoff Area=202;664 Isf N 16 1 $uljo"O]UMtip=�_9p10° 4- 14T " i t5 2� =6.�-rYl 11T 10� N�9� — 8� TIT T T TT IT T 1 T T 4� 0 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 Time (hours) Proposed Conditions_Resub. 2015-03-27 Type 111 24-hr 25-Year Rainfall=6.20" Prepared by {enter your company name here) Printed 3/26/2015 HydroCADO 10.00 s/n 04881 ©2011 HydroCAD Software Solutions LLC Paqe 54 Summary for Subcatchment PR-3A: E Site Parking Runoff = 2.46 cfs @ 12.09 hrs, Volume= 0.180 af, Depth> 4.06" Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs Type III 24-hr 25-Year Rainfall=6.20" Area (sf) CN Description 6,529 39 >75% Grass cover, Good, HSG A 16,596 98 Paved parkin❑, HSG A 23,125 81 Weighted Average 6,529 28.23% Pervious Area 16,596 71.77% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment PR-3A: E Site Parking Hydrograph ❑Runoff 2.46 cfs 1 l y�e III 241-h� 1 2154ear RiinffaII4.$& 2-1 Runoff Area�=23,125 slf 1 Runoff Vollume=Q.1801 of 7unoff Dept~ >I4.96'I 3 c=6.0 m i n 1� �N�811 - o ..�..�..�..�. 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 Time (hours) Proposed Conditions_Resub. 2015-03-27 Type 111 24-hr 25-Year Rainfall=6.20" Prepared by {enter your company name here) Printed 3/26/2015 HydroCADO 10.00 s/n 04881 ©2011 HydroCAD Software Solutions LLC Paqe 55 Summary for Subcatchment PR-3B: E Site Runoff = 0.81 cfs @ 12.11 hrs, Volume= 0.066 af, Depth> 1.55" Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs Type III 24-hr 25-Year Rainfall=6.20" Area (sf) CN Description 16,423 39 >75% Grass cover, Good, HSG A 5,680 98 Paved parking, HSG A 22,103 54 Weighted Average 16,423 74.30% Pervious Area 5,680 25.70% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment PR-3B: E Site Hydrograph 0.9 / I -7 F 1 —I F F F F ■Runoff 0.85=- 0.81 cfs 0.8� jy 111 2 h1r rt l fi l 1 rt l fi l 0o, 5-�e�aRir�fa116. O�'- - fiI 0.65� Rui}off-Arta#22,403-0 1-1 4 -4 = f f �(�T me 0.55� Ru �l-�- �uT'— �� a 3 �-/ U�O" 0.45 EO: 0.4�-/ 71c=-6-0—min 0.35�-/I �-NL54 L 1 I :1 L- :1 0.3� 0.25�'/I —F F -1 T 1 F - 0.2-!�/ + t 0.15-�/I 0.1 I _ 0.051�/ o �..�..�.. .'...�..,:.. 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 Time (hours) Proposed Conditions_Resub. 2015-03-27 Type 111 24-hr 25-Year Rainfall=6.20" Prepared by {enter your company name here) Printed 3/26/2015 HydroCAD® 10.00 s/n 04881 ©2011 HydroCAD Software Solutions LLC Paqe 56 Summary for Subcatchment PR-4: SW Site Runoff = 3.54 cfs @ 12.09 hrs, Volume= 0.284 af, Depth> 5.61" Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs Type III 24-hr 25-Year Rainfall=6.20" Area (sf) CN Description 1,511 39 >75% Grass cover, Good, HSG A 24,982 98 Paved parking, HSG A 26,493 95 Weighted Average 1,511 5.70% Pervious Area 24,982 94.30% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment PR-4: SW Site Hydrograph / ❑Runoff 3.54 cfs Type III 24-hr 1 25-Year Rainfall=6.20" 3 1 Runoff Area=26,493 sf 1 Runoff Volume=9.284 of 2_ Runoff Depth>5.� i 3 U. Tc=6.0 m i n CN=95 1- 0 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 Time (hours) Proposed Conditions_Resub. 2015-03-27 Type 111 24-hr 25-Year Rainfall=6.20" Prepared by {enter your company name here) Printed 3/26/2015 HydroCADO 10.00 s/n 04881 ©2011 HydroCAD Software Solutions LLC Paqe 57 Summary for Subcatchment PR-5: S Site Not Detained Runoff = 1.18 cfs @ 12.09 hrs, Volume= 0.093 af, Depth> 5.38" Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs Type III 24-hr 25-Year Rainfall=6.20" Area (sf) CN Description 746 39 >75% Grass cover, Good, HSG A 8,286 98 Paved parking, HSG A 9,032 93 Weighted Average 746 8.26% Pervious Area 8,286 91.74% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment PR-5: S Site Not Detained Hydrograph ❑Runoff 1.18 cfs l y�e III 241-hr 1�1 - -54-ear Rainfa111=6.$& Runoff Area=%032 0 I Runoff Vollume=e.093 of 7Unoff Dept~ >I5.�8" 3 c=6.0 m i n 6NL93 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 Time (hours) Proposed Conditions_Resub. 2015-03-27 Type 111 24-hr 25-Year Rainfall=6.20" Prepared by {enter your company name here) Printed 3/26/2015 HydroCAD® 10.00 s/n 04881 ©2011 HydroCAD Software Solutions LLC Page 58 Summary for Pond SED: Sediment Forebay Inflow Area = 0.531 ac, 71.77% Impervious, Inflow Depth > 4.06" for 25-Year event Inflow = 2.46 cfs @ 12.09 hrs, Volume= 0.180 of Outflow = 2.25 cfs @ 12.13 hrs, Volume= 0.178 af, Atten= 9%, Lag= 2.2 min Discarded = 0.20 cfs @ 12.13 hrs, Volume= 0.122 of Primary = 2.05 cfs @ 12.13 hrs, Volume= 0.056 of Routing by Stor-Ind method, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs Peak Elev= 36.59' @ 12.13 hrs Surf.Area= 985 sf Storage= 1,619 cf Plug-Flow detention time= 66.0 min calculated for 0.178 of(99% of inflow) Center-of-Mass det. time= 61.7 min ( 871.4 - 809.7 ) Volume Invert Avail.Storage Storage Description #1 33.00' 3,422 cf Sediment Forebay (Prismatic)Listed below (Recalc) Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 33.00 1 0 0 34.00 239 120 120 35.00 474 357 477 36.00 769 622 1,098 37.00 1,132 951 2,049 38.00 1,615 1,374 3,422 Device Routinq Invert Outlet Devices #1 Discarded 33.00' 8.270 in/hr Exfiltration over Surface area Conductivity to Groundwater Elevation = 0.00' #2 Primary 35.00' 12.0" Round Culvert L= 112.0' CPP, projecting, no headwall, Ke= 0.900 Inlet/ Outlet Invert= 35.00' / 35.00' S= 0.0000 T Cc= 0.900 n= 0.013 Corrugated PE, smooth interior, Flow Area= 0.79 sf #3 Device 2 36.25' 12.0" Horiz. Orifice/Grate C= 0.600 Limited to weir flow at low heads Discarded OutFlow Max=0.20 cfs @ 12.13 hrs HW=36.59' (Free Discharge) L1=Exfiltration ( Controls 0.20 cfs) Primary OutFlow Max=2.01 cfs @ 12.13 hrs HW=36.59' (Free Discharge) L2=Culvert (Passes 2.01 cfs of 2.08 cfs potential flow) L3=Orifice/Grate (Weir Controls 2.01 cfs @ 1.90 fps) Proposed Conditions_Resub. 2015-03-27 Type 111 24-hr 25-Year Rainfall=6.20" Prepared by {enter your company name here) Printed 3/26/2015 HydroCAD® 10.00 s/n 04881 ©2011 HydroCAD Software Solutions LLC Paqe 59 Pond SED: Sediment Forebay Hydrograph I El Inflow 2.46 cfs ❑Outflow El Discar Inflow Area=0.5,',%1 11 r I ❑❑Prmary d Peak Elev=36.59"2.25 cfs 4- Storage=1,611 2.05 cfs 2 U. 1 0 fs 0 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 Time (hours) Proposed Conditions_Resub. 2015-03-27 Type 111 24-hr 25-Year Rainfall=6.20" Prepared by {enter your company name here) Printed 3/26/2015 HydroCAD® 10.00 s/n 04881 ©2011 HydroCAD Software Solutions LLC Page 60 Summary for Pond SSI-1: Subsurface Infiltration Basin 1-East Inflow Area = 1.580 ac, 82.97% Impervious, Inflow Depth > 4.82" for 25-Year event Inflow = 8.41 cfs @ 12.09 hrs, Volume= 0.634 of Outflow = 0.31 cfs @ 15.47 hrs, Volume= 0.393 af, Atten= 96%, Lag= 202.8 min Discarded = 0.31 cfs @ 15.47 hrs, Volume= 0.393 of Primary = 0.00 cfs @ 0.00 hrs, Volume= 0.000 of Routing by Stor-Ind method, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs Peak Elev= 32.51' @ 15.47 hrs Surf.Area= 0.111 ac Storage= 0.355 of Plug-Flow detention time= 281.7 min calculated for 0.393 of(62% of inflow) Center-of-Mass det. time= 181.0 min ( 970.9 - 789.9 ) Volume Invert Avail.Storage Storage Description #1A 28.00' 0.146 of 52.00'W x 93.00'L x 6.00'H Field A 0.666 of Overall - 0.300 of Embedded = 0.366 of x 40.0% Voids #2A 28.50' 0.300 of CMP_Round 60 x 7 Inside #1 Effective Size= 60.0"W x 60.0"H => 19.59 sf x 20.00'L = 391.8 cf Overall Size= 60.0"W x 60.0"H x 20.001 Row Length Adjustment= +61.00' x 19.59 sf x 7 rows 50.00' Header x 19.59 sf x 2 = 1,959.0 cf 0.446 of Total Available Storage Storage Group A created with Chamber Wizard Device Routinq Invert Outlet Devices #1 Discarded 28.00' 2.410 in/hr Exfiltration over Surface area Conductivity to Groundwater Elevation = 0.00' #2 Primary 33.00' 18.0" Round Culvert L= 49.0' CPP, projecting, no headwall, Ke= 0.900 Inlet/ Outlet Invert= 33.00' / 32.75' S= 0.0051 T Cc= 0.900 n= 0.013 Corrugated PE, smooth interior, Flow Area= 1.77 sf Discarded OutFlow Max=0.31 cfs @ 15.47 hrs HW=32.51' (Free Discharge) L1=Exfi1tration ( Controls 0.31 cfs) Primary OutFlow Max=0.00 cfs @ 0.00 hrs HW=28.00' (Free Discharge) L2=Culvert ( Controls 0.00 cfs) Proposed Conditions_Resub. 2015-03-27 Type 111 24-hr 25-Year Rainfall=6.20" Prepared by {enter your company name here) Printed 3/26/2015 HydroCADO 10.00 s/n 04881 ©2011 HydroCAD Software Solutions LLC Paqe 61 Pond SSI-1: Subsurface Infiltration Basin 1-East - Chamber Wizard Field A Chamber Model = CMP_Round 60 Effective Size= 60.0"W x 60.0"H => 19.59 sf x 20.001 = 391.8 cf Overall Size= 60.0"W x 60.0"H x 20.001 Row Length Adjustment= +61.00' x 19.59 sf x 7 rows 60.0" Wide + 30.0" Spacing = 90.0" C-C Row Spacing 1 Chambers/Row x 20.00' Long +61.00' Row Adjustment +5.00' Header x 2 = 91.00' Row Length +12.0" End Stone x 2 = 93.00' Base Length 7 Rows x 60.0" Wide + 30.0" Spacing x 6 + 12.0" Side Stone x 2 = 52.00' Base Width 6.0" Base + 60.0" Chamber Height + 6.0" Cover = 6.00' Field Height 7 Chambers x 391.8 cf +61.00' Row Adjustment x 19.59 sf x 7 Rows + 50.00' Header x 19.59 sf x 2 = 13,066.5 cf Chamber Storage 29,016.0 cf Field - 13,066.5 cf Chambers = 15,949.5 cf Stone x 40.0% Voids = 6,379.8 cf Stone Storage Stone + Chamber Storage = 19,446.3 cf= 0.446 of Overall Storage Efficiency = 67.0% 7 Chambers 1,074.7 cy Field 590.7 cy Stone Proposed Conditions_Resub. 2015-03-27 Type 111 24-hr 25-Year Rainfall=6.20" Prepared by {enter your company name here) Printed 3/26/2015 HydroCAD® 10.00 s/n 04881 ©2011 HydroCAD Software Solutions LLC Page 62 Pond SSI-1: Subsurface Infiltration Basin 1-East Hydrograph 1 CfS El Inflow 8.4 lnflowlArea=l�.5 a I Outflow ❑Discarded ❑Primary � ea1 �1w3� 511� + fi 8_ StOt a Or3M alb fi I rt 7� 4->/ ,�_/ 0.31 cfs 0.00 cfs ///r%/////////////////////////////////%///////////// 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 Time (hours) Proposed Conditions_Resub. 2015-03-27 Type 111 24-hr 25-Year Rainfall=6.20" Prepared by {enter your company name here) Printed 3/26/2015 HydroCAD® 10.00 s/n 04881 ©2011 HydroCAD Software Solutions LLC Paqe 63 Summary for Pond SSI-2: Subsurface Infiltration Basin 2-South [79] Warning: Submerged Pond SWALE Primary device # 3 INLET by 0.15' Inflow Area = 5.691 ac, 79.53% Impervious, Inflow Depth > 4.12" for 25-Year event Inflow = 25.55 cfs @ 12.09 hrs, Volume= 1.953 of Outflow = 1.37 cfs @ 14.13 hrs, Volume= 1.691 af, Atten= 95%, Lag= 122.4 min Discarded = 1.37 cfs @ 14.13 hrs, Volume= 1.691 of Primary = 0.00 cfs @ 0.00 hrs, Volume= 0.000 of Routing by Stor-Ind method, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs Peak Elev= 32.65' @ 14.13 hrs Surf.Area= 0.517 ac Storage= 0.922 of Plug-Flow detention time= 251.2 min calculated for 1.691 of(87% of inflow) Center-of-Mass det. time= 192.0 min ( 975.2 - 783.2 ) Volume Invert Avail.Storage Storage Description #1A 30.00' 0.502 of 126.50'W x 178.00'L x 4.00'H Field A 2.068 of Overall - 0.811 of Embedded = 1.256 of x 40.0% Voids #2A 30.50' 0.811 of CMP_Round 36 x 28 Inside #1 Effective Size= 36.0"W x 36.0"H => 7.06 sf x 20.00'L = 141.1 cf Overall Size= 36.0"W x 36.0"H x 20.001 Row Length Adjustment= +150.00' x 7.06 sf x 28 rows 124.50' Header x 7.06 sf x 2 = 1,757.1 cf 1.314 of Total Available Storage Storage Group A created with Chamber Wizard Device Routinq Invert Outlet Devices #1 Discarded 30.00' 2.410 in/hr Exfiltration over Surface area Conductivity to Groundwater Elevation = 0.00' #2 Primary 30.50' 15.0" Round Culvert L= 29.0' CPP, projecting, no headwall, Ke= 0.900 Inlet/ Outlet Invert= 30.50' /30.20' S= 0.0103 '/' Cc= 0.900 n= 0.013 Corrugated PE, smooth interior, Flow Area= 1.23 sf #3 Device 2 33.40' 5.0' long Sharp-Crested Rectangular Weir 2 End Contraction(s) 2.9' Crest Height Discarded OutFlow Max=1.37 cfs @ 14.13 hrs HW=32.65' (Free Discharge) L1=Exfiltration ( Controls 1.37 cfs) Primary OutFlow Max=0.00 cfs @ 0.00 hrs HW=30.00' (Free Discharge) L2=Culvert ( Controls 0.00 cfs) L3=Sharp-Crested Rectangular Weir( Controls 0.00 cfs) Proposed Conditions_Resub. 2015-03-27 Type 111 24-hr 25-Year Rainfall=6.20" Prepared by {enter your company name here) Printed 3/26/2015 HydroCADO 10.00 s/n 04881 ©2011 HydroCAD Software Solutions LLC Paqe 64 Pond SSI-2: Subsurface Infiltration Basin 2-South - Chamber Wizard Field A Chamber Model = CMP_Round 36 Effective Size= 36.0"W x 36.0"H => 7.06 sf x 20.00'L = 141.1 cf Overall Size= 36.0"W x 36.0"H x 20.001 Row Length Adjustment= +150.00' x 7.06 sf x 28 rows 36.0" Wide + 18.0" Spacing = 54.0" C-C Row Spacing 1 Chambers/Row x 20.00' Long +150.00' Row Adjustment +3.00' Header x 2 = 176.00' Row Length +12.0" End Stone x 2 = 178.00' Base Length 28 Rows x 36.0" Wide + 18.0" Spacing x 27 + 12.0" Side Stone x 2 = 126.50' Base Width 6.0" Base + 36.0" Chamber Height + 6.0" Cover = 4.00' Field Height 28 Chambers x 141.1 cf +150.00' Row Adjustment x 7.06 sf x 28 Rows + 124.50' Header x 7.06 sf x 2 = 35,346.8 cf Chamber Storage 90,068.0 cf Field - 35,346.8 cf Chambers = 54,721.2 cf Stone x 40.0% Voids = 21,888.5 cf Stone Storage Stone + Chamber Storage = 57,235.3 cf= 1.314 of Overall Storage Efficiency = 63.5% 28 Chambers 3,335.9 cy Field 2,026.7 cy Stone Proposed Conditions_Resub. 2015-03-27 Type 111 24-hr 25-Year Rainfall=6.20" Prepared by {enter your company name here) Printed 3/26/2015 HydroCADO 10.00 s/n 04881 ©2011 HydroCAD Software Solutions LLC Page 65 Pond SSI-2: Subsurface Infiltration Basin 2-South Hydrograph — — — -- — iUmo25.55 cfs — — — — — — — W Discarded1 l"IA�"�5.IV� 28 Primary 26--'/' 'I yak 1tWv*3�-6 ' 22 20->/ j jl 4 1-1 4- 1-1 1 - 4 �--14- - 18. 16: — 14� � 12�'/ I t l 10 a i / 6�/ ' J 4/ ' 1.37 cfs 0.00 cfs 0 . 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 Time (hours) Proposed Conditions_Resub. 2015-03-27 Type 111 24-hr 25-Year Rainfall=6.20" Prepared by {enter your company name here) Printed 3/26/2015 HydroCAD® 10.00 s/n 04881 ©2011 HydroCAD Software Solutions LLC Page 66 Summary for Pond SSI-3: Subsurface Infiltration Basin 3-Southwest Inflow Area = 0.608 ac, 94.30% Impervious, Inflow Depth > 5.61" for 25-Year event Inflow = 3.54 cfs @ 12.09 hrs, Volume= 0.284 of Outflow = 0.28 cfs @ 13.07 hrs, Volume= 0.284 af, Atten= 92%, Lag= 59.3 min Discarded = 0.28 cfs @ 13.07 hrs, Volume= 0.284 of Primary = 0.00 cfs @ 0.00 hrs, Volume= 0.000 of Routing by Stor-Ind method, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs Peak Elev= 31.61' @ 13.07 hrs Surf.Area= 4,830 sf Storage= 4,705 cf Plug-Flow detention time= 125.8 min calculated for 0.283 of(100% of inflow) Center-of-Mass det. time= 125.2 min ( 887.6 - 762.4 ) Volume Invert Avail.Storage Storage Description #1A 30.00' 3,502 cf 46.00'W x 105.00'L x 2.50'H Field A 12,075 cf Overall - 3,320 cf Embedded = 8,755 cf x 40.0% Voids #2A 30.50' 3,320 cf CMP_Round 18 x 18 Inside #1 Effective Size= 18.0"W x 18.0"H => 1.76 sf x 20.00'L = 35.2 cf Overall Size= 18.0"W x 18.0"H x 20.001 Row Length Adjustment= +80.00' x 1.76 sf x 18 rows 44.00' Header x 1.76 sf x 2 = 154.7 cf 6,822 cf Total Available Storage Storage Group A created with Chamber Wizard Device Routinq Invert Outlet Devices #1 Discarded 30.00' 2.410 in/hr Exfiltration over Surface area Conductivity to Groundwater Elevation = 0.00' #2 Primary 30.00' 12.0" Round Culvert L= 100.0' CPP, projecting, no headwall, Ke= 0.900 Inlet/Outlet Invert= 30.00' / 29.00' S= 0.0100 '/' Cc= 0.900 n= 0.013 Corrugated PE, smooth interior, Flow Area= 0.79 sf #3 Device 2 32.30' 5.0' long Sharp-Crested Rectangular Weir 2 End Contraction(s) 1.8' Crest Height Discarded OutFlow Max=0.28 cfs @ 13.07 hrs HW=31.61' (Free Discharge) L1=Exfiltration ( Controls 0.28 cfs) Primary OutFlow Max=0.00 cfs @ 0.00 hrs HW=30.00' (Free Discharge) L2=Culvert ( Controls 0.00 cfs) L3=Sharp-Crested Rectangular Weir( Controls 0.00 cfs) Proposed Conditions_Resub. 2015-03-27 Type 111 24-hr 25-Year Rainfall=6.20" Prepared by {enter your company name here) Printed 3/26/2015 HydroCADO 10.00 s/n 04881 ©2011 HydroCAD Software Solutions LLC Paqe 67 Pond SSI-3: Subsurface Infiltration Basin 3-Southwest - Chamber Wizard Field A Chamber Model = CMP_Round 18 Effective Size= 18.0"W x 18.0"H => 1.76 sf x 20.00'L = 35.2 cf Overall Size= 18.0"W x 18.0"H x 20.001 Row Length Adjustment= +80.00' x 1.76 sf x 18 rows 18.0" Wide + 12.0" Spacing = 30.0" C-C Row Spacing 1 Chambers/Row x 20.00' Long +80.00' Row Adjustment +1.50' Header x 2 = 103.00' Row Length +12.0" End Stone x 2 = 105.00' Base Length 18 Rows x 18.0" Wide + 12.0" Spacing x 17 + 12.0" Side Stone x 2 = 46.00' Base Width 6.0" Base + 18.0" Chamber Height + 6.0" Cover = 2.50' Field Height 18 Chambers x 35.2 cf +80.00' Row Adjustment x 1.76 sf x 18 Rows + 44.00' Header x 1.76 sf x 2 = 3,319.7 cf Chamber Storage 12,075.0 cf Field - 3,319.7 cf Chambers = 8,755.3 cf Stone x 40.0% Voids = 3,502.1 cf Stone Storage Stone + Chamber Storage = 6,821.8 cf= 0.157 of Overall Storage Efficiency = 56.5% 18 Chambers 447.2 cy Field 324.3 cy Stone Proposed Conditions_Resub. 2015-03-27 Type 111 24-hr 25-Year Rainfall=6.20" Prepared by {enter your company name here) Printed 3/26/2015 HydroCAD® 10.00 s/n 04881 ©2011 HydroCAD Software Solutions LLC Page 68 Pond SSI-3: Subsurface Infiltration Basin 3-Southwest Hydrograph I ❑ inflow 3.54 cfs ❑Outflow Inflow Area=0.608 a ❑[IP Primrimaryary Peak Elev=31 .61' l i l 3 Storage=4,705 cf � IIIIIIII III 3 2- 1 7z;7, 0.28 cfs _ r 0.00 cfs 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 Time (hours) Proposed Conditions_Resub. 2015-03-27 Type 111 24-hr 25-Year Rainfall=6.20" Prepared by {enter your company name here) Printed 3/26/2015 HydroCAD® 10.00 s/n 04881 ©2011 HydroCAD Software Solutions LLC Page 69 Summary for Pond SWALE: Water Quality Swale [79] Warning: Submerged Pond SED Primary device # 2 by 0.28' Inflow Area = 1.038 ac, 49.25% Impervious, Inflow Depth > 1.41" for 25-Year event Inflow = 2.90 cfs @ 12.12 hrs, Volume= 0.122 of Outflow = 0.59 cfs @ 12.55 hrs, Volume= 0.122 af, Atten= 79%, Lag= 25.7 min Discarded = 0.59 cfs @ 12.55 hrs, Volume= 0.122 of Primary = 0.00 cfs @ 0.00 hrs, Volume= 0.000 of Routing by Stor-Ind method, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs Peak Elev= 35.28' @ 12.55 hrs Surf.Area= 3,046 sf Storage= 2,170 cf Plug-Flow detention time= 34.5 min calculated for 0.122 of(100% of inflow) Center-of-Mass det. time= 34.2 min ( 847.4 - 813.2 ) Volume Invert Avail.Storage Storage Description #1 34.00' 9,132 cf Custom Stage Data (Prismatic)Listed below (Recalc) Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 34.00 5 0 0 35.00 2,730 1,368 1,368 36.00 3,868 3,299 4,667 37.00 5,063 4,466 9,132 Device Routinq Invert Outlet Devices #1 Discarded 34.00' 8.270 in/hr Exfiltration over Surface area Conductivity to Groundwater Elevation = 0.00' #2 Device 3 35.95' 12.0" Horiz. Orifice/Grate C= 0.600 Limited to weir flow at low heads #3 Primary 32.50' 15.0" Round Culvert L= 67.0' CPP, projecting, no headwall, Ke= 0.900 Inlet/ Outlet Invert= 32.50' /31.70' S= 0.0119 T Cc= 0.900 n= 0.013 Corrugated PE, smooth interior, Flow Area= 1.23 sf Discarded OutFlow Max=0.59 cfs @ 12.55 hrs HW=35.28' (Free Discharge) L1=Exfiltration ( Controls 0.59 cfs) Primary OutFlow Max=0.00 cfs @ 0.00 hrs HW=34.00' (Free Discharge) L Culvert (Passes 0.00 cfs of 4.36 cfs potential flow) 2=Orifice/Grate ( Controls 0.00 cfs) Proposed Conditions_Resub. 2015-03-27 Type 111 24-hr 25-Year Rainfall=6.20" Prepared by {enter your company name here) Printed 3/26/2015 HydroCAD® 10.00 s/n 04881 ©2011 HydroCAD Software Solutions LLC Paqe 70 Pond SWALE: Water Quality Swale Hydrograph 2.90 cfs I ❑ Inflow ❑Outflow Inflow Area=1 .038 a ❑Discarded ❑Primary 3- Peak Elev=35.28' Storage=2,170 cf- H 4- �- ' 4 2 N w - V 3 O LL j 1 0.59 cfs 0.00 cfs 0 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 Time (hours) HYDROGRAPHS - 100 YEAR STORM Proposed Conditions_Resub. 2015-03-27 Type/1/ 24-hr 100-Year Rainfall=8.90" Prepared by {enter your company name here) Printed 3/26/2015 HydroCAD® 10.00 s/n 04881 ©2011 HydroCAD Software Solutions LLC Paoe 71 Time span=0.00-24.00 hrs, dt=0.05 hrs, 481 points Runoff by SCS TR-20 method, UH=SCS Reach routing by Stor-Ind+Trans method - Pond routing by Stor-Ind method Link POA-A: 18" Pipe Leaving West Side of Site Inflow=6.81 cfs 0.455 of Primary=6.81 cfs 0.455 of Link POA-B: 12" Pipe Leaving Southwest Side of Site Primary=0.00 cfs 0.000 of Link POA-C: 18" Pipe Leaving South Side of Site Inflow=4.54 cfs 0.399 of Primary=4.54 cfs 0.399 of SubcatchmentPR-1: NE Site Runoff Area=68,842 sf 82.97% Impervious Runoff Depth>7.44" Tc=6.0 min CN=88 Runoff=12.69 cfs 0.980 of SubcatchmentPR-2: S Site and Roof Runoff Area=202,664 sf 86.29% Impervious Runoff Depth>7.69" Tc=6.0 min CN=90 Runoff=38.05 cfs 2.981 of SubcatchmentPR-3A: E Site Parking Runoff Area=23,125 sf 71.77% Impervious Runoff Depth>6.59" Tc=6.0 min CN=81 Runoff=3.91 cfs 0.292 of SubcatchmentPR-3B: E Site Runoff Area=22,103 sf 25.70% Impervious Runoff Depth>3.29" Tc=6.0 min CN=54 Runoff=1.87 cfs 0.139 of SubcatchmentPR-4: SW Site Runoff Area=26,493 sf 94.30% Impervious Runoff Depth>8.29" Tc=6.0 min CN=95 Runoff=5.14 cfs 0.420 of SubcatchmentPR-5: S Site Not Detained Runoff Area=9,032 sf 91.74% Impervious Runoff Depth>8.05" Tc=6.0 min CN=93 Runoff=1.73 cfs 0.139 of Pond SED: Sediment Forebay Peak EIev=37.00' Storage=2,050 cf Inflow=3.91 cfs 0.292 of Discarded=0.23 cfs 0.156 of Primary=2.71 cfs 0.132 of Outflow=2.94 cfs 0.288 of Pond SSI-1: Subsurface Infiltration Basin Peak EIev=34.00' Storage=0.446 of Inflow=12.69 cfs 0.980 of Discarded=0.33 cfs 0.435 of Primary=3.02 cfs 0.224 of Outflow=3.34 cfs 0.659 of Pond SSI-2: Subsurface Infiltration Basin Peak EIev=33.96' Storage=1.305 of Inflow=38.05 cfs 3.002 of Discarded=1.42 cfs 1.875 of Primary=6.81 cfs 0.455 of Outflow=8.23 cfs 2.330 of Pond SSI-3: Subsurface Infiltration Basin Peak EIev=32.46' Storage=6,748 cf Inflow=5.14 cfs 0.420 of Discarded=0.29 cfs 0.383 of Primary=1.07 cfs 0.036 of Outflow=1.36 cfs 0.419 of Pond SWALE:Water Quality Swale Peak EIev=36.13' Storage=5,167 cf Inflow=4.46 cfs 0.271 of Discarded=0.80 cfs 0.250 of Primary=0.77 cfs 0.021 of Outflow=1.56 cfs 0.271 of Total Runoff Area = 8.087 ac Runoff Volume = 4.951 of Average Runoff Depth = 7.35" 18.37% Pervious = 1.486 ac 81.63% Impervious = 6.601 ac Proposed Conditions_Resub. 2015-03-27 Type 111 24-hr 100-Year Rainfall=8.90" Prepared by {enter your company name here) Printed 3/26/2015 HydroCADO 10.00 s/n 04881 ©2011 HydroCAD Software Solutions LLC Paqe 72 Summary for Link POA-A: 18" Pipe Leaving West Side of Site Inflow Area = 5.691 ac, 79.53% Impervious, Inflow Depth = 0.96" for 100-Year event Inflow = 6.81 cfs @ 12.52 hrs, Volume= 0.455 of Primary = 6.81 cfs @ 12.52 hrs, Volume= 0.455 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs Link POA-A: 18" Pipe Leaving West Side of Site Hydrograph l l l l Inflow ❑Primary 11nilo�v'A�ea�5.66 s.a1 cfs T I T F TI T 6 T I T TT T 5 1_ I -1 L --i L I a = 4 IIIIIIIIIII 3 0 LL I I I I 3 2 1- 0 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 Time (hours) Proposed Conditions_Resub. 2015-03-27 Type/1/ 24-hr 100-Year Rainfall=8.90" Prepared by {enter your company name here) Printed 3/26/2015 HydroCAD® 10.00 s/n 04881 ©2011 HydroCAD Software Solutions LLC Paqe 73 Summary for Link POA-B: 12" Pipe Leaving Southwest Side of Site [43] Hint: Has no inflow (Outflow=Zero) Primary = 0.00 cfs @ 0.00 hrs, Volume= 0.000 of Primary outflow = Inflow, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs Link POA-B: 12" Pipe Leaving Southwest Side of Site Hydrograph 1 ❑Primary w - i 3 0 LL 0.00 cfs 0 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 Time (hours) Proposed Conditions_Resub. 2015-03-27 Type/1/ 24-hr 100-Year Rainfall=8.90" Prepared by {enter your company name here) Printed 3/26/2015 HydroCAD® 10.00 s/n 04881 ©2011 HydroCAD Software Solutions LLC Paqe 74 Summary for Link POA-C: 18" Pipe Leaving South Side of Site Inflow Area = 2.396 ac, 86.61% Impervious, Inflow Depth > 2.00" for 100-Year event Inflow = 4.54 cfs @ 12.45 hrs, Volume= 0.399 of Primary = 4.54 cfs @ 12.45 hrs, Volume= 0.399 af, Atten= 0%, Lag= 0.0 min Primary outflow = Inflow, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs Link POA-C: 18" Pipe Leaving South Side of Site Hydrograp—h + / ❑Inflow 5� A rA rfq ❑Primary Inflow Area=2.39i 4.54 cfs 4 N _ V 3 0 LL 2 1 0 /:...r..�..�..�. .................. 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 Time (hours) Proposed Conditions_Resub. 2015-03-27 Type 111 24-hr 100-Year Rainfall=8.90" Prepared by {enter your company name here) Printed 3/26/2015 HydroCADO 10.00 s/n 04881 ©2011 HydroCAD Software Solutions LLC Paqe 75 Summary for Subcatchment PR-1: NE Site Runoff = 12.69 cfs @ 12.09 hrs, Volume= 0.980 af, Depth> 7.44" Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs Type III 24-hr 100-Year Rainfall=8.90" Area (sf) CN Description 11,721 39 >75% Grass cover, Good, HSG A 57,121 98 Paved parkin❑, HSG A 68,842 88 Weighted Average 11,721 17.03% Pervious Area 57,121 82.97% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment PR-1: NE Site Hydrograph 14� t ❑Runoff 13� 12.69 cfs 12� iy�e IIFU24--h�—I 11� 40"- e-ar kainfalT=8-.96- 1 10i-/ Runoff Area=68,842 sf l l l 9� Runoff Volume=0.980, of $� u�o�" ept�7� l L 7= Tc- .O-M In 5L-/ 4� 2 1� I -T 0=ZZ, �..�..�..�.. ....�... .. 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 Time (hours) Proposed Conditions_Resub. 2015-03-27 Type 111 24-hr 100-Year Rainfall=8.90" Prepared by {enter your company name here) Printed 3/26/2015 HydroCADO 10.00 s/n 04881 ©2011 HydroCAD Software Solutions LLC Paqe 76 Summary for Subcatchment PR-2: S Site and Roof Runoff = 38.05 cfs @ 12.09 hrs, Volume= 2.981 af, Depth> 7.69" Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs Type III 24-hr 100-Year Rainfall=8.90" Area (sf) CN Description 96,885 98 Roofs, HSG A 27,790 39 >75% Grass cover, Good, HSG A 77,989 98 Paved parkinq, HSG A 202,664 90 Weighted Average 27,790 13.71% Pervious Area 174,874 86.29% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment PR-2: S Site and Roof Hydrograph 42_//1 I I i t Runoff 38 38.05 cfs I -T T- 11 T F 34� 410( T"r F a�rrfaN�8�9b — 1 -tL- 1 1 1 1 -4 L 32- 30�-/1 Rutoff-Area=202�6641sU 1 4 �- 1 4- 1 4 -k- 28 24�1 1�ulo"ojWTp=-?.9�1 a 1- 1 -j 1 1 + 1 22 u�o"ePt�> �9 1 t I � t ° 20�i f - f1T,� '$ � --1 - —I — - I — = 1 I =1 = 1 T- N 16- 6� 14-/ 12- A LI -1 L -i LI II I I II :E 10 8-/ 4 6- 4 4 -2- 0- 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 Time (hours) Proposed Conditions_Resub. 2015-03-27 Type 111 24-hr 100-Year Rainfall=8.90" Prepared by {enter your company name here) Printed 3/26/2015 HydroCADO 10.00 s/n 04881 ©2011 HydroCAD Software Solutions LLC Paqe 77 Summary for Subcatchment PR-3A: E Site Parking Runoff = 3.91 cfs @ 12.09 hrs, Volume= 0.292 af, Depth> 6.59" Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs Type III 24-hr 100-Year Rainfall=8.90" Area (sf) CN Description 6,529 39 >75% Grass cover, Good, HSG A 16,596 98 Paved parkin❑, HSG A 23,125 81 Weighted Average 6,529 28.23% Pervious Area 16,596 71.77% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment PR-3A: E Site Parking Hydrograph ❑Runoff 4�/1 l y�e 111 24�-h cfs _ 1 1106-Year Rainfall)=6.96" 3---/1 Ru txoff-Area#-2 3,125-sf I P�unoff Vollume=9.2921 of �rolfPept�>6.19.. 2� c=6.0 m i n 6NL81 1 o ,,,,,,'.,.,i..�.,�..�,.�„��,,,�,,,,,�„ 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 Time (hours) Proposed Conditions_Resub. 2015-03-27 Type 111 24-hr 100-Year Rainfall=8.90" Prepared by {enter your company name here) Printed 3/26/2015 HydroCADO 10.00 s/n 04881 ©2011 HydroCAD Software Solutions LLC Paqe 78 Summary for Subcatchment PR-3B: E Site Runoff = 1.87 cfs @ 12.10 hrs, Volume= 0.139 af, Depth> 3.29" Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs Type III 24-hr 100-Year Rainfall=8.90" Area (sf) CN Description 16,423 39 >75% Grass cover, Good, HSG A 5,680 98 Paved parkin❑, HSG A 22,103 54 Weighted Average 16,423 74.30% Pervious Area 5,680 25.70% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment PR-3B: E Site Hydrograph 2 ❑Runoff 1.87 cfs l y�e III 241-h� I I I i 1106-Year Rainfall)=8.90" Runoff Area=22,103 sf I Runoff Vollume=Q.11391 of �U�011-13e,ptl >l- 9'� 0 1� LL c=6.0 min 6N�54 o ..�..�..�..�..,:...,:.. 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 Time (hours) Proposed Conditions_Resub. 2015-03-27 Type/1/ 24-hr 100-Year Rainfall=8.90" Prepared by {enter your company name here) Printed 3/26/2015 HydroCAD® 10.00 s/n 04881 ©2011 HydroCAD Software Solutions LLC Paqe 79 Summary for Subcatchment PR-4: SW Site Runoff = 5.14 cfs @ 12.09 hrs, Volume= 0.420 af, Depth> 8.29" Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs Type III 24-hr 100-Year Rainfall=8.90" Area (sf) CN Description 1,511 39 >75% Grass cover, Good, HSG A 24,982 98 Paved parking, HSG A 26,493 95 Weighted Average 1,511 5.70% Pervious Area 24,982 94.30% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment PR-4: SW Site Hydrograph / ❑Runoff 5.14 cfs 5- Type III 24-hr 1 100-Year Rainfall=8.90" 4- 1 Runoff Area=26,493 sf I Runoff Volume=9.420 of 3- Runoff Depth>8.?9" LL Tc=6.0 m i n 2 CN=95 o ... 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 Time (hours) Proposed Conditions_Resub. 2015-03-27 Type 111 24-hr 100-Year Rainfall=8.90" Prepared by {enter your company name here) Printed 3/26/2015 HydroCADO 10.00 s/n 04881 ©2011 HydroCAD Software Solutions LLC Paqe 80 Summary for Subcatchment PR-5: S Site Not Detained Runoff = 1.73 cfs @ 12.09 hrs, Volume= 0.139 af, Depth> 8.05" Runoff by SCS TR-20 method, UH=SCS, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs Type III 24-hr 100-Year Rainfall=8.90" Area (sf) CN Description 746 39 >75% Grass cover, Good, HSG A 8,286 98 Paved parkin❑, HSG A 9,032 93 Weighted Average 746 8.26% Pervious Area 8,286 91.74% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) (cfs) 6.0 Direct Entry, Subcatchment PR-5: S Site Not Detained Hydrograph ❑Runoff 1 7 l y�e III 241-h� . 3 cfs 406-Year Rainfall)=6.96" Runoff Area=%032 01 I Runoff Vollume=Q.11391 aid 1 i unofMelpt~ >P8 5'I 3 c=6.0 m i n 6NL93 o 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 Time (hours) Proposed Conditions_Resub. 2015-03-27 Type/1/ 24-hr 100-Year Rainfall=8.90" Prepared by {enter your company name here) Printed 3/26/2015 HydroCAD® 10.00 s/n 04881 ©2011 HydroCAD Software Solutions LLC Page 81 Summary for Pond SED: Sediment Forebay Inflow Area = 0.531 ac, 71.77% Impervious, Inflow Depth > 6.59" for 100-Year event Inflow = 3.91 cfs @ 12.09 hrs, Volume= 0.292 of Outflow = 2.94 cfs @ 12.16 hrs, Volume= 0.288 af, Atten= 25%, Lag= 4.4 min Discarded = 0.23 cfs @ 12.16 hrs, Volume= 0.156 of Primary = 2.71 cfs @ 12.16 hrs, Volume= 0.132 of Routing by Stor-Ind method, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs Peak Elev= 37.00' @ 12.16 hrs Surf.Area= 1,132 sf Storage= 2,050 cf Plug-Flow detention time= 56.1 min calculated for 0.287 of(99% of inflow) Center-of-Mass det. time= 48.5 min ( 844.7 - 796.2 ) Volume Invert Avail.Storage Storage Description #1 33.00' 3,422 cf Sediment Forebay (Prismatic)Listed below (Recalc) Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 33.00 1 0 0 34.00 239 120 120 35.00 474 357 477 36.00 769 622 1,098 37.00 1,132 951 2,049 38.00 1,615 1,374 3,422 Device Routinq Invert Outlet Devices #1 Discarded 33.00' 8.270 in/hr Exfiltration over Surface area Conductivity to Groundwater Elevation = 0.00' #2 Primary 35.00' 12.0" Round Culvert L= 112.0' CPP, projecting, no headwall, Ke= 0.900 Inlet/ Outlet Invert= 35.00' / 35.00' S= 0.0000 T Cc= 0.900 n= 0.013 Corrugated PE, smooth interior, Flow Area= 0.79 sf #3 Device 2 36.25' 12.0" Horiz. Orifice/Grate C= 0.600 Limited to weir flow at low heads Discarded OutFlow Max=0.23 cfs @ 12.16 hrs HW=36.99' (Free Discharge) L1=Exfiltration ( Controls 0.23 cfs) Primary OutFlow Max=2.69 cfs @ 12.16 hrs HW=36.99' (Free Discharge) L2=Culvert (Barrel Controls 2.69 cfs @ 3.43 fps) L3=Orifice/Grate (Passes 2.69 cfs of 3.25 cfs potential flow) Proposed Conditions_Resub. 2015-03-27 Type/1/ 24-hr 100-Year Rainfall=8.90" Prepared by {enter your company name here) Printed 3/26/2015 HydroCAD® 10.00 s/n 04881 ©2011 HydroCAD Software Solutions LLC Paqe 82 Pond SED: Sediment Forebay Hydrograph ❑ Inflow 3.91 cfs ❑outflow /� ❑Discarded 1410W IAA ea�0�5M I a [IPrimary 4� P6ak 5I6v:�317.001 Stbrage:�-2,050 Cl2.94 cfs 3� 2.71 cfs � - � � � � IIIII IIIIII 0 2� LL 1 II fs 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 Time (hours) Proposed Conditions_Resub. 2015-03-27 Type/1/ 24-hr 100-Year Rainfall=8.90" Prepared by {enter your company name here) Printed 3/26/2015 HydroCAD® 10.00 s/n 04881 ©2011 HydroCAD Software Solutions LLC Page 83 Summary for Pond SSI-1: Subsurface Infiltration Basin 1-East Inflow Area = 1.580 ac, 82.97% Impervious, Inflow Depth > 7.44" for 100-Year event Inflow = 12.69 cfs @ 12.09 hrs, Volume= 0.980 of Outflow = 3.34 cfs @ 12.46 hrs, Volume= 0.659 af, Atten= 74%, Lag= 22.1 min Discarded = 0.33 cfs @ 12.46 hrs, Volume= 0.435 of Primary = 3.02 cfs @ 12.46 hrs, Volume= 0.224 of Routing by Stor-Ind method, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs Peak Elev= 34.00' @ 12.46 hrs Surf.Area= 0.111 ac Storage= 0.446 of Plug-Flow detention time= 205.9 min calculated for 0.659 of(67% of inflow) Center-of-Mass det. time= 110.8 min ( 889.2 - 778.4 ) Volume Invert Avail.Storage Storage Description #1A 28.00' 0.146 of 52.00'W x 93.00'L x 6.00'H Field A 0.666 of Overall - 0.300 of Embedded = 0.366 of x 40.0% Voids #2A 28.50' 0.300 of CMP_Round 60 x 7 Inside #1 Effective Size= 60.0"W x 60.0"H => 19.59 sf x 20.00'L = 391.8 cf Overall Size= 60.0"W x 60.0"H x 20.001 Row Length Adjustment= +61.00' x 19.59 sf x 7 rows 50.00' Header x 19.59 sf x 2 = 1,959.0 cf 0.446 of Total Available Storage Storage Group A created with Chamber Wizard Device Routinq Invert Outlet Devices #1 Discarded 28.00' 2.410 in/hr Exfiltration over Surface area Conductivity to Groundwater Elevation = 0.00' #2 Primary 33.00' 18.0" Round Culvert L= 49.0' CPP, projecting, no headwall, Ke= 0.900 Inlet/ Outlet Invert= 33.00' / 32.75' S= 0.0051 T Cc= 0.900 n= 0.013 Corrugated PE, smooth interior, Flow Area= 1.77 sf Discarded OutFlow Max=0.33 cfs @ 12.46 hrs HW=34.00' (Free Discharge) L1=Exfi1tration ( Controls 0.33 cfs) Primary OutFlow Max=3.00 cfs @ 12.46 hrs HW=34.00' (Free Discharge) L2=Culvert (Barrel Controls 3.00 cfs @ 3.39 fps) Proposed Conditions_Resub. 2015-03-27 Type 111 24-hr 100-Year Rainfall=8.90" Prepared by {enter your company name here) Printed 3/26/2015 HydroCADO 10.00 s/n 04881 ©2011 HydroCAD Software Solutions LLC Paqe 84 Pond SSI-1: Subsurface Infiltration Basin 1-East - Chamber Wizard Field A Chamber Model = CMP_Round 60 Effective Size= 60.0"W x 60.0"H => 19.59 sf x 20.001 = 391.8 cf Overall Size= 60.0"W x 60.0"H x 20.001 Row Length Adjustment= +61.00' x 19.59 sf x 7 rows 60.0" Wide + 30.0" Spacing = 90.0" C-C Row Spacing 1 Chambers/Row x 20.00' Long +61.00' Row Adjustment +5.00' Header x 2 = 91.00' Row Length +12.0" End Stone x 2 = 93.00' Base Length 7 Rows x 60.0" Wide + 30.0" Spacing x 6 + 12.0" Side Stone x 2 = 52.00' Base Width 6.0" Base + 60.0" Chamber Height + 6.0" Cover = 6.00' Field Height 7 Chambers x 391.8 cf +61.00' Row Adjustment x 19.59 sf x 7 Rows + 50.00' Header x 19.59 sf x 2 = 13,066.5 cf Chamber Storage 29,016.0 cf Field - 13,066.5 cf Chambers = 15,949.5 cf Stone x 40.0% Voids = 6,379.8 cf Stone Storage Stone + Chamber Storage = 19,446.3 cf= 0.446 of Overall Storage Efficiency = 67.0% 7 Chambers 1,074.7 cy Field 590.7 cy Stone Proposed Conditions_Resub. 2015-03-27 Type 111 24-hr 100-Year Rainfall=8.90" Prepared by {enter your company name here) Printed 3/26/2015 HydroCAD® 10.00 s/n 04881 ©2011 HydroCAD Software Solutions LLC Paqe 85 Pond SSI-1: Subsurface Infiltration Basin 1-East Hydrograph Z 12.69 cfs ❑ inflow �—I 4- 1 El Discarded 14Outflow ❑Primary 13� / P6ak EUv:�344_10W_ 5:�/ / � 3.34 cfs 4� / / 3.02 cfs 0 fs' 1 0 �.�...(....,.. 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 Time (hours) Proposed Conditions_Resub. 2015-03-27 Type/1/ 24-hr 100-Year Rainfall=8.90" Prepared by {enter your company name here) Printed 3/26/2015 HydroCAD® 10.00 s/n 04881 ©2011 HydroCAD Software Solutions LLC Page 86 Summary for Pond SSI-2: Subsurface Infiltration Basin 2-South [79] Warning: Submerged Pond SWALE Primary device # 3 INLET by 1.45' Inflow Area = 5.691 ac, 79.53% Impervious, Inflow Depth > 6.33" for 100-Year event Inflow = 38.05 cfs @ 12.09 hrs, Volume= 3.002 of Outflow = 8.23 cfs @ 12.52 hrs, Volume= 2.330 af, Atten= 78%, Lag= 26.1 min Discarded = 1.42 cfs @ 12.52 hrs, Volume= 1.875 of Primary = 6.81 cfs @ 12.52 hrs, Volume= 0.455 of Routing by Stor-Ind method, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs Peak Elev= 33.96' @ 12.52 hrs Surf.Area= 0.517 ac Storage= 1.305 of Plug-Flow detention time= 216.1 min calculated for 2.330 of(78% of inflow) Center-of-Mass det. time= 136.7 min ( 909.0 - 772.3 ) Volume Invert Avail.Storage Storage Description #1A 30.00' 0.502 of 126.50'W x 178.00'L x 4.00'H Field A 2.068 of Overall - 0.811 of Embedded = 1.256 of x 40.0% Voids #2A 30.50' 0.811 of CMP_Round 36 x 28 Inside #1 Effective Size= 36.0"W x 36.0"H => 7.06 sf x 20.00'L = 141.1 cf Overall Size= 36.0"W x 36.0"H x 20.001 Row Length Adjustment= +150.00' x 7.06 sf x 28 rows 124.50' Header x 7.06 sf x 2 = 1,757.1 cf 1.314 of Total Available Storage Storage Group A created with Chamber Wizard Device Routinq Invert Outlet Devices #1 Discarded 30.00' 2.410 in/hr Exfiltration over Surface area Conductivity to Groundwater Elevation = 0.00' #2 Primary 30.50' 15.0" Round Culvert L= 29.0' CPP, projecting, no headwall, Ke= 0.900 Inlet/ Outlet Invert= 30.50' /30.20' S= 0.0103 '/' Cc= 0.900 n= 0.013 Corrugated PE, smooth interior, Flow Area= 1.23 sf #3 Device 2 33.40' 5.0' long Sharp-Crested Rectangular Weir 2 End Contraction(s) 2.9' Crest Height Discarded OutFlow Max=1.42 cfs @ 12.52 hrs HW=33.95' (Free Discharge) L1=Exfiltration ( Controls 1.42 cfs) Primary OutFlow Max=6.71 cfs @ 12.52 hrs HW=33.95' (Free Discharge) L2=Culvert (Passes 6.71 cfs of 7.84 cfs potential flow) L3=Sharp-Crested Rectangular Weir(Weir Controls 6.71 cfs @ 2.49 fps) Proposed Conditions_Resub. 2015-03-27 Type 111 24-hr 100-Year Rainfall=8.90" Prepared by {enter your company name here) Printed 3/26/2015 HydroCADO 10.00 s/n 04881 ©2011 HydroCAD Software Solutions LLC Paqe 87 Pond SSI-2: Subsurface Infiltration Basin 2-South - Chamber Wizard Field A Chamber Model = CMP_Round 36 Effective Size= 36.0"W x 36.0"H => 7.06 sf x 20.00'L = 141.1 cf Overall Size= 36.0"W x 36.0"H x 20.001 Row Length Adjustment= +150.00' x 7.06 sf x 28 rows 36.0" Wide + 18.0" Spacing = 54.0" C-C Row Spacing 1 Chambers/Row x 20.00' Long +150.00' Row Adjustment +3.00' Header x 2 = 176.00' Row Length +12.0" End Stone x 2 = 178.00' Base Length 28 Rows x 36.0" Wide + 18.0" Spacing x 27 + 12.0" Side Stone x 2 = 126.50' Base Width 6.0" Base + 36.0" Chamber Height + 6.0" Cover = 4.00' Field Height 28 Chambers x 141.1 cf +150.00' Row Adjustment x 7.06 sf x 28 Rows + 124.50' Header x 7.06 sf x 2 = 35,346.8 cf Chamber Storage 90,068.0 cf Field - 35,346.8 cf Chambers = 54,721.2 cf Stone x 40.0% Voids = 21,888.5 cf Stone Storage Stone + Chamber Storage = 57,235.3 cf= 1.314 of Overall Storage Efficiency = 63.5% 28 Chambers 3,335.9 cy Field 2,026.7 cy Stone Proposed Conditions_Resub. 2015-03-27 Type 111 24-hr 100-Year Rainfall=8.90" Prepared by {enter your company name here) Printed 3/26/2015 HydroCAD® 10.00 s/n 04881 ©2011 HydroCAD Software Solutions LLC Page 88 Pond SSI-2: Subsurface Infiltration Basin 2-South Hydrograph L I 1 ❑ Inflow �+� 38.05 cfs �� � � � � � ❑Dstca ded 42-� J.V �� ❑Primary 38� i eaA eWv�3"6t I I rt r-I rt 1 fi 1 -1 1- 3436 / j� tt� g�$'�3�5 a 4 �1 4- 1 4- 1 '.^� / 32 / 30 + + ++ - - - - - - —128� / 22: / j 020: / rt l_I fil I fi l films 16_/ / 1 8.23 cfs 10;/ / ' i i 6.81 cfs 6-�-/ / 1 fs 4- 2=' iii�ii�iiiiiiiiiiiiii, r�rrr����,����� 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 Time (hours) Proposed Conditions_Resub. 2015-03-27 Type/1/ 24-hr 100-Year Rainfall=8.90" Prepared by {enter your company name here) Printed 3/26/2015 HydroCAD® 10.00 s/n 04881 ©2011 HydroCAD Software Solutions LLC Page 89 Summary for Pond SSI-3: Subsurface Infiltration Basin 3-Southwest Inflow Area = 0.608 ac, 94.30% Impervious, Inflow Depth > 8.29" for 100-Year event Inflow = 5.14 cfs @ 12.09 hrs, Volume= 0.420 of Outflow = 1.36 cfs @ 12.45 hrs, Volume= 0.419 af, Atten= 73%, Lag= 22.1 min Discarded = 0.29 cfs @ 12.45 hrs, Volume= 0.383 of Primary = 1.07 cfs @ 12.45 hrs, Volume= 0.036 of Routing by Stor-Ind method, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs Peak Elev= 32.46' @ 12.45 hrs Surf.Area= 4,830 sf Storage= 6,748 cf Plug-Flow detention time= 168.2 min calculated for 0.418 of(99% of inflow) Center-of-Mass det. time= 165.8 min ( 920.2 - 754.4 ) Volume Invert Avail.Storage Storage Description #1A 30.00' 3,502 cf 46.00'W x 105.00'L x 2.50'H Field A 12,075 cf Overall - 3,320 cf Embedded = 8,755 cf x 40.0% Voids #2A 30.50' 3,320 cf CMP_Round 18 x 18 Inside #1 Effective Size= 18.0"W x 18.0"H => 1.76 sf x 20.00'L = 35.2 cf Overall Size= 18.0"W x 18.0"H x 20.001 Row Length Adjustment= +80.00' x 1.76 sf x 18 rows 44.00' Header x 1.76 sf x 2 = 154.7 cf 6,822 cf Total Available Storage Storage Group A created with Chamber Wizard Device Routinq Invert Outlet Devices #1 Discarded 30.00' 2.410 in/hr Exfiltration over Surface area Conductivity to Groundwater Elevation = 0.00' #2 Primary 30.00' 12.0" Round Culvert L= 100.0' CPP, projecting, no headwall, Ke= 0.900 Inlet/Outlet Invert= 30.00' / 29.00' S= 0.0100 '/' Cc= 0.900 n= 0.013 Corrugated PE, smooth interior, Flow Area= 0.79 sf #3 Device 2 32.30' 5.0' long Sharp-Crested Rectangular Weir 2 End Contraction(s) 1.8' Crest Height Discarded OutFlow Max=0.29 cfs @ 12.45 hrs HW=32.46' (Free Discharge) L1=Exfiltration ( Controls 0.29 cfs) Primary OutFlow Max=1.06 cfs @ 12.45 hrs HW=32.46' (Free Discharge) L2=Culvert (Passes 1.06 cfs of 4.18 cfs potential flow) L3=Sharp-Crested Rectangular Weir(Weir Controls 1.06 cfs @ 1.33 fps) Proposed Conditions_Resub. 2015-03-27 Type 111 24-hr 100-Year Rainfall=8.90" Prepared by {enter your company name here) Printed 3/26/2015 HydroCADO 10.00 s/n 04881 ©2011 HydroCAD Software Solutions LLC Paqe 90 Pond SSI-3: Subsurface Infiltration Basin 3-Southwest - Chamber Wizard Field A Chamber Model = CMP_Round 18 Effective Size= 18.0"W x 18.0"H => 1.76 sf x 20.00'L = 35.2 cf Overall Size= 18.0"W x 18.0"H x 20.001 Row Length Adjustment= +80.00' x 1.76 sf x 18 rows 18.0" Wide + 12.0" Spacing = 30.0" C-C Row Spacing 1 Chambers/Row x 20.00' Long +80.00' Row Adjustment +1.50' Header x 2 = 103.00' Row Length +12.0" End Stone x 2 = 105.00' Base Length 18 Rows x 18.0" Wide + 12.0" Spacing x 17 + 12.0" Side Stone x 2 = 46.00' Base Width 6.0" Base + 18.0" Chamber Height + 6.0" Cover = 2.50' Field Height 18 Chambers x 35.2 cf +80.00' Row Adjustment x 1.76 sf x 18 Rows + 44.00' Header x 1.76 sf x 2 = 3,319.7 cf Chamber Storage 12,075.0 cf Field - 3,319.7 cf Chambers = 8,755.3 cf Stone x 40.0% Voids = 3,502.1 cf Stone Storage Stone + Chamber Storage = 6,821.8 cf= 0.157 of Overall Storage Efficiency = 56.5% 18 Chambers 447.2 cy Field 324.3 cy Stone Proposed Conditions_Resub. 2015-03-27 Type/1/ 24-hr 100-Year Rainfall=8.90" Prepared by {enter your company name here) Printed 3/26/2015 HydroCAD® 10.00 s/n 04881 ©2011 HydroCAD Software Solutions LLC Page 91 Pond SSI-3: Subsurface Infiltration Basin 3-Southwest Hydrograph 5.14 cfs El Inflow ❑Outflow Inflow Area=0.60 a El P❑P rimrimararyy ded Peak Elev=32.46' 5 Storage=6,748 cf 4 I� fill I � � Irt ° - IIIIIIIII IIIIIIII ' LL - 2� 1.36 cfs 1.07 cfs 1= ,, 0 cfsgj/x i 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 Time (hours) Proposed Conditions_Resub. 2015-03-27 Type/1/ 24-hr 100-Year Rainfall=8.90" Prepared by {enter your company name here) Printed 3/26/2015 HydroCAD® 10.00 s/n 04881 ©2011 HydroCAD Software Solutions LLC Page 92 Summary for Pond SWALE: Water Quality Swale [79] Warning: Submerged Pond SED Primary device # 2 by 1.13' Inflow Area = 1.038 ac, 49.25% Impervious, Inflow Depth > 3.13" for 100-Year event Inflow = 4.46 cfs @ 12.11 hrs, Volume= 0.271 of Outflow = 1.56 cfs @ 12.47 hrs, Volume= 0.271 af, Atten= 65%, Lag= 21.2 min Discarded = 0.80 cfs @ 12.47 hrs, Volume= 0.250 of Primary = 0.77 cfs @ 12.47 hrs, Volume= 0.021 of Routing by Stor-Ind method, Time Span= 0.00-24.00 hrs, dt= 0.05 hrs Peak Elev= 36.13' @ 12.47 hrs Surf.Area= 4,020 sf Storage= 5,167 cf Plug-Flow detention time= 57.7 min calculated for 0.271 of(100% of inflow) Center-of-Mass det. time= 57.5 min ( 856.4 - 798.9 ) Volume Invert Avail.Storage Storage Description #1 34.00' 9,132 cf Custom Stage Data (Prismatic)Listed below (Recalc) Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) 34.00 5 0 0 35.00 2,730 1,368 1,368 36.00 3,868 3,299 4,667 37.00 5,063 4,466 9,132 Device Routinq Invert Outlet Devices #1 Discarded 34.00' 8.270 in/hr Exfiltration over Surface area Conductivity to Groundwater Elevation = 0.00' #2 Device 3 35.95' 12.0" Horiz. Orifice/Grate C= 0.600 Limited to weir flow at low heads #3 Primary 32.50' 15.0" Round Culvert L= 67.0' CPP, projecting, no headwall, Ke= 0.900 Inlet/ Outlet Invert= 32.50' /31.70' S= 0.0119 T Cc= 0.900 n= 0.013 Corrugated PE, smooth interior, Flow Area= 1.23 sf Discarded OutFlow Max=0.80 cfs @ 12.47 hrs HW=36.13' (Free Discharge) L1=Exfiltration ( Controls 0.80 cfs) Primary OutFlow Max=0.75 cfs @ 12.47 hrs HW=36.13' (Free Discharge) L Culvert (Passes 0.75 cfs of 8.08 cfs potential flow) 2=Orifice/Grate (Weir Controls 0.75 cfs @ 1.37 fps) Proposed Conditions_Resub. 2015-03-27 Type 111 24-hr 100-Year Rainfall=8.90" Prepared by {enter your company name here) Printed 3/26/2015 HydroCADO 10.00 s/n 04881 ©2011 HydroCAD Software Solutions LLC Paqe 93 Pond SWALE: Water Quality Swale Hydrograph M Inflow �nl�w1��-e��1.10814.46 cfs I� N�stcarded ■Primary _ Nak 8I6v:�316.131 - � IIIIIIIIIII 1.56�cfs = � I IIIIIII I III � II 1 0.77 cfs 0 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 Time (hours) IV. MASSACHUSETTS STORMWATER REPORT CHECKLIST Massachusetts Department of Environmental Protection Bureau of Resource Protection - Wetlands Program Checklist for Stormwater Report A. Introduction Important:When A Stormwater Report must be submitted with the Notice of Intent permit application to document filling out forms compliance with the Stormwater Management Standards. The following checklist is NOT a substitute for on the computer, should h h hi t R t St e Stormwater Report (which sou provide more substantive and detailed information use only the tab the p ( p ) but is offered key to move your here as a tool to help the applicant organize their Stormwater Management documentation for their cursor-do not Report and for the reviewer to assess this information in a consistent format. As noted in the Checklist, use the return the Stormwater Report must contain the engineering computations and supporting information set forth in key. Volume 3 of the Massachusetts Stormwater Handbook. The Stormwater Report must be prepared and certified by a Registered Professional Engineer(RPE) licensed in the Commonwealth. The Stormwater Report must include: • The Stormwater Checklist completed and stamped by a Registered Professional Engineer(see page 2)that certifies that the Stormwater Report contains all required submittals.' This Checklist is to be used as the cover for the completed Stormwater Report. • Applicant/Project Name • Project Address • Name of Firm and Registered Professional Engineer that prepared the Report • Long-Term Pollution Prevention Plan required by Standards 4-6 • Construction Period Pollution Prevention and Erosion and Sedimentation Control Plan required by Standard 82 • Operation and Maintenance Plan required by Standard 9 In addition to all plans and supporting information, the Stormwater Report must include a brief narrative describing stormwater management practices, including environmentally sensitive site design and LID techniques, along with a diagram depicting runoff through the proposed BMP treatment train. Plans are required to show existing and proposed conditions, identify all wetland resource areas, NRCS soil types, critical areas, Land Uses with Higher Potential Pollutant Loads (LUHPPL), and any areas on the site where infiltration rate is greater than 2.4 inches per hour. The Plans shall identify the drainage areas for both existing and proposed conditions at a scale that enables verification of supporting calculations. As noted in the Checklist, the Stormwater Management Report shall document compliance with each of the Stormwater Management Standards as provided in the Massachusetts Stormwater Handbook. The soils evaluation and calculations shall be done using the methodologies set forth in Volume 3 of the Massachusetts Stormwater Handbook. To ensure that the Stormwater Report is complete, applicants are required to fill in the Stormwater Report Checklist by checking the box to indicate that the specified information has been included in the Stormwater Report. If any of the information specified in the checklist has not been submitted, the applicant must provide an explanation. The completed Stormwater Report Checklist and Certification must be submitted with the Stormwater Report. The Stormwater Report may also include the Illicit Discharge Compliance Statement required by Standard 10. If not included in the Stormwater Report,the Illicit Discharge Compliance Statement must be submitted prior to the discharge of stormwater runoff to the post-construction best management practices. 2 For some complex projects,it may not be possible to include the Construction Period Erosion and Sedimentation Control Plan in the Stormwater Report. In that event,the issuing authority has the discretion to issue an Order of Conditions that approves the project and includes a condition requiring the proponent to submit the Construction Period Erosion and Sedimentation Control Plan before commencing any land disturbance activity on the site. Stormwater Checklist.doc•04/01/08 Stormwater Report Checklist•Page 1 of 8 LlMassachusetts Department of Environmental Protection Bureau of Resource Protection - Wetlands Program Checklist for Stormwater Report B. Stormwater Checklist and Certification The following checklist is intended to serve as a guide for applicants as to the elements that ordinarily need to be addressed in a complete Stormwater Report. The checklist is also intended to provide conservation commissions and other reviewing authorities with a summary of the components necessary for a comprehensive Stormwater Report that addresses the ten Stormwater Standards. Note: Because stormwater requirements vary from project to project, it is possible that a complete Stormwater Report may not include information on some of the subjects specified in the Checklist. If it is determined that a specific item does not apply to the project under review, please note that the item is not applicable (N.A.) and provide the reasons for that determination. A complete checklist must include the Certification set forth below signed by the Registered Professional Engineer who prepared the Stormwater Report. Registered Professional Engineer's Certification I have reviewed the Stormwater Report, including the soil evaluation, computations, Long-term Pollution Prevention Plan, the Construction Period Erosion and Sedimentation Control Plan (if included), the Long- term Post-Construction Operation and Maintenance Plan, the Illicit Discharge Compliance Statement(if included) and the plans showing the stormwater management system, and have determined that they have been prepared in accordance with the requirements of the Stormwater Management Standards as further elaborated by the Massachusetts Stormwater Handbook. I have also determined that the information presented in the Stormwater Checklist is accurate and that the information presented in the Stormwater Report accurately reflects conditions at the site as of the date of this permit application. Registered Professional Engineer Block and Signature 4j0 9 o JOHN J. MY CIVIL ca No,42797 2 -16 --� Si 6at #,� ate Checklist Project Type: Is the application for new development, redevelopment, or a mix of new and redevelopment? ❑ New development ® Redevelopment ❑ Mix of New Development and Redevelopment Stormwater Checklist•04/01/08 Stormwater Report Checklist•Page 2 of 8 Massachusetts Department of Environmental Protection Bureau of Resource Protection - Wetlands Program Checklist for Stormwater Report Checklist (continued) LID Measures: Stormwater Standards require LID measures to be considered. Document what environmentally sensitive design and LID Techniques were considered during the planning and design of the project: ® No disturbance to any Wetland Resource Areas ❑ Site Design Practices (e.g. clustered development, reduced frontage setbacks) ® Reduced Impervious Area (Redevelopment Only) ❑ Minimizing disturbance to existing trees and shrubs ❑ LID Site Design Credit Requested: ❑ Credit 1 ❑ Credit 2 ❑ Credit 3 ❑ Use of"country drainage" versus curb and gutter conveyance and pipe ❑ Bioretention Cells (includes Rain Gardens) ❑ Constructed Stormwater Wetlands (includes Gravel Wetlands designs) ® Treebox Filter ® Water Quality Swale ❑ Grass Channel ❑ Green Roof ❑ Other(describe): Standard 1: No New Untreated Discharges ® No new untreated discharges ® Outlets have been designed so there is no erosion or scour to wetlands and waters of the Commonwealth ❑ Supporting calculations specified in Volume 3 of the Massachusetts Stormwater Handbook included. Stormwater Checklist.doc•04/01/08 Stormwater Report Checklist•Page 3 of 8 Massachusetts Department of Environmental Protection Bureau of Resource Protection - Wetlands Program Checklist for Stormwater Report Checklist (continued) Standard 2: Peak Rate Attenuation ❑ Standard 2 waiver requested because the project is located in land subject to coastal storm flowage and stormwater discharge is to a wetland subject to coastal flooding. ❑ Evaluation provided to determine whether off-site flooding increases during the 100-year 24-hour storm. ® Calculations provided to show that post-development peak discharge rates do not exceed pre- development rates for the 2-year and 10-year 24-hour storms. If evaluation shows that off-site flooding increases during the 100-year 24-hour storm, calculations are also provided to show that post-development peak discharge rates do not exceed pre-development rates for the 100-year 24- hour storm. Standard 3: Recharge ❑ Soil Analysis provided. ❑ Required Recharge Volume calculation provided. ❑ Required Recharge volume reduced through use of the LID site Design Credits. ® Sizing the infiltration, BMPs is based on the following method: Check the method used. ® Static ❑ Simple Dynamic ❑ Dynamic Field' ❑ Runoff from all impervious areas at the site discharging to the infiltration BMP. ❑ Runoff from all impervious areas at the site is not discharging to the infiltration BMP and calculations are provided showing that the drainage area contributing runoff to the infiltration BMPs is sufficient to generate the required recharge volume. ® Recharge BMPs have been sized to infiltrate the Required Recharge Volume. ❑ Recharge BMPs have been sized to infiltrate the Required Recharge Volume only to the maximum extent practicable for the following reason: ❑ Site is comprised solely of C and D soils and/or bedrock at the land surface ❑ M.G.L. c. 21 E sites pursuant to 310 CMR 40.0000 ❑ Solid Waste Landfill pursuant to 310 CMR 19.000 ❑ Project is otherwise subject to Stormwater Management Standards only to the maximum extent practicable. ❑ Calculations showing that the infiltration BMPs will drain in 72 hours are provided. ❑ Property includes a M.G.L. c. 21 E site or a solid waste landfill and a mounding analysis is included. 80%TSS removal is required prior to discharge to infiltration BMP if Dynamic Field method is used. Stormwater Checklist.doc•04/01/08 Stormwater Report Checklist•Page 4 of 8 Massachusetts Department of Environmental Protection Bureau of Resource Protection - Wetlands Program Checklist for Stormwater Report Checklist (continued) Standard 3: Recharge (continued) ❑ The infiltration BMP is used to attenuate peak flows during storms greater than or equal to the 10- year 24-hour storm and separation to seasonal high groundwater is less than 4 feet and a mounding analysis is provided. ❑ Documentation is provided showing that infiltration BMPs do not adversely impact nearby wetland resource areas. Standard 4: Water Quality The Long-Term Pollution Prevention Plan typically includes the following: • Good housekeeping practices; • Provisions for storing materials and waste products inside or under cover; • Vehicle washing controls; • Requirements for routine inspections and maintenance of stormwater BMPs; • Spill prevention and response plans; • Provisions for maintenance of lawns, gardens, and other landscaped areas; • Requirements for storage and use of fertilizers, herbicides, and pesticides; • Pet waste management provisions; • Provisions for operation and management of septic systems; • Provisions for solid waste management; • Snow disposal and plowing plans relative to Wetland Resource Areas; • Winter Road Salt and/or Sand Use and Storage restrictions; • Street sweeping schedules; • Provisions for prevention of illicit discharges to the stormwater management system; • Documentation that Stormwater BMPs are designed to provide for shutdown and containment in the event of a spill or discharges to or near critical areas or from LUHPPL; • Training for staff or personnel involved with implementing Long-Term Pollution Prevention Plan; • List of Emergency contacts for implementing Long-Term Pollution Prevention Plan. ® A Long-Term Pollution Prevention Plan is attached to Stormwater Report and is included as an attachment to the Wetlands Notice of Intent. ❑ Treatment BMPs subject to the 44% TSS removal pretreatment requirement and the one inch rule for calculating the water quality volume are included, and discharge: ❑ is within the Zone II or Interim Wellhead Protection Area ❑ is near or to other critical areas ❑ is within soils with a rapid infiltration rate (greater than 2.4 inches per hour) ❑ involves runoff from land uses with higher potential pollutant loads. ❑ The Required Water Quality Volume is reduced through use of the LID site Design Credits. ® Calculations documenting that the treatment train meets the 80% TSS removal requirement and, if applicable, the 44% TSS removal pretreatment requirement, are provided. Stormwater Checklist.doc•04/01/08 Stormwater Report Checklist•Page 5 of 8 Massachusetts Department of Environmental Protection Bureau of Resource Protection - Wetlands Program Checklist for Stormwater Report Checklist (continued) Standard 4: Water Quality(continued) ❑ The BMP is sized (and calculations provided) based on: ® The '/2"or 1"Water Quality Volume or ❑ The equivalent flow rate associated with the Water Quality Volume and documentation is provided showing that the BMP treats the required water quality volume. ❑ The applicant proposes to use proprietary BMPs, and documentation supporting use of proprietary BMP and proposed TSS removal rate is provided. This documentation may be in the form of the propriety BMP checklist found in Volume 2, Chapter 4 of the Massachusetts Stormwater Handbook and submitting copies of the TARP Report, STEP Report, and/or other third party studies verifying performance of the proprietary BMPs. ❑ A TMDL exists that indicates a need to reduce pollutants other than TSS and documentation showing that the BMPs selected are consistent with the TMDL is provided. Standard 5: Land Uses With Higher Potential Pollutant Loads (LUHPPLs) ❑ The NPDES Multi-Sector General Permit covers the land use and the Stormwater Pollution Prevention Plan (SWPPP) has been included with the Stormwater Report. ❑ The NPDES Multi-Sector General Permit covers the land use and the SWPPP will be submitted prior to the discharge of stormwater to the post-construction stormwater BMPs. ® The NPDES Multi-Sector General Permit does not cover the land use. ❑ LUHPPLs are located at the site and industry specific source control and pollution prevention measures have been proposed to reduce or eliminate the exposure of LUHPPLs to rain, snow, snow melt and runoff, and been included in the long term Pollution Prevention Plan. ❑ All exposure has been eliminated. ® All exposure has not been eliminated and all BMPs selected are on MassDEP LUHPPL list. ® The LUHPPL has the potential to generate runoff with moderate to higher concentrations of oil and grease (e.g. all parking lots with >1000 vehicle trips per day)and the treatment train includes an oil grit separator, a filtering bioretention area, a sand filter or equivalent. Standard 6: Critical Areas ❑ The discharge is near or to a critical area and the treatment train includes only BMPs that MassDEP has approved for stormwater discharges to or near that particular class of critical area. ❑ Critical areas and BMPs are identified in the Stormwater Report. Stormwater Checklist.doc•04/01/08 Stormwater Report Checklist•Page 6 of 8 Massachusetts Department of Environmental Protection Bureau of Resource Protection - Wetlands Program Checklist for Stormwater Report Checklist (continued) Standard 7: Redevelopments and Other Projects Subject to the Standards only to the maximum extent practicable ® The project is subject to the Stormwater Management Standards only to the maximum Extent Practicable as a: ❑ Limited Project ❑ Small Residential Projects: 5-9 single family houses or 5-9 units in a multi-family development provided there is no discharge that may potentially affect a critical area. ❑ Small Residential Projects: 2-4 single family houses or 2-4 units in a multi-family development with a discharge to a critical area ❑ Marina and/or boatyard provided the hull painting, service and maintenance areas are protected from exposure to rain, snow, snow melt and runoff ❑ Bike Path and/or Foot Path ® Redevelopment Project ❑ Redevelopment portion of mix of new and redevelopment. ❑ Certain standards are not fully met(Standard No. 1, 8, 9, and 10 must always be fully met)and an explanation of why these standards are not met is contained in the Stormwater Report. ® The project involves redevelopment and a description of all measures that have been taken to improve existing conditions is provided in the Stormwater Report. The redevelopment checklist found in Volume 2 Chapter 3 of the Massachusetts Stormwater Handbook may be used to document that the proposed stormwater management system (a) complies with Standards 2, 3 and the pretreatment and structural BMP requirements of Standards 4-6 to the maximum extent practicable and (b) improves existing conditions. Standard 8: Construction Period Pollution Prevention and Erosion and Sedimentation Control A Construction Period Pollution Prevention and Erosion and Sedimentation Control Plan must include the following information: • Narrative; • Construction Period Operation and Maintenance Plan; • Names of Persons or Entity Responsible for Plan Compliance; • Construction Period Pollution Prevention Measures; • Erosion and Sedimentation Control Plan Drawings; • Detail drawings and specifications for erosion control BMPs, including sizing calculations; • Vegetation Planning; • Site Development Plan; • Construction Sequencing Plan; • Sequencing of Erosion and Sedimentation Controls; • Operation and Maintenance of Erosion and Sedimentation Controls; • Inspection Schedule; • Maintenance Schedule; Inspection and Maintenance Log Form. ® A Construction Period Pollution Prevention and Erosion and Sedimentation Control Plan containing the information set forth above has been included in the Stormwater Report. Stormwater Checklist.doc•04/01/08 Stormwater Report Checklist•Page 7 of 8 Massachusetts Department of Environmental Protection Bureau of Resource Protection - Wetlands Program Checklist for Stormwater Report Checklist (continued) Standard 8: Construction Period Pollution Prevention and Erosion and Sedimentation Control (continued) ❑ The project is highly complex and information is included in the Stormwater Report that explains why it is not possible to submit the Construction Period Pollution Prevention and Erosion and Sedimentation Control Plan with the application. A Construction Period Pollution Prevention and Erosion and Sedimentation Control has not been included in the Stormwater Report but will be submitted before land disturbance begins. ® The project is not covered by a NPDES Construction General Permit. ❑ The project is covered by a NPDES Construction General Permit and a copy of the SWPPP is in the Stormwater Report. ❑ The project is covered by a NPDES Construction General Permit but no SWPPP been submitted. The SWPPP will be submitted BEFORE land disturbance begins. Standard 9: Operation and Maintenance Plan ® The Post Construction Operation and Maintenance Plan is included in the Stormwater Report and includes the following information: ® Name of the stormwater management system owners; ® Party responsible for operation and maintenance; ® Schedule for implementation of routine and non-routine maintenance tasks; ® Plan showing the location of all stormwater BMPs maintenance access areas; ® Description and delineation of public safety features; ❑ Estimated operation and maintenance budget; and ® Operation and Maintenance Log Form. ❑ The responsible party is not the owner of the parcel where the BMP is located and the Stormwater Report includes the following submissions: ❑ A copy of the legal instrument(deed, homeowner's association, utility trust or other legal entity) that establishes the terms of and legal responsibility for the operation and maintenance of the project site stormwater BMPs; ❑ A plan and easement deed that allows site access for the legal entity to operate and maintain BMP functions. Standard 10: Prohibition of Illicit Discharges ® The Long-Term Pollution Prevention Plan includes measures to prevent illicit discharges; ® An Illicit Discharge Compliance Statement is attached; ❑ NO Illicit Discharge Compliance Statement is attached but will be submitted prior to the discharge of any stormwater to post-construction BMPs. Stormwater Checklist.doc•04/01/08 Stormwater Report Checklist•Page 8 of 8 V. APPENDIX A Construction Period Pollution Prevention Plan (CPPPP) 480 Suite 3 Arsenal Street Watertown, Massachusetts Prepared for: Boylston Properties 800 Boylston Street Boston, MA 02199 Prepared by: R.J. O'Connell & Associates 80 Montvale Ave, Suite 201 Stoneham, MA 02180 Date: February 10, 2015 Construction Period Pollution Prevention Plan(CPPPP) 480 Suite 3 Arsenal Street- Watertown, MA Contents SECTION 1: SITE EVALUATION, ASSESSMENT,AND PLANNING..................................I 1.1 Project/Site Information...................................................................................................... 1 1.2 Contact Information/Responsible Parties ...........................................................................2 1.3 Nature and Sequence of Construction Activity ..................................................................2 1.4 Construction Site Estimates................................................................................................2 1.5 Potential Sources of Pollution.............................................................................................3 1.6 Endangered Species Certification.......................................................................................3 1.7 Historic Preservation...........................................................................................................3 1.8 Maps and Figures................................................................................................................3 SECTION 2: EROSION AND SEDIMENT CONTROL BMPS ................................................4 2.1 Minimize Disturbed Area and Protect Natural Features and Soil.......................................7 2.2 Phase Construction Activity ...............................................................................................7 2.3 Control Stormwater Flowing onto and through the Project................................................ 5 2.4 Stabilize Soils......................................................................................................................6 2.5 Protect Storm Drain Inlets ..................................................................................................6 2.6 Establish Perimeter Controls and Sediment Barriers.......................................................... 6 2.7 Retain Sediment On-Site.....................................................................................................7 2.8 Establish Stabilized Construction Exits..............................................................................7 SECTION 3: GOOD HOUSEKEEPING BMPS ..........................................................................8 3.1 Material Handling and Waste Management ....................................................................... 8 3.2 Establish Proper Building Material Staging Areas............................................................. 8 3.3 Designate Washout Areas................................................................................................... 8 3.4 Establish Proper Equipment/Vehicle Fueling and Maintenance Practices.........................9 3.5 Control Equipment/Vehicle Washing.................................................................................9 3.6 Spill Prevention and Control Plan.......................................................................................9 3.7 Any Additional BMPs ...................................................................................................... 10 3.8 Allowable Non-Stormwater Discharge Management....................................................... 10 SECTION 4: CONSTRUCTION PERIOD POLLUTION PREVENTION AND SEDIMENTATION PLAN FORMS AND LOGS..................................................... 11 4.1 Construction Site Inspection Report Form ........................................................................... 4.2 Corrective Action Log.......................................................................................................... 4.3 Amendment Log................................................................................................................... 4.4 Subcontractor Certifications/Agreements............................................................................ 4.5 Grading and Stabilization Activites Log............................................................................... 4.6 Training Log......................................................................................................................... 4.7 Delegation of Authority Form .............................................................................................. APPENDICES.................................................................................................................................... Appendix A-Figures Figure 1: USGS Locus Map Appendix B-Site Plans entitled"Site Plan 480 Suite 3 Arsenal Street, Watertown, MA" (Under Separate Cover) Construction Period Pollution Prevention Plan(CPPPP) 480 Suite 3 Arsenal Street- Watertown, MA SECTION 1: SITE EVALUATION, ASSESSMENT, AND PLANNING 1.1 Project/Site Information Project/Site Name: 480 Suite 3 Arsenal Street Project Street/Location: 480 Suite 3 Arsenal Street City: Watertown State: MA ZIP Code: 02472 County or Similar Subdivision: Middlesex Countv Latitude/Longitude (Use one of three possible formats, and specify method) Latitude: Longitude: 1. 42 °22' 0 F N (degrees, minutes, seconds) 1. 71 ° 09' 27"W(degrees, minutes, seconds) 2. __°__. __' N (degrees, minutes, decimal) 2. __°__. __' W(degrees, minutes, decimal) 3. ____°N (decimal) 3. . ____'W(decimal) Method for determining latitude/longitude: ❑ USGS topographic map (specify scale: 1 ❑ EPA Web site ❑ GPS ® Other(please specify): Goode Earth Is the project located in Indian country? ❑ Yes ® No If yes, name of Reservation, or if not part of a Reservation, indicate "not applicable." Is this project considered a federal facility? ❑ Yes ® No NPDES project or permit tracking number*: _TBD *(This is the unique identifying number assigned to your project by your permitting authority after you have applied for coverage under the appropriate National Pollutant Discharge Elimination System (NPDES)construction general permit.) Page 1 Construction Period Pollution Prevention Plan(CPPPP) 480 Suite 3 Arsenal Street- Watertown, MA 1.2 Contact Information/Responsible Parties Operator: Boylston Properties 800 Boylston Street Boston, MA 02199 Phone: 617-262-4646 This Plan was Prepared by: R.J. O'Connell &Associates, Inc. John Stoy 80 Montvale Avenue— Suite 201 Stoneham, MA 02180 Phone: 781-279-0180 ext. 123 Email:john.stoy@rjoconnell.com 1.3 Nature and Sequence of Construction Activity General Scope: The proposed project is located on a±8.59 acre site located on Arsenal Street in Watertown, Massachusetts. Currently the site is occupied by a one story±74,400 square foot metal and concrete block warehouse. The proposed project includes a±185,595 sf office building and reworking the existing parking lot to provide 483 parking spaces at grade and an additional 83 spaces in a parking structure. What is the function of the construction activity? ❑ Residential ® Commercial ❑ Industrial ❑ Road Construction ❑ Linear Utility ❑ Other(please specify): Estimated Project Start Date: Fall 2015 Estimated Project Completion Date: Spring 2017 1.4 Construction Site Estimates Total site area: 8.59 acres Construction site area to be disturbed: 8.74 acres Percentage impervious area before construction: 81.7% Percentage impervious area after construction: 77.2% Page 2 Construction Period Pollution Prevention Plan(CPPPP) 480 Suite 3 Arsenal Street- Watertown, MA 1.5 Potential Sources of Pollution Potential Sources of Sediment to Stormwater Runoff: Potential sources of sediment that could affect the quality of stormwater discharges from the construction site include track-out sediment from trucks leaving the site, runoff from stockpiles containing sediment, and sediment from exposed ground surfaces resulting from earth-disturbing activities. Potential Pollutants and Sources Other Than Sediment to Stormwater: Potential pollutants and sources other than sediment to stormwater include litter, debris,runoff from vehicle washing operations that could be exposed to stormwater, and construction chemicals such as diesel fuel, hydraulic fluids and other petroleum products. 1.6 Endangered Species Certification Are endangered or threatened species and critical habitats on or near the project area? ❑ Yes ®No 1.7 Historic Preservation Are there any historic sites on or near the construction site? ❑ Yes ®No 1.8 Maps and Figures See Appendix A—Figures for Site Locus Plan. See Appendix B under separate cover for site development plans. Page 3 Construction Period Pollution Prevention Plan(CPPPP) 480 Suite 3 Arsenal Street- Watertown, MA SECTION 2: EROSION AND SEDIMENT CONTROL BMPS 2.1 Minimize Disturbed Area and Protect Natural Features and Soil Contractor staging areas, stockpile areas,refueling areas, concrete wash-out areas, etc. will be located outside of any 100- foot wetland buffer zones. 2.2 Erosion & Sediment Control During Construction Activities The following erosion and sediment control measures shall be implemented prior to and during construction or on as needed basis. • Prior to any construction activity, silt fencing and/or wattles shall be installed at the limits of the work area as shown on the plans. Erosion and sediment controls may be installed in stages,but must be in place prior to disturbance of soils within the area draining them. • Stabilized construction entrances shall be installed at the site entrances as shown on the drawings. The construction entrance locations shall be adjusted as necessary as construction proceeds. • Install sedimentation filter bags in all existing catch basins within the construction area until the structures are abandoned or the area has received permanent stabilization treatment. • Erosion controls must remain in place during demolition, and grading activities. Cuts and fills shall be performed in such a manner that runoff will continue to be directed toward erosion and sediment controls measures installed on-site. • The Contractor shall minimize the area of disturbed soil and efforts shall be made to limit the time of exposure of disturbed areas. • Erosion control measures shall be routinely inspected and cleaned,repaired or replaced as necessary. The Owner and/or Owner's representative will monitor the measures for proper maintenance and operation throughout the construction period. Documentation will be maintained and kept up-to-date by the Contractor on all inspections and repairs performed in accordance with the NPDES General Construction Permit and this Construction Pollution Prevention Plan requirements. Copies of all inspection reports must be kept on file at the on-site construction office. • Where construction activities have permanently ceased or have temporarily been suspended for more than seven days,or when final grades are reached in any portion of the site, stabilization practices shall be implemented within three days. Areas which remain disturbed but inactive for at least thirty days shall receive temporary seeding in accordance with the DEP Erosion and Sedimentation Control Guidelines,May 2003,the EPA Erosion and Sediment Control Inventory of Current Practices,April 1990 and all local municipal regulations. • Stockpiled soil shall be surrounded on their perimeters with wattles and/or siltation fences to prevent and/or control siltation and erosion. Tops of stockpiles shall be covered in such a manner that stormwater does not infiltrate the materials and thereby render the same unsuitable for fill use. Page 4 Construction Period Pollution Prevention Plan(CPPPP) 480 Suite 3 Arsenal Street- Watertown, MA • Any dewatering activities in which water will be released to a resource area as defined under M.G.L. Chapter 131 Section 40 or to a storm drain shall use a settling pond or similar device to remove sediment before water is released. • Haybale or wattle dikes shall be constructed at all existing&proposed catch basins located in areas subject to stormwater run-off from proposed fill areas during construction, or as directed by the Owner/Owner's Represenative.No sediments shall enter the on-site drainage system at any time. • Dust control shall be employed during site grading operations. Dust control methods shall consist of dampening the ground with water, or an emulsion soil stabilizer if water does not provide adequate dust control. Structural Practices: Structural practices which will be used on this site to divert stormwater runoff away from exposed soils, store stormwater runoff, and discharge stormwater from the site include but are not limited to the following; silt fences,wattles,drainage swales, sediment traps, check dams, catch basins, temporary sediment basins, outlet control structure,permanent seeding and landscaping treatments (including permanent mulches, as applicable), and structural surfaces such as pavements. The site work drawings show and detail the locations of these structural practices. 2.3 Control Stormwater Flowing onto and through the Project BMP Description: Temporary diversion ditches Installation Schedule: At commencement of earthwork activities and relocate as needed during earthwork activities Maintenance and Once weekly and within 24 hours of the end of a rainfall event Inspection: that is 0.25 inches or greater Responsible Staff. CPPPP Contact and/or their responsible designee BMP Description:Sedimentation filter bag Installation Schedule: At commencement of construction activities Maintenance and Once weekly and within 24 hours of the end of a rainfall event Inspection: that is 0.25 inches or greater. Sediment to be removed when bag is half full Responsible Staff. CPPPP Contact and/or their responsible designee BMP Description: Temporary Sedimentation Basin Installation Schedule: At commencement of earthwork activities Maintenance and Once every 7 calendar days. Sediment to be removed before it Inspection: reaches '/2 capacity of the sedimentation basin. Responsible Staff. CPPPP Contact and/or their responsible designee Page 5 Construction Period Pollution Prevention Plan(CPPPP) 480 Suite 3 Arsenal Street- Watertown, MA BMP Description: Catch Basins with 4 ft Sumps Installation Schedule: Upon completion of rough grading activities Maintenance and Once every 7 calendar days. Catch basins shall be cleaned when Inspection: sediment accumulates to within one (1) foot of the outlet invert. Responsible Staff CPPPP Contact and/or their responsible designee BMP Description: Oil/Grit Separator Installation Schedule: Upon completion of rough grading activities. Maintenance and Once every 7 calendar days. Particle separators shall be cleaned Inspection: when the stored volume reaches 15% of capacity. Responsible Staff: CPPPP Contact and/or their responsible designee 2.4 Stabilize Soils BMP Description:Mulch, hay or seeding for temporary vegetation of disturbed or exposed Areas Installation Schedule: As needed. No areas shall be left disturbed for longer than necessary to complete the work associated with that area Maintenance and Once weekly and within 24 hours of the end of a rainfall event Inspection: that is 0.25 inches or greater Responsible Staff. CPPPP Contact and/or their responsible designee 2.5 Protect Storm Drain Inlets BMP Description:Sedimentation filter bag Installation Schedule: At commencement of construction activities Maintenance and Once weekly and within 24 hours of the end of a rainfall event Inspection: that is 0.25 inches or greater. Sediment to be removed when bag is half full. Responsible Staff: CPPPP Contact and/or their responsible designee 2.6 Establish Perimeter Controls and Sediment Barriers BMP Description:Silt fence and/or wattle barrier Installation Schedule: Prior to any construction activity Maintenance and Once weekly and within 24 hours of the end of a rainfall event Inspection: that is 0.25 inches or greater. Responsible Staff CPPPP Contact and/or their responsible designee Page 6 Construction Period Pollution Prevention Plan(CPPPP) 480 Suite 3 Arsenal Street- Watertown, MA BMP Description: Temporar.Y sedimentation basin Installation Schedule: At commencement of construction activities Maintenance and Once weekly and within 24 hours of the end of a rainfall event Inspection: that is 0.25 inches or greater. Sediment to be removed when traps are half full with sediment Responsible Staff CPPPP Contact and/or their responsible designee 2.7 Retain Sediment On-Site BMP Description:Sedimentation filter bag Installation Schedule: At commencement of construction activities Maintenance and Inspect daily and within 24 hours of the end of a rainfall event Inspection: that is 0.25 inches or greater. Sediment bag to be removed and replaced when bag is half full. Responsible Staff CPPPP Contact and/or their responsible designee 2.8 Establish Stabilized Construction Exits BMP Description: Construction entrance vehicle tracing pads Installation Schedule: Prior to the commencement of any earthwork operations Maintenance and Once weekly and within 24 hours of the end of a rainfall event Inspection: that is 0.25 inches or greater. Replace crushed stone or remove sediment when voids are full. Responsible Staff CPPPP Contact and/or their responsible designee Page 7 Construction Period Pollution Prevention Plan(CPPPP) 480 Suite 3 Arsenal Street- Watertown, MA SECTION 3: GOOD HOUSEKEEPING BMPS 3.1 Material Handling and Waste Management BMP Description:Solid waste containers/dumpsters. Installation Schedule: At commencement of construction activities Maintenance and Trash to be picked up on a daily basis, dumpsters emptied when Inspection: full. Cover to be put on dumpster when full to prevent trash from blowing throughout site. Responsible Staff. CPPPP Contact and/or their responsible designee 3.2 Establish Proper Building Material Staging Areas BMP Description:Silt fences and haybales at all stockpile areas of construction and excavated material Installation Schedule: At the commencement of construction activities Maintenance and Once weekly and within 24 hours of the end of a rainfall event Inspection: that is 0.25 inches or greater Responsible Staff. CPPPP Contact and/or their responsible designee 3.3 Designate Washout Areas BMP Description:Equipment washing shall occur only within drainage areas with temporary sedimentation basins. Designated washout areas shall be flagged off and washing shall occur only in these areas. Areas shall be contained to prevent the discharge of soaps, detergents or solvents used in vehicle washing. Installation Schedule: At the commencement of construction activities Maintenance and Once weekly and within 24 hours of the end of a rainfall event Inspection: that is 0.25 inches or greater. Washout spoil to be disposed of in on-site containers on a daily basis. Responsible Staff. CPPPP Contact and/or their responsible designee Page 8 Construction Period Pollution Prevention Plan(CPPPP) 480 Suite 3 Arsenal Street- Watertown, MA 3.4 Establish Proper Equipment/Vehicle Fueling and Maintenance Practices BMP Description: Fueling operations, including the service and storage of equipment associated with fueling, shall not occur within drainage areas with temporary sedimentation basins and a minimum of 100 feet from the edge of any resource area onsite. Installation Schedule: At the commencement of construction activities Maintenance and Once weekly and within 24 hours of the end of a rainfall event Inspection: that is 0.25 inches or greater Responsible Staff. CPPPP Contact and/or their responsible designee 3.5 Control Equipment/Vehicle Washing BMP Description: Vehicle washing shall occur only within drainage areas with temporary sedimentation basins. Installation Schedule: At the commencement of construction activities Maintenance and Once weekly and within 24 hours of the end of a rainfall event Inspection: that is 0.25 inches or greater Responsible Staff CPPPP Contact and/or their responsible designee 3.6 Spill Prevention and Control Plan A spill contingency plan will be implemented during construction,including the following provisions: • Equipment necessary to quickly attend to inadvertent spills will be stored on-site in a secure but accessible location. Such equipment will include: 1. safety goggles 2. chemically resistant gloves and overshoe boots 3. water and chemical fire extinguishers 4. sand and shovels 5. suitable absorbent materials 6. storage containers 7. first aid equipment • Spills or leaks will be treated properly in accordance with material type,volume of spillage and location of the spill. Mitigation will include: 1. preventing further spillage 2. containing the spilled material to the smallest practical area 3. removing spilled material immediately in a safe and environmentally sound manner and in accordance with all applicable codes Page 9 Construction Period Pollution Prevention Plan(CPPPP) 480 Suite 3 Arsenal Street- Watertown, MA 4. mitigating any damage to the environment • For spills of less than 5 gallons of material,proceed with source control and containment and clean up with absorbent materials or other applicable means,unless an imminent hazard or other circumstances dictate that the spill should be treated by a professional response contractor. • Spills of toxic or hazardous materials of any type will be reported to the appropriate federal, state and/or local government agency,regardless of the size of the spill. Spills of amounts that exceed reportable quantities of certain substances specifically mentioned in federal regulations 40 CFR 110,40 CFR 117 and 40 CFR 302 must be immediately reported to the EPA National Response Center,telephone 1-800-424-8802. 3.7 Any Additional BMPs BMP Description:Adequate sanitation facilities for on-site construction crews Installation Schedule: At the commencement of construction activities Maintenance and As required. Portable facilities shall be emptied and cleaned on a Inspection: weekly basis. Responsible Staff. CPPPP Contact and/or their responsible designee BMP Description:Dust control through watering Installation Schedule: As required throughout earthwork operations Maintenance and As required Inspection: Responsible Staff. CPPPP Contact and /or their responsible designee 3.8 Allowable Non-Stormwater Discharge Management BMP Description:All measures used to mitigate sedimentation shall be used to control water associated with dust control activities and uncontaminated excavation dewatering. Installation Schedule: As outlined in above measures Maintenance and Once weekly and within 24 hours of the end of a rainfall event Inspection: that is 0.25 inches or greater Responsible Staff. CPPPP Contact and/or their responsible designee Page 10 Construction Period Pollution Prevention Plan(CPPPP) 480 Suite 3 Arsenal Street- Watertown, MA SECTION 4: CONSTRUCTION PERIOD POLLUTION PREVENTION AND SEDIMENTATION PLAN FORMS AND LOGS Page 11 Construction Pollution Prevention Plan(CPPP) 480 Suite 3 Arsenal Street—Watertown, MA 4.1 Construction Site Inspection Report 480 Suite 3 Arsenal Street Watertown, MA General Information Project Name 480 Suite 3 Arsenal Street NPDES Tracking No. Location 480 Suite 3 Arsenal Street Watertown, MA Date of Inspection Start/End Time Inspector's Name(s) Inspector's Title(s) Inspector's Contact Info. Inspector's Qualifications Describe Present Phase of Construction Type of Inspection: ❑ Regular ❑ Pre-storm event ❑ During storm event ❑ Post-storm event Weather Information Has there been a storm event since the last inspection? ❑Yes ❑No If yes,provide: Storm Start Date & Time: Storm Duration(hrs): Approximate Amount of Precipitation (in): Weather at time of this inspection? ❑ Clear ❑Cloudy ❑ Rain ❑ Sleet ❑ Fog ❑ Snowing ❑ High Winds ❑ Other: Temperature: Have any discharges occurred since the last inspection? ❑Yes ❑No If yes, describe: Are there any discharges at the time of inspection? ❑Yes ❑No If yes, describe: BMP BMP Installed? Maintenance Corrective Action Needed and Notes Required? 1 Catch Basin Filter Bag ❑Yes ❑No ❑Yes ❑No 2 Straw Wattles ❑Yes ❑No ❑Yes ❑No 3 Check Dams ❑Yes ❑No ❑Yes ❑No 4 Diversion Swales ❑Yes ❑No ❑Yes ❑No 5 Sedimentation Basins ❑Yes ❑No ❑Yes ❑No 6 Construction Entrance ❑Yes ❑No ❑Yes ❑No 7 Street Sweeping ❑Yes ❑No ❑Yes ❑No 8 Slope Stabilization ❑Yes ❑No ❑Yes ❑No 9 10 Construction Pollution Prevention Plan(CPPP) 480 Suite 3 Arsenal Street—Watertown, MA Overall Site Issues Below are some general site issues that should be assessed during inspections. Customize this list as needed for conditions at your site. BMP/Activity Implemented? Maintenance Corrective Action Needed and Notes Required? Are all slopes and 1 disturbed areas not ❑yes ❑No ❑Yes ❑No actively being worked properly stabilized? Are natural resource areas (e.g., streams, 2 wetlands,mature trees, ❑Yes ❑No ❑Yes ❑No etc.)protected with barriers or similar BMPs? Are perimeter controls and sediment barriers 3 adequately installed ❑Yes ❑No ❑Yes ❑No (keyed into substrate) and maintained? Are discharge points and 4 receiving waters free of ❑Yes ❑No ❑Yes ❑No any sediment deposits? 5 Are storm drain inlets ❑Yes ❑No ❑Yes ❑No properly protected? Is the construction exit 6 preventing sediment from ❑Yes ❑No ❑Yes ❑No being tracked into the street? Is trash/litter from work 7 areas collected and ❑yes ❑No ❑Yes ❑No placed in covered dumpsters? Are washout facilities (e.g.,paint, stucco, 8 concrete) available, ❑Yes ❑No ❑Yes ❑No clearly marked, and maintained? Are vehicle and equipment fueling, 9 cleaning, and ❑yes ❑No ❑Yes ❑No maintenance areas free of spills, leaks, or any other deleterious material? Are materials that are 10 potential stormwater ❑yes ❑No ❑Yes ❑No contaminants stored inside or under cover? 11 Are non-stormwater ❑Yes ❑No ❑Yes ❑No Construction Pollution Prevention Plan(CPPP) 480 Suite 3 Arsenal Street—Watertown, MA BMP/Activity Implemented? Maintenance Corrective Action Needed and Notes Required? discharges (e.g.,wash water, dewatering) properly controlled? 12 ❑Yes ❑No ❑Yes ❑No Non-Compliance Describe any incidents of non-compliance not described above: CERTIFICATION STATEMENT "I certify under penalty of law that this document and all attachments were prepared under my direction or supervision in accordance with a system designed to assure that qualified personnel properly gathered and evaluated the information submitted. Based on my inquiry of the person or persons who manage the system, or those persons directly responsible for gathering the information, the information submitted is, to the best of my knowledge and belief, true, accurate, and complete. I am aware that there are significant penalties for submitting false information, including the possibility of fine and imprisonment for knowing violations." Print name and title: Signature: Date: Construction Pollution Prevention Plan(CPPP) 480 Suite 3 Arsenal Street—Watertown, MA Corrective Action Log Project Name: 480 Suite 3 Arsenal Street CPPPP Contact: Inspection Inspector Description of BMP Deficiency Corrective Action Needed (including Date Action Date Name(s) planned date/responsible person) Taken/Responsible person Construction Pollution Prevention Plan (CPPP) 480 Suite 3 Arsenal Street—Watertown, MA Construction Period Pollution Prevention and Sedimentation Plan Amendment Log Project Name: 480 Suite 3 Arsenal Street CPPPP Contact: Amendment No. Description of the Amendment Date of Amendment Amendment Prepared by [Name(s) and Title] Construction Pollution Prevention Plan(CPPP) 480 Suite 3 Arsenal Street—Watertown, MA Subcontractor Certifications/Agreements SUBCONTRACTOR CERTIFICATION STORMWATER POLLUTION PREVENTION PLAN Project Number: Project Title: Operator(s): As a subcontractor, you are required to comply with the Stormwater Pollution Prevention Plan (SWPPP) for any work that you perform on-site. Any person or group who violates any condition of the SWPPP may be subject to substantial penalties or loss of contract. You are encouraged to advise each of your employees working on this project of the requirements of the SWPPP. A copy of the SWPPP is available for your review at the office trailer. Each subcontractor engaged in activities at the construction site that could impact stormwater must be identified and sign the following certification statement: I certify under the penalty of law that I have read and understand the terms and conditions of the SWPPP for the above designated project and agree to follow the BMPs and practices described in the SWPPP. This certification is hereby signed in reference to the above named project: Company: Address: Telephone Number: Type of construction service to be provided: Signature: Title: Date: Construction Pollution Prevention Plan(CPPP) 480 Suite 3 Arsenal Street—Watertown, MA Grading and Stabilization Activities Log Project Name: 480 Suite 3 Arsenal Street CPPPP Contact: Date Description of Grading Activity Date Grading Date When Description of Stabilization Measure and Grading Activity Ceased Stabilization Location Activity (Indicate Measures are Initiated Temporary or Initiated Permanent) Construction Pollution Prevention Plan(CPPP) 480 Suite 3 Arsenal Street—Watertown, MA CPPPP Training Log Stormwater Pollution Prevention Training Log Project Name: 480 Suite 3 Arsenal Street Project Location: 480 Suite 3 Arsenal Street—Watertown, MA Instructor's Name(s): Instructor's Title(s): Course Location: Date: Course Length (hours): Stormwater Training Topic: (check as appropriate) ❑ Erosion Control BMPs ❑ Emergency Procedures ❑ Sediment Control BMPs ❑ Good Housekeeping BMPs ❑ Non-Stormwater BMPs Specific Training Objective: Attendee Roster: (attach additional pages as necessary) No. Name of Attendee Company � 1 � 2 � 3 � 4 � 5 � 6 � 7 � 8 � 9 10 Construction Pollution Prevention Plan(CPPP) 480 Suite 3 Arsenal Street—Watertown, MA Delegation of Authority Form Delegation of Authority I, (name), hereby designate the person or specifically described position below to be a duly authorized representative for the purpose of overseeing compliance with environmental requirements, including the Construction General Permit, at the construction site. The designee is authorized to sign any reports, stormwater pollution prevention plans and all other documents required by the permit. (name of person or position) (company) (address) (city, state, zip) (phone) By signing this authorization, I confirm that I meet the requirements to make such a designation as set forth in (Reference State Permit), and that the designee above meets the definition of a"duly authorized representative" as set forth in (Reference State Permit). I certify under penalty of law that this document and all attachments were prepared under my direction or supervision in accordance with a system designed to assure that qualified personnel properly gathered and evaluated the information submitted. Based on my inquiry of the person or persons who manage the system, or those persons directly responsible for gathering the information, the information submitted is, to the best of my knowledge and belief, true, accurate, and complete. I am aware that there are significant penalties for submitting false information, including the possibility of fine and imprisonment for knowing violations. Name: Company: Title: Signature: Date: Construction Period Pollution Prevention Plan (CPPPP) 480 Suite 3 Arsenal Street - Watertown, MA APPENDICES: Appendix A — Figures Figure I USGS Site Locus Plan Appendix B —Site Plans Site Plans entitled "Site Plan for 480 Suite 3 Arsenal Street, Watertown, MA"— Under Separate Cover Construction Period Pollution Prevention Plan (CPPPP) 480 Suite 3 Arsenal Street - Watertown, MA Appendix A — Figures O Q �; �o \ Q ao ' IN .% - CM �o ST h J I Wate own ._..� e . ��� �\ Fillippel� 50 LAUREL �o LA \ z I �� PlaY9. 1tA ti �A,�sE t� S:a v rin s? NAL.,ST S i T IIE I . Pond /w0�LEYiAVEJ- =i 50 c�— R \Es.RivER� ® 20 MIDDLESEX-CO,� Whanles River '��` �� SUFFOLKKcCO � ,; ;aneull rToo ; �� �� - CO :Z5Mi in All 1,000 0 500 1,000 2,000�`\ —. Lug = GRAPHIC SCALE IN FEET <N` V� \ �y # ��P'�r—,n. P.J. by., Project Nome: Oroeiog Name: Droerinq No.: Designetl by M Drawn by ems RJO'Cor aEu 480 SUITE 3 MM LOM 1 FIG.Cbeckea by RlS !ASSOCIATES,INC. ARSENAL STREET u.D 1 1 scale 1'=1,000' ,.Y- Date 02/10/2015 WATERTOWN,MA No. RENSION DATE/ ♦ �••,•,.3140�� "*- 4II74 Copyright©2015 by R J.O'Connell&A..—ot-,Inc Drawing name: G\MA\Watertown\Boylston Properties\480 Arsenal Street\Reports\Stormwater Report\Figures\14074-FIG 1 USGS Locus Map.dwg Feb 06, 2015 - 12:11 pm Construction Period Pollution Prevention Plan (CPPPP) 480 Suite 3 Arsenal Street - Watertown, MA Appendix B — Site Plans Under Separate Cover Operations and Maintenance Plan 480 Suite 3 Arsenal Street Watertown, Massachusetts Prepared for: Boylston Properties 800 Boylston Street Boston, MA 02199 Prepared by: R.J. O'Connell & Associates, Inc. 80 Montvale Ave, Suite 201 Stoneham, MA 02180 Date: February 10, 2015 Revised: March 27, 2015 TABLE OF CONTENTS Introduction Section 1 -Stormwater Management System— Operations and Maintenance Section 2 -Long Term Pollution Prevention Plan (LTPPP) A. Materials Covered B. Materials Management Practices C. Spill Prevention and Response Procedures Section 3 - Illicit Discharge Statement Section 4 - Snow Management and Disposal Plan Section 5 - Public Safety Features Appendices Appendix A - 480 Suite 3 Arsenal Street Maintenance and Inspection Forms Activity Guide Comprehensive Annual Evaluation and Inspection Report Annual Training Signoff Sheet Weekly Inspection Checklist Monthly Inspection Checklist Quarterly Inspection Checklist Semi-Annually Inspection Checklist Spill and Leak History CDS Inspection and Maintenance Guide Operations and Maintenance Plan INTRODUCTION This Operations and Maintenance Plan has been prepared to ensure that the stormwater management system implemented for 480 Suite 3 Arsenal Street to functions as designed and to develop and carry out suitable practices for source control and pollution prevention. It consists of six sections: Section 1 - Stormwater Management System-Operations and Maintenance, which describes the various components of the stormwater management system, identifies the inspection and maintenance tasks to be undertaken after construction is complete and a schedule for implementing these tasks to insure the proper, long-term operation of the system. Section 2 - Long Term Pollution Prevention Plan which identifies and implements suitable measures,practices and procedures for source control and pollution prevention. Section 3- Illicit Discharge Statement. Section 4- Snow Management and Disposal Plan which describes how snow removal will be managed and deicing operations performed. Section 5-Public Safety Features which lists features of the stormwater management system to insure the safety of the public. 1 SECTION 1 —STORMWATER MANAGEMENT SYSTEM- OPERATION AND MAINTENANCE The objectives of the stormwater management system are to effectively control and treat stormwater runoff from the site in accordance with the Massachusetts Stormwater Management Standards. To accomplish this objective, the following Best Management Practices (BMP's) are included in the proposed office building's stormwater management system: Pre-treatment BMP's • Sweeping of paved surface areas to remove solids and reduce suspended solids in surface runoff. • Maintaining the existing catch basins to reduce the discharge of sediment and pollutants. • Maintaining oil/particle separators for removal of Total Suspended Solids (TSS), oil and grease. Treatment BMP's • Maintaining the subsurface infiltration system to recharge groundwater, reduce peak rates of runoff from the site and remove suspended solids from stormwater runoff through infiltration into the ground. To ensure the ongoing and proper functioning of the on-site stormwater management/BMP facilities, this Operations and Maintenance Plan has been developed. In consideration of the foregoing, it is the ongoing responsibility of the Landowner, his successors and assignees to adequately maintain the on-site stormwater management/BMP facilities. Adequate maintenance is herein defined as good working condition so that these facilities are performing their design functions. Based on this, the Landowner, his successors and assignees are required to create a Pollution Prevention Team(PPT)that will be responsible for implementing the Operations and Maintenance Plan. Upon transfer of ownership of the property, the Landowner is required to notify the new owner of the presence of the stormwater management system and the requirements of this Operations and Maintenance Plan. Property Information Address: 480 Suite 3 Arsenal Street Watertown, MA 02472 2 Landowner and Pollution Prevention Team Leader Owner's Name: Boylston Properties Team Leader: TBD Title: Owner Office Phone: TBD Email: TBD Responsibilities: Coordinate all aspects of the Operations and Maintenance Plan, coordinate and hire the other Pollution Prevention team members in order to conduct inspections, keep all records, coordinate with contractors for maintenance and repairs of the stormwater management system. Shill Prevention& Control Contractor The following contacts shall be notified only in those instances identified within MA DEP-310 CMR 40-subpart C. Primary Contact: TBD Office Phone: TBD Emergency Contact: Company Name: TBD Contact Name: TBD Emergency Phone: TBD Consultant Contact: Company Name: TBD Contact Name: TBD Phone: TBD Department of Environmental Protection (DEP) Contact Spill Emergency Coordinator Contact Name: TBD Phone: TBD Municipal Contacts Contact Name: Town of Watertown, Department of Public Works, Gerald S. Mee, Jr., Superintendent Phone: 781-972-6420 Other Pollution Prevention Team Members Member: Qualified Engineering and/or Environmental Consulting Firm(s) Responsibilities: Conduct scheduled inspections, maintain records, advise the Team Leader of maintenance needs, ensure inspection maintenance and repairs are completed, keep and maintain all records and inspection reports. 3 Company Name(s): TBD Address: Office Phone: Team Member Training The Pollution Prevention Team Leader will coordinate an annual in-house training session with the qualified Engineering and/or Environmental Consulting Firm to discuss the Operations and Maintenance Plan, ongoing inspection and maintenance and preventative maintenance procedures. Annual training session will generally include the following: • Discuss the Operations and Maintenance Plan o What it is- identify potential sources of stormwater pollution and methods of reducing or eliminating that pollution o What it contains- emphasize good housekeeping measures and location of potential pollution sources. o Pollution Prevention Team- introduce the team and responsibilities, explain that the objective is to continually monitor the stormwater management system and encourage input and assistance from all. • Review and explain the storm drainage system, how it works and its components, note the receiving resource area in which the storm drainage system discharges into and the role each one of these areas play. • Emphasize the importance of maintaining current and up-to-date inspection reports and maintenance records of BMP's. Documentation shall include any changes to the O&M Plan's procedures to accommodate changes and revisions to BMP's. The components of the stormwater management system must be inspected, monitored and maintained in accordance with the following in order to ensure that the on-site stormwater management/BMP facilities for the 480 Suite 3 Office Building are functioning as designed. Routine inspection and proper maintenance of these individual components is essential to providing the long-term enhancement of both the quality and quantity of the runoff from the property. Catch Basins: Stormwater runoff from pavement areas is directed to the existing catch basins via curbing and site grading. To ensure proper functioning of catch basins, each on-site catch basin will be inspected and maintained as follows: Inspection: Quarterly and after major storm events (3.2 inches or more in a 24 hour period). Structural damage and other malfunctions to be noted and reported. 4 Maintenance: Cleaned four times a year or when the sump is half full by a licensed contractor. Sediment and hydrocarbons will be properly handled and legally disposed of off site in accordance with local, state, and federal guidelines and regulations. Any structural damage to catch basins and/or castings will be repaired upon discovery. Sweevin2 and Site Clean-Un Routine sweeping of paved areas is an effective method to provide important nonpoint source pollution control and will be performed by mechanical sweepers. Most stormwater pollutants travel with the suspended solids contained in the stormwater runoff and regular sweeping will help reduce a portion of this load. Sweeping, especially during the period immediately following winter snowmelt (March/April) when road sand and other debris has accumulated on the pavement, will capture a peak sediment load before spring rains wash residual sand from winter applications into nearby resource areas. Inspection: Paved areas will be inspected for litter on a weekly basis and picked up and disposed of immediately. Maintenance: All parking areas, sidewalks, driveways and other impervious surfaces (except roofs)will be swept clean of sand, litter, trash, etc. on a monthlv basis. A log of land/lot sweeping and cleanup will be kept. Housekeeping concerns noted by store leadership, PPT members, guests and others will be noted and acted upon. Separate cleanup services will be conducted at least twice a year, once between November 14 and December 15 (after leaf fall) and once during the month of April (after snow melt). Additional cleanup services will be conducted as necessary. CDS Oil/Particle Separators The Continuous Deflective Separator(CDS)unit separates and traps debris, sediment and oil and grease from stormwater runoff. The indirect screening capability of the system allows for 100%removal of floatables and neutrally buoyant material. There are four CDS units on site designed to treat stormwater runoff prior to discharging into the subsurface infiltration systems. Inspection: Quarterly Maintenance: Jet/vacuumed by a licensed contractor at least twice per year. Accumulated sediment and hydrocarbons will be disposed of in accordance with applicable local, state and federal guidelines and regulations. 5 Rain Garden The rain garden is an integral part of the overall stormwater management plan providing treatment of storm runoff using soils and plants before it is infiltrated into the ground or discharged. Inspection: During the first six months after installation, inspect following the first two precipitation events of at least 1.0 inches to ensure that the rain garden is functioning properly. Thereafter, inspect area once a year and after rainfall events of 3.2 inches or more in a 24 hour period for slope integrity, vegetative health, ponding, and sediment accumulation. Maintenance: Maintenance includes removing trash and debris monthly. Prune or replace dead vegetation twice per year(spring and fall). Separate herbaceous vegetation rootstock when over-crowding is observed, or approximately once every 3 years. Silt/sediment shall be removed when the accumulation exceeds one inch or when water ponds on the surface of the filter bed for more than 48 hours. Replenish the mulch layer to original depth every other year. Remove the previous mulch layer and dispose of properly. Do not plow or store snow in the rain garden. Sediment Forebav The sediment forebay allows for settling of sediments and removal of debris and pollutants from the stormwater prior to discharging into the water quality swale. It provides additional pretreatment of runoff and slows the velocity of incoming stormwater to the water quality Swale. Inspection: The forebay will be inspected monthly or after major storm events for trash, excessive sediment build up, and erosion scouring of the side slopes and under the flared end pipe inlets. Maintenance: The forebay will be cleaned four times per year. Trash will be removed on a monthly basis. Sediment will be properly handled and disposed of the site by a licensed contractor in accordance with local, state, and federal guidelines. Any erosion scouring within the forebay will be repaired immediately and disturbed areas loamed and seeded or rip-rapped. Do not plow or store snow in the rain garden. Water Oualitv Swale The water quality swale is an important part of the overall stormwater management plan providing pretreatment of storm runoff prior to discharge to the subsurface infiltration system. 6 Inspection: Once a month during the first few months after installation to ensure that vegetation in the swale has become adequately established. Thereafter, inspect swale twice a year for slope integrity, soil moisture, vegetative health, soil stability, soil compaction, soil erosion, ponding, and sedimentation. Maintenance: Regular maintenance includes mowing, fertilizing, liming, watering pruning and weed and pest control. Do not cut grass shorter than three (3) to four(4) inches. Do not let grass height exceed six(6) inches. Annually remove sediment and debris and re-seed if necessary. Do not plow or store snow in swale. Use only organic,phosphorus-free, slow-release fertilizers on site. Phosphorus- containing fertilizers can be used in minimal concentrations/amounts where soil tests conclude that its absence is prohibiting plant establishment. Subsurface Infiltration Svstems Subsurface infiltration systems are located beneath the east, south and west parking areas. The systems consists of either 3 or 5 foot diameter, perforated, corrugated metal pipes surrounded in crushed stone. The system's is designed to temporarily retain storm runoff and percolate it into the underlying soil. Inspection: Inlets to be inspected twice a year. Maintenance: Clean when there is a build-up of visible sediment at the inlet. Sediment to be removed by jet vacuum and disposed of legally in accordance with local, state and federal guidelines and regulations. Please refer to Appendix A for the Inspection Forms,which are to be used by the Pollution Prevention Team member responsible for conducting the scheduled inspections. 7 SECTION 2 —LONG TERM POLLUTION PREVENTION PLAN (LTPPP) A. MATERIALS COVERED The following materials or substances are expected to be present onsite after construction: Cleaning solvents Petroleum based products Detergents Pesticides/Insecticides Paints/Solvents Fertilizers/Herbicides Acids Pet waste Solid Waste Contaminated Soil B. MATERIALS MANAGEMENT PRACTICES The following are the material management practices that will be used to reduce the risk of spills or other accidental exposure of materials and substances to stormwater runoff. The Pollution Prevention Team Leader will be responsible for ensuring that these procedures are followed: 1. Good Housekeeping The following good housekeeping practices will be followed onsite after construction: a) An effort will be made to store only enough products required to do the job. b) All materials stored onsite will be stored in a neat, orderly manner and, if possible,under a roof or in a containment area. At a minimum, all containers will be stored with their lids on when not in use. Drip pans shall be provided under all dispensers. c) Products will be kept in their original containers with the original manufacturer's label in legible condition. d) Substances will not be mixed with one another unless recommended by the manufacturer. e) Whenever possible, all of a product will be used up before disposing of the container. f) Manufacturer's recommendations for proper use and disposal will be followed. g) A Pollution Prevention Team Member will be responsible for daily inspections to ensure proper use and disposal of materials. 2. Hazardous Substances These practices will be used to reduce the risks associated with Hazardous Substances. Material Safety Data Sheets (MSDS's) for each product with 8 hazardous properties that is used at the Project will be obtained and used for the proper management of potential wastes that may result from these products. An MSDS will be posted in the immediate area where such product is stored and/or used and another copy of each MSDS will be maintained on-site, in the management office. Each employee who must handle a Hazardous Substance will be instructed on the use of MSDS sheets and the specific information in the applicable MSDS for the product he/she is using,particularly regarding spill control techniques. a) Products will be kept in original containers with the original labels in legible condition. b) Original labels and MSDS's will be procured and used for each product. c) If surplus product must be disposed of, the manufacturer's and local/state/federal required methods for proper disposal must be followed. 3. Hazardous Waste It is imperative that all Hazardous Waste be properly identified and handled in accordance with all applicable Hazardous Waste Standards, including the storage, transport and disposal of the Hazardous Wastes. There are significant penalties for the improper handling of Hazardous Wastes. It is important that the Pollution Prevention Team Leader seeks appropriate assistance in making the determination of whether a substance or material is a Hazardous Waste. For example, Hazardous Waste may include certain Hazardous Substances, as well as pesticides,paints, paint solvents, cleaning solvents, contaminated soils, and other materials, substances or chemicals that have been discarded(or are to be discarded) as being out-of-date, contaminated, or otherwise unusable. The Pollution Prevention Team Leader is responsible for ensuring that all Pollution Prevention Team Members are instructed as to these Hazardous Waste requirements and also that the requirements for handling and disposal are being followed. 4. Product Specific Practices The following product specific practices will be followed on the job site: a) Petroleum Products Petroleum products will be stored in tightly sealed containers which are clearly labeled. Petroleum storage tanks shall be located a minimum of 100 linear feet from wetland resource areas, drainage ways, inlets and surface waters unless stored within a building. Any petroleum storage tanks stored onsite will be located within a containment area that is designed with an impervious surface between the tank and the ground. The secondary containment must be designed to provide a containment volume that is equal to 110% of the volume of the largest tank. Drip pans shall be provided for 9 all dispensers. Any asphalt substances used onsite will be applied according to the manufacturer's recommendations. The location of any fuel tanks and/or equipment storage areas must be identified on the Erosion Control Plan by the Contractor once the locations have been determined. b) Fertilizers, Herbicides, Pesticides, and Insecticides Fertilizers, herbicides,pesticides, insecticides and/or pool chemicals will be applied only in the minimum amounts recommended by the manufacturer. Once applied, they will be worked so as to limit exposure to storm water. Storage will be in a covered shed. The contents of any partially used bags or containers will be transferred to a sealable plastic bin to avoid spills. c) Paints, Paint Solvents, and Cleaning Solvents All containers will be tightly sealed and stored when not in use. Excess paint and solvents will not be discharged to the storm sewer system but will be properly disposed of according to manufacturer's instructions or state and federal regulations. 5. Solid Waste All waste materials will be collected and stored in an appropriately covered container and/or securely contained metal dumpster rented from a local waste management company which must be a licensed solid waste management company. The dumpster will comply with all local and state solid waste management regulations. All trash and debris from the site will be deposited in dumpsters. The dumpsters will be emptied a minimum of once per week or more often if necessary. All personnel will be instructed regarding the correct procedures for waste disposal. All waste dumpsters and roll-off containers will be located in an area where the likelihood of the containers contributing to storm water discharges is negligible. No debris, refuse or other materials, including but not limited to landscaping debris, leaves, shrubs and tree trimmings, logs, bricks stone or trash shall be deposited within the vegetated wetland or within 100 feet of the vegetated wetland. 6. Contaminated Soils Any contaminated soils (resulting from spills of Hazardous Substances or Oil) will be contained and cleaned up immediately in accordance with the procedures given in the Materials Management Plan and in accordance with applicable state and federal regulations. If there is a release, it should be reported as a spill, if it otherwise meets the requirements for a reportable spill. 10 7. Pet Waste The site will be inspected weekly for pet waste. Pet waste will be collected, placed in a closed, tied trash bag and disposed of in accordance with applicable code requirements. C. SPILL PREVENTION AND RESPONSE PROCEDURES The Pollution Prevention Team Leader will train all personnel in the proper handling and cleanup of spilled Hazardous Substances or Oil. No spilled Hazardous Substances or Oil will be allowed to come in contact with storm water discharges. If such contact occurs, the storm water discharge will be contained on site until appropriate measures in compliance with state and federal regulations are taken to dispose of such contaminated storm water. It shall be the responsibility of the Pollution Prevention Team Leader to be properly trained, and to train all personnel in spill prevention and clean up procedures. 1. In order to prevent or minimize the potential for a spill of Hazardous Substances or Oil to come into contact with storm water, the following steps will be implemented: a) All Hazardous Substances or Oil (such as pesticides, petroleum products, fertilizers, detergents, acids, paints,paint solvents, cleaning solvents, etc.)will be stored in a secure location, with their lids on,preferably under cover, when not in use. b) The minimum practical quantity of all such materials will be kept on site. c) A spill control and containment kit (containing, for example, absorbent materials, acid neutralizing powder, brooms, dust pans, mops, rags, gloves, goggles,plastic and metal trash containers, etc.)will be provided on site. d) Manufacturer's recommended methods for spill cleanup will be clearly posted and site personnel will be trained regarding these procedures and the location of the information and cleanup supplies. e) It is the Pollution Prevention Team Leader's responsibility to ensure that all Hazardous Waste on site is disposed of properly by a licensed hazardous material disposal company. The Pollution Prevention Team Leader is responsible for not exceeding Hazardous Waste storage requirements mandated by the EPA or state and local authority. 2. In the event of a spill of Hazardous Substances or Oil, the following procedures must be followed: a) All measures must be taken to contain and abate the spill and to prevent the discharge of the Hazardous Substance or Oil to storm water or off-site. (The spill area must be kept well ventilated and personnel must wear appropriate protective clothing to prevent injury from contact with the Hazardous Substances.) II b) For spills of less than five (5) gallons of material, proceed with source control and containment, clean-up with absorbent materials or other applicable means unless an imminent hazard or other circumstances dictate that the spill should be treated by a professional emergency response contractor. c) For spills greater than five (5) gallons of material immediately contact the MA DEP Hazardous Waste Incident Response Group at (617) 792-7653 and an approved emergency response contractor. Provide information on the type of material spilled, the location of the spill, the quantity spilled, and the time of the spill to the emergency response contractor or coordinator, and proceed with prevention, containment and/or clean-up if so desired. d) If there is a Reportable Quantity(RQ)release, then the National Response Center will be notified immediately at(800) 424-8802; within 14 days a report will be submitted to the EPA regional office describing the release, the date and circumstances of the release and the steps taken to prevent another release. This Pollution Prevention Plan must be updated to reflect any such steps or actions taken and measures to prevent the same from reoccurring. 3. The Pollution Prevention Team Leader will be the spill prevention and response coordinator. He/she will designate the individuals who will receive spill prevention and response training. These individuals will each become responsible for a particular phase of prevention and response. The names of these personnel will be posted in the material storage area and in the management office. 12 SECTION 3 -ILLICIT DISCHARGE STATEMENT Certain types of discharges are allowable under the U.S. Environmental Protection Agency Construction General Permit, and it is the intent of this LTPPP to allow such discharges. These types of discharges will be allowed under the conditions that no pollutants will be allowed to come in contact with the water prior to or after its discharge. The control measures which have been outlined previously in this LTPPP will be strictly followed to ensure that no contamination of these non-storm water discharges takes place. Illicit discharges, if they exist currently, will be contained and eliminated in the manner specified by local, state and federal regulations, and will be prohibited in the proposed development. Jeff Heidelberg for Boylston Properties 13 SECTION 4 - SNOW MANAGEMENT AND DISPOSAL PLAN Snow management will be overseen by a full-time Property Manager who will implement this plan and be authorized to utilize additional resources should unusual events occur. The Snow Management Contractor(SMC) shall be responsible for maintaining all roads, driveways, parking lots, sidewalks and pedestrian access areas for clear and safe travel. The SMC shall report directly to the Property Manager and maintain communication via cell phones 24 hours per day, 7 days per week. All roads, drives, entrances and exits are the first priority. During extreme events, the first priority will be to clear and maintain proper access for residents and public safety vehicles. The next priority is parking areas, sidewalks, fire hydrants, and delivery areas. Snow will not be piled around light bases and handicap parking areas shall be cleared frequently. The anti-icing operations typically precede snow plowing and will be provided when conditions warrant. Within 12 months of concrete walks,pads, or other features being poured, no salt shall be placed on those surfaces. After the materials have cured for 12 months, a combination of salt(Halite or Rock Salt) and sand("washed", fine to medium grade) shall be utilized. Parking areas shall receive spot treatment only when and where needed in a similar manner. Snow plowing shall commence upon accumulation of two inches ("2") or more. Snow shall be deposited in designated areas. The SMC shall keep existing catch basins open for drainage or water resulting from melting. Once the storm is over, the SMC shall monitor all areas on-site for icy spots and snowdrifts. If needed, an application of sand and salt will be applied to all streets and roads so that the riding surface remains drivable. When the ambient temperature drops below 25 degrees F, all major areas will receive an application of pre-wetted salt with calcium chloride to maintain melting action and an ice-free surface for as long as possible. Salt loses its effectiveness at temperatures drop below 25 degrees F. Deicing chemicals will be kept in original containers with the original product label in legible condition. When not in use, deicing materials will be stored in a neat, orderly manner under cover with their container lids on. 14 SECTION 5 - PUBLIC SAFETY FEATURES The following measures have been incorporated into the stormwater management system to insure the safety of the public: • Storm drain manholes and catch basins provided with heavy duty covers and/or grates and designed to withstand H2O loading. • Control and collection of stormwater runoff through positive drainage and curbing directing it toward drainage inlet structures. • Treatment of stormwater runoff from paved surfaces to remove 80% of the average annual post-construction load of Total Suspended Solids (TSS). • Reduction in peak rates of runoff and volume from the site under post- redevelopment conditions as compared to pre-developed conditions. • Development and implementation of an Operations and Maintenance Plan to insure the proper functioning of the stormwater management system and a Long Term Pollution Prevention Plan identifying potential pollution sources and suitable practices to control and prevent them from impacting the environment and/or the public's health and safety. 15 Appendix A 480 Suite 3 Arsenal Street Maintenance and Inspection Forms 16 480 Suite 3 Arsenal Street Operation and Maintenance Plan Activity Guide The table below is a list of the minimum inspection and maintenance activities the Pollution Prevention Team needs to conduct for the Stormwater Operations and Management Plan and who is responsible for the activity. The Activity Guide is provided to assist the Pollution Prevention Team Leader and ensure that the activities are being conducted as scheduled. Timing Activity Responsible Party Weekly Inspect lot/land PPT Pet waste management PPT Parking lot sweeping PPT Contractor Monthly Clean rain garden of trash and debris PPT/Contractor Inspect sediment forebay and remove trash and debris PPT/Contractor Quarterly Inspect and clean catch basins PPT/Contractor Inspect CDS oil/particle separators PPT/Contractor Clean sediment forebay PPT/Contractor Semi-Annually Clean CDS Oil/Particle Separators PPT/Contractor Inspect water quality swale PPT/Contractor Inspect rain garden PPT/Contractor Inspect subsurface infiltration systems PPT/Contractor Prune dead vegetation in rain garden PPT/Contractor Annually Pollution Prevention Team training PPT Leader Comprehensive annual stormwater evaluation and PPT Leader inspection report Remove sediment and debris from water quality swale PPT/Contractor April Spring clean-up, PPT/Contractor Between Fall clean-up PPT/Contractor November 14 and December 15 480 Suite 3 Arsenal Street Operations and Maintenance Plan Comprehensive Annual Evaluation and Inspection Report Once a year, the Pollution Prevention Team Leader must inspect and evaluate all aspects and provisions of the Opeations and Maintenance Plan, complete the following report and keep a copy on file at the site. Inspector/Reviewers: Date of Inspection/Review: Note any changes to the Plan in the space below and in the appropriate section of the Plan. 1. Review the Pollution Prevention Team list and update if necessary. Does the Pollution Prevention Team list need updating: (circle one) Yes No 2. Review the Operations and Maintenance Plan(O&M Plan). Are there sections of the O&M Plan that need updating? (circle one) Yes No 3. Review Monthly and Weekly Checklists. Update these as necessary -Are there any updates needed to Spill and Leak History and/or the checklists? (circle one) Yes No 4. Review site drawings and update if necessary Are there updates needed to any of the drawings? (circle one) Yes No Requested Changes (attach revisions) 480 Suite 3 Arsenal Street Operations and Maintenance Plan Annual Training Signoff Sheet For each Operations and Maintenance Plan training session, the Team Leader should keep records of all attending Team Members using the signoff sheet below, as well as the training agenda, notes, etc. Training Date: Topic: Trainer: Team Member Name Team Member Signature 480 Suite 3 Arsenal Street Operations and Maintenance Plan Weekly Inspection Checklist The site will be checked each week for trash and debris by a member of the Pollution Prevention Team. If any trash or debris is observed in the specified area, write "yes" in the 2nd column and note the problem and corrective measures taken in the appropriate space. Make a new copy of this checklist each week. Date: Checklist completed by: GROUNDS AREA TO TRASH OR DEBRIS PRESENT? DESCRIPTION OF CORRECTIVE MEASURES CHECK PROBLEM TAKEN Parking Lot& Roadways Landscaped Areas Compactor/Dumpster& Loading Dock Areas Perimeter of Property 480 Suite 3 Arsenal Street Operations and Maintenance Plan Monthly Inspection Checklist The following will be checked each month for sources of pollutants by a member of the Pollution Prevention Team. If the condition in the "check for" column is observed, note the problem and corrective measures taken in the appropriate space. Make a new copy of the checklist each month. Date: Checklist completed by: LOCATION CHECK FOR... DESCRIPTION OF CORRECTIVE MEASURES PROBLEM (IF PRESENT) TAKEN Loading Dock Areas Evidence of Spills or Leaks, Spill Response equipment, Trash Parking Lot and Paved Spillage and Trash Areas Perimeter of Site Trash Outside Storage Areas Spillage (grease, etc.) Rain Garden Remove trash and debris Sediment Forebay Inspect and remove trash and debris 480 Suite 3 Arsenal Street Operations and Maintenance Plan Quarterly Inspection Checklist The following will be checked each quarter for sources of pollutants by a member of the Pollution Prevention Team. If the condition in the "check for" column is observed, note the problem and corrective measures taken in the appropriate space. Make a new copy of the checklist each month. Date: Checklist completed by: BMP CHECK FOR... DESCRIPTION OF CORRECTIVE MEASURES PROBLEM (IF PRESENT) TAKEN Catch Basins Trash, oil sheen, hood (securely fastened) excessive sediment CDS Oil/Particle Trash, excessive sediment Separator Sediment Forebay Clean forebay of accumulated sediment, trash and debris 480 Suite 3 Arsenal Street Operations and Maintenance Plan Semi-Annually Inspection Checklist The following will be checked each quarter for sources of pollutants by a member of the Pollution Prevention Team. If the condition in the "check for" column is observed, note the problem and corrective measures taken in the appropriate space. Make a new copy of the checklist each month. Date: Checklist completed by: BMP CLEAN AND REMOVE... DESCRIPTION OF CORRECTIVE MEASURES PROBLEM (IF PRESENT) TAKEN Subsurface Infiltration Trash, excessive sediment at inlets System CDS Oil/Particle Trash, excessive sediment Separator Rain Garden Prune dead vegetation Water Quality Swale Check vegetation health, ponding and sediment accumulation 480 Suite 3 Arsenal Street Operations and Maintenance Plan Annual Inspection Checklist The following will be checked each quarter for sources of pollutants by a member of the Pollution Prevention Team. If the condition in the "check for" column is observed, note the problem and corrective measures taken in the appropriate space. Make a new copy of the checklist each month. Date: Checklist completed by: BMP CLEAN AND REMOVE... DESCRIPTION OF CORRECTIVE MEASURES PROBLEM (IF PRESENT) TAKEN Water Quality Swale Sediment, trash and debris Pollution Prevention Prepare annual stormwater evaluation Team Training and inspection report 480 Suite 3 Arsenal Street Long Term Pollution Prevention Plan Spill and Leak History ( to ) Date Spill Leak Location Description Response Measures to Reporting Procedures Prevent Pollution Reoccurrence Prevention Team Member (MM/DD/YY) (check one) (as indicated on Type of Quantity Source, if Reason Site Map) Material known CONSTRUCTION PRODUCTS INC. CDS° Inspection and Maintenance Guide Y ; DS;It . PATWT,NO: VW) r .I T' TECHNOLOGIES Maintenance Cleaning The CDS system should be inspected at regular intervals and Cleaning of a CDS systems should be done during dry weather maintained when necessary to ensure optimum performance. conditions when no flow is entering the system.The use of a The rate at which the system collects pollutants will depend more vacuum truck is generally the most effective and convenient heavily on site activities than the size of the unit. For example, method of removing pollutants from the system. Simply remove unstable soils or heavy winter sanding will cause the grit chamber the manhole covers and insert the vacuum hose into the sump. to fill more quickly but regular sweeping of paved surfaces will The system should be completely drained down and the sump slow accumulation. fully evacuated of sediment.The area outside the screen should also be cleaned out if pollutant build-up exists in this area. Inspection In installations where the risk of petroleum spills is small, liquid Inspection is the key to effective maintenance and is easily contaminants may not accumulate as quickly as sediment. performed. Pollutant transport and deposition may vary from However,the system should be cleaned out immediately in year to year and regular inspections will help ensure that the the event of an oil or gasoline spill should be cleaned out system is cleaned out at the appropriate time. At a minimum, immediately. Motor oil and other hydrocarbons that accumulate inspections should be performed twice per year(e.g. spring on a more routine basis should be removed when an appreciable and fall) however more frequent inspections may be necessary layer has been captured.To remove these pollutants, it may in climates where winter sanding operations may lead to rapid be preferable to use absorbent pads since they are usually less accumulations, or in equipment washdown areas. Installations expensive to dispose than the oil/water emulsion that may be should also be inspected more frequently where excessive created by vacuuming the oily layer.Trash and debris can be amounts of trash are expected. netted out to separate it from the other pollutants. The screen The visual inspection should ascertain that the system should be power washed to ensure it is free of trash and debris. components are in working order and that there are no Manhole covers should be securely seated following cleaning blockages or obstructions in the inlet and separation screen. activities to prevent leakage of runoff into the system from above The inspection should also quantify the accumulation of and also to ensure that proper safety precautions have been hydrocarbons,trash, and sediment in the system. Measuring followed. Confined space entry procedures need to be followed pollutant accumulation can be done with a calibrated dipstick, if physical access is required. Disposal of all material removed tape measure or other measuring instrument. If absorbent from the CDS system should be done in accordance with local material is used for enhanced removal of hydrocarbons,the level regulations. In many jurisdictions, disposal of the sediments may of discoloration of the sorbent material should also be identified be handled in the same manner as the disposal of sediments during inspection. It is useful and often required as part of an removed from catch basins or deep sump manholes. operating permit to keep a record of each inspection. A simple form for doing so is provided. Access to the CDS unit is typically achieved through two manhole access covers. One opening allows for inspection and cleanout of the separation chamber(cylinder and screen)and isolated sump. The other allows for inspection and cleanout of sediment captured and retained outside the screen. For deep units, a single manhole access point would allows both sump cleanout and access outside the screen. The CDS system should be cleaned when the level of sediment has reached 75%of capacity in the isolated sump or when an appreciable level of hydrocarbons and trash has accumulated. If absorbent material is used, it should be replaced when significant discoloration has occurred. Performance will not be impacted until 100%of the sump capacity is exceeded howevers it is recommended that the system be cleaned prior to that ' 'r for easier removal of sediment. The level of sediment is easily } determined by measuring from finished grade down to the top of the sediment pile. To avoid underestimating the level of sediment in the chamber,the measuring device must be lowered - to the top of the sediment pile carefully. Particles at the top of the pile typically offer less resistance to the end of the rod than consolidated particles toward the bottom of the pile. Once this measurement is recorded, it should be compared to the as-built drawing for the unit to determine weather the height of the sediment pile off the bottom of the sump floor exceeds 75%of the total height of isolated sump. ,;� _ CDS Diameter Distance from Water Surface Sediment Model to Top of Sediment Pile Storage Capacity ft m ft m yd3 m3 1 1 1 1 • 1 i 1 1 � / 1 • • F � 1 • • 1 it 1 '1' 6�. ,- -.E,.y_ 'fir• -t. L.-:. t +.Lr . W �.... Support • Drawings and specifications are available at wvvw.contechstormwater.com. • Site-specific design support is available from our engineers. ©2010 CONTECH Stormwater Solutions CONTECH Construction Products Inc.provides site solutions for the civil engineering industry. CONTECH's portfolio includes bridges,drainage,sanitary sewer,stormwater and earth stabilization products.For information on other CONTECH division offerings,visit contech- cpi.com or call 800.338.1122 Nothing in this catalog should be construed as an expressed warranty or an implied warranty of merchantability or fitness for any particular purpose.See the CONTECH standard quotation or acknowledgement for applicable warranties and other terms and conditions of sale. The product(s)described may be protected by one or more of the following US patents: 5,322,629;5,624,576;5,707,527;5,759,415;5,788,848;5,985,157;6,027,639;6,350,374; 6,406.218;6,641,720;6,511,595;6,649,048;6,991,114;6,998,038;7,186,058;7,296,692; 7,297,266;7,517,450 related foreign patents or other patents pending. CDS Inspection • • CDS Model: Location: Water Floatable Describe Date depth to Layer Maintenance Maintenance Comments sediment' Thickness' Performed Personnel 1. The water depth to sediment is determined by taking two measurements with a stadia rod:one measurement from the manhole opening to the top of the sediment pile and the other from the manhole opening to the water surface. If the difference between these measurements is less than eighteen inches the system should be cleaned out Note:To avoid underestimating the volume of sediment in the chamber,the measuring device must be carefully lowered to the top of the sediment pile. For optimum performance,the system should be cleaned out when the floating hydrocarbon layer accumulates to an appreciable thickness. In the event of an oil spill,the system should be cleaned immediately. etts Sto UNIVERSITY OF MASSACHUSETTS Evalu t onsProject rrviwater AT AMHERST Water Resources Research Center (413)545-5532 Blaisdell House, UMass (413)545-2304 FAX 310 Hicks Way www.mastep.net Amherst, MA 01003 MASTED Technoloqy Review Technologv Name: CDS (Continuous Deflective Separator) - Contech Stormwater Solutions, Inc. Studies Reviewed: • Independent Review of CDS 2015 Product Evaluation, FB Environmental Associates, 2009. • NJCAT Technology Verification Addendum Report High Efficiency Continuous Deflective Separators CDS Technologies Inc. December 2004 • Continuous Deflection Separation (CDS) Unit For Sediment Control In Brevard County, Florida January, 2000 Date: 12/16/2009 Reviewer: Jerry Schoen Rating: 2 Brief rationale for rating: MASTEP rating is based primarily on FB Environmental 2009 laboratory study. This study generally followed NJDEP-recommended laboratory test protocols,with some exceptions: no evidence of a Quality Assurance Project Plan, little discussion of quality control, higher than recommended particle size distribution, limited range of influent sediment concentration, sediments analyzed by SSC method but not TSS. The Florida field study monitored 5 storm events and encountered sampling/equipment problems in four of them. The NJCAT lab study was conducted on a unit that was specially modified for testing in New Jersey, and is now being sold in NJ and NY. Other Comments: FB Environmental Associates study: • OK-110 sediment mix used. This is recommended by Maine DEP, but produces sediments somewhat larger than those recommended by New Jersey DEP. • Sediment analysis conducted with whole sample; essentially SSC method. SSC is generally regarded as more accurate than TSS method, but comparisons with other studies or products that use TSS data are problematic. • Full range of flows were tested. • Only one target sediment concentration was tested; average influent SSC was 313 mg/I, slightly outside of recommended 100-300 mg/I range. • Scour test was performed; system produced no scour at flows up to 1371/6 of capacity. N3CAT Study Expectations of sediment removal performance comparable to this study should be confined to units that contain the sediment weir and a 2400 micron screen. The study did not include a scour test. A particularly fine sediment mix (Sil-Col-Sil 106, pre-washed to remove all particles > 100 microns), which makes sediment removal more difficult. Higher removal efficiencies may be obtained if sediment particle size range is larger. Water Resources Research Center Page 1 University of Massachusetts—Amherst 12/16/2009 • A narrow range of influent sediment (164—203 mg/I, average 184),was tested but this is within the NJDEP-recommended 100-300 mg/I range. ■ TSS analysis appears to have been performed by a non-standardized method. ® No discussion of quality control. Brevard County FL study This study was performed before release of the TARP Tier II Protocols and does not conform to them. ® The study states that"testing under higher flow conditions would be desirable." • TSS, BOD, COD, pH, total phosphorus, and turbidity were monitored. Center For Energy Efficiency and Renevva-ble Energy Page 2 University of Massachusetts—Amherst February 11, 1999 Page 1 of 1 Project: 480 Suite 3 Arsenal Street �v Location: Watertown, MA C o NTECH' Prepared For: Brian Studer-RJ O'Connel &Associates, Inc. ENGINEERED SOLUTIONS Purpose: To calculate the water quality flow rate (WQF)over a given site area. In this situation the WQF is derived from the first 1.0"of runoff. Reference: Massachusetts Dept. of Environmental Protection Wetlands Program/United States Department of Agriculture Natural Resources Conservation Service TR-55 Manual Structure I Impv. I A tc tc WQV Given: Name acres (mile s2) min) (hr) (in) CDS-1 1.31 0.0020491 6.0 0.100 1.00 CDS-2 0.72 0.0011238 6.0 0.100 1.00 CDS-3 0.57 0.0008959 6.0 0.100 1.00 Procedure: Determine unit peak discharge using Figure 1 or 2. Figure 2 is in tabular form so is preferred. Using the tc, read the unit peak discharge (qu)from Figure 1 or Table in Figure 2. qu is expressed in the following units: cfs/mil/watershed inches (csm/in). structure Name qu (csm/in.) CDS-1 774.00 CDS-2 774.00 CDS-3 774.00 1. Compute Q Rate using the following equation: Q,_ (qu) (A) (WQV) where: Q,=flow fate associated with first 1.0"of runoff qu =the unit peak discharge, in csm/in. A= impervious surface drainage area (in square miles) WQV=water quality volume in watershed inches (1.0" in this case) Structure Name Q, cfs CDS-1 CDS-2 CDS-3 CDS ESTIMATED NET ANNUAL TSS REDUCTION 11111b`a BASED ON THE RATIONAL RAINFALL METHOD �s 480 SUITE 3 ARSENAL STREET C=.►:NTECK WATERTOWN, MA ENGINEERED SOLUTIONS for SYSTEM: CDS-1 Area 1.31 acres CDS Model Weighted C 0.90 2020-5 Tc 6 minutes CDS Treatment Capacity 2.2 cfs Rainfall Percent Cumulative Total Removal Incremental Intensity' Rainfall Rainfall Flowrate Treated Flowrate(cfs) Efficiencv, Removal (%) (in/hr) Volume' Volume (cfs) 0.02 10.2% 10.2% 0.02 0.02 96.5 9.8 0.04 9.6% 19.8% 0.05 0.05 95.8 9.2 0.06 9.4% 29.3% 0.07 0.07 95.0 9.0 0.08 7.7% 37.0% 0.09 0.09 94.3 7.3 0.10 8.6% 45.6% 0.12 0.12 93.6 8.0 0.12 6.3% 51.9% 0.14 0.14 92.8 5.8 0.14 4.7% 56.5% 0.17 0.17 92.1 4.3 0.16 4.6% 61.2% 0.19 0.19 91.4 4.2 0.18 3.5% 64.7% 0.21 0.21 90.6 3.2 0.20 4.3% 69.1% 0.24 0.24 89.9 3.9 0.25 8.0% 77.1% 0.29 0.29 88.1 7.0 0.30 5.6% 82.7% 0.35 0.35 86.3 4.8 0.35 4.4% 87.0% 0.41 0.41 84.4 3.7 0.40 2.5% 89.5% 0.47 0.47 82.6 2.1 0.45 2.5% 92.1% 0.53 0.53 80.8 2.0 0.50 1.4% 93.5% 0.59 0.59 79.0 1.1 0.75 5.0% 98.5% 0.88 0.88 69.8 3.5 1.00 1.0% 99.5% 1.18 1.18 60.7 0.6 1.50 0.0% 99.5% 1.77 1.77 42.5 0.0 2.00 0.0% 99.5% 2.36 2.20 27.1 0.0 3.00 0.5% 100.0% 3.54 2.20 18.1 0.1 89.9 Removal Efficiency Adjustment2= 6.5% Predicted %Annual Rainfall Treated = 93.4% Predicted Net Annual Load Removal Efficiency= 83.4% 1 - Based on 10 years of hourly precipitation data from NCDC Station 770, Boston WSFO AP, Suffolk County, MA 2 - Reduction due to use of 60-minute data for a site that has a time of concentration less than 30-minutes. CDS ESTIMATED NET ANNUAL TSS REDUCTION 11111b`a BASED ON THE RATIONAL RAINFALL METHOD �s 480 SUITE 3 ARSENAL STREET C=.►:NTECK WATERTOWN, MA ENGINEERED SOLUTIONS for SYSTEM: CDS-2 Area 0.72 acres CDS Model Weighted C 0.90 2015-4 Tc 6 minutes CDS Treatment Capacity 1.4 cfs Rainfall Percent Cumulative Total Removal Incremental Intensity' Rainfall Rainfall Flowrate Treated Flowrate(cfs) Efficiencv, Removal (%) (in/hr) Volume' Volume (cfs) 0.02 10.2% 10.2% 0.01 0.01 96.6 9.8 0.04 9.6% 19.8% 0.03 0.03 96.0 9.3 0.06 9.4% 29.3% 0.04 0.04 95.3 9.0 0.08 7.7% 37.0% 0.05 0.05 94.7 7.3 0.10 8.6% 45.6% 0.06 0.06 94.1 8.1 0.12 6.3% 51.9% 0.08 0.08 93.4 5.9 0.14 4.7% 56.5% 0.09 0.09 92.8 4.3 0.16 4.6% 61.2% 0.10 0.10 92.2 4.3 0.18 3.5% 64.7% 0.12 0.12 91.5 3.2 0.20 4.3% 69.1% 0.13 0.13 90.9 3.9 0.25 8.0% 77.1% 0.16 0.16 89.3 7.1 0.30 5.6% 82.7% 0.19 0.19 87.8 4.9 0.35 4.4% 87.0% 0.23 0.23 86.2 3.8 0.40 2.5% 89.5% 0.26 0.26 84.6 2.1 0.45 2.5% 92.1% 0.29 0.29 83.0 2.1 0.50 1.4% 93.5% 0.32 0.32 81.5 1.1 0.75 5.0% 98.5% 0.49 0.49 73.6 3.7 1.00 1.0% 99.5% 0.65 0.65 65.7 0.7 1.50 0.0% 99.5% 0.97 0.97 49.9 0.0 2.00 0.0% 99.5% 1.30 1.30 34.2 0.0 3.00 0.5% 100.0% 1.94 1.40 21.0 0.1 90.8 Removal Efficiency Adjustment2= 6.5% Predicted %Annual Rainfall Treated = 93.4% Predicted Net Annual Load Removal Efficiency= 84.4% 1 - Based on 10 years of hourly precipitation data from NCDC Station 770, Boston WSFO AP, Suffolk County, MA 2 - Reduction due to use of 60-minute data for a site that has a time of concentration less than 30-minutes. CDS ESTIMATED NET ANNUAL TSS REDUCTION 11111b`a BASED ON THE RATIONAL RAINFALL METHOD �s 480 SUITE 3 ARSENAL STREET C=.►:NTECK WATERTOWN, MA ENGINEERED SOLUTIONS for SYSTEM: CDS-3 Area 0.57 acres CDS Model Weighted C 0.90 2015-4 Tc 6 minutes CDS Treatment Capacity 1.4 cfs Rainfall Percent Cumulative Total Removal Incremental Intensity' Rainfall Rainfall Flowrate Treated Flowrate(cfs) Efficiencv, Removal (%) (in/hr) Volume' Volume (cfs) 0.02 10.2% 10.2% 0.01 0.01 96.7 9.8 0.04 9.6% 19.8% 0.02 0.02 96.2 9.3 0.06 9.4% 29.3% 0.03 0.03 95.7 9.0 0.08 7.7% 37.0% 0.04 0.04 95.2 7.4 0.10 8.6% 45.6% 0.05 0.05 94.7 8.1 0.12 6.3% 51.9% 0.06 0.06 94.2 5.9 0.14 4.7% 56.5% 0.07 0.07 93.7 4.4 0.16 4.6% 61.2% 0.08 0.08 93.2 4.3 0.18 3.5% 64.7% 0.09 0.09 92.7 3.3 0.20 4.3% 69.1% 0.10 0.10 92.2 4.0 0.25 8.0% 77.1% 0.13 0.13 91.0 7.3 0.30 5.6% 82.7% 0.15 0.15 89.7 5.0 0.35 4.4% 87.0% 0.18 0.18 88.5 3.9 0.40 2.5% 89.5% 0.21 0.21 87.2 2.2 0.45 2.5% 92.1% 0.23 0.23 86.0 2.2 0.50 1.4% 93.5% 0.26 0.26 84.7 1.2 0.75 5.0% 98.5% 0.38 0.38 78.5 4.0 1.00 1.0% 99.5% 0.51 0.51 72.3 0.7 1.50 0.0% 99.5% 0.77 0.77 59.8 0.0 2.00 0.0% 99.5% 1.03 1.03 47.3 0.0 3.00 0.5% 100.0% 1.54 1.40 26.5 0.1 92.1 Removal Efficiency Adjustment2= 6.5% Predicted %Annual Rainfall Treated = 93.5% Predicted Net Annual Load Removal Efficiency= 85.6% 1 - Based on 10 years of hourly precipitation data from NCDC Station 770, Boston WSFO AP, Suffolk County, MA 2 - Reduction due to use of 60-minute data for a site that has a time of concentration less than 30-minutes. Memorandum awn Date: January 29, 2015 Recipient: Boylston Properties Company, Inc. Jeffrey Heidelberg Copy To: RI O'Connell & Associates, Inc. - Roy Smith Sender: Benjamin E. Downing, Jonathan W. Patch, P.E. Project: 488 Arsenal Street; Watertown, MA Project No: 5722.2.00 Subject: Design Permeability Rates During the recent supplemental subsurface exploration program, three (3) constant head, in-situ permeability tests were performed at the site. The tests were performed approximately 4 feet above the groundwater level within borings B-203, B-205 and B-206. The permeability tests at borings B-203 and B-206 were performed in the natural outwash deposit and the test at boring B-205 was performed in the fill material. The results of the individual in-situ permeability tests are summarized below. Constant Head Borehole Permeabilitv Test Summary Borehole Test Depth Soil Strata Head Flow Rate, q Permeability, k (ft) (ft) (cm3/s) (cm/s) (in/hr) B-203 15.0 Outwash 2.5 1.50x102 4.70x10-2 66.60 B-205 5.0 Fill 5 7.00x102 1.10x10-' 155.91 B-206 15.0 Outwash 2.5 9.01x10-2 2.82x10-5 0.04 The fill material within boring B-205 was observed to contain bricks and other construction debris. It is anticipated that there are voids within the fill material as a result. The high permeability observed during the in-situ test is considered to be a result of the presumed voids in the fill and not attributable to the actual soil permeability. A fourth in-situ permeability test was planned for boring B-202. However, the boring encountered a large void at a depth of about 14 feet below ground surface. An in-situ permeability test was not run at this location due to the void because the test would likely not have been representative of the design conditions. Furthermore, based on the laboratory grain-size distributions of soil samples obtained from the borings, the soil texture class was determined using the USDA textural triangle. The soil texture class was then compared to the chart of Rawls Infiltration Rates to determine design permeability values. The Rawls Infiltration Rates are based on research performed GEOTECHNICALAND GEOENVIRONMENTAL ENGINEERS 2269 Massachusetts Avenue Cambridge, Massachusetts 02140 Page 1 of 2 (617) 868-1420 g Memorandum awn by Rawls, Brakensiek and Sexton in 1982 which used laboratory permeability testing to develop a relationship between texture class and saturated permeability. McPhail also estimated the coefficient of permeability of the fill material and outwash deposit based on the laboratory grain-size distributions using the Kozeny-Carmen formula. This empirical method involves the use of additional parameters such as void ratio and particle shape, which are estimated from the boring data and the representative soil sample grain-size analyses. The Rawls rates for the various soil types were found to be similar to the results of the Kozeny-Carman analyses. Based on discussions with RI O'Connell & Associates, Inc., the project site civil engineer, there are four (4) potential areas for stormwater infiltration systems. The following table contains our recommended design permeability rates for the four proposed areas. Desian Permeabilitv Rates Site Location Texture Class * Design Permeability (in/hr) (cm/s) East Loamy Sand 2.41 1.7 x10-3 Southeast Sand 8.27 5.9 x10-3 Southwest Loamy Sand 2.41 1.7 x10-3 West Loam 0.52 3.7 x10-4 * Based on USDA Textural Triangle It should be noted the existing fill material and outwash deposit are heterogeneous in composition and variable in density, thus it is anticipated that the coefficient of permeability may be highly variable and the results of our permeability testing may not be representative of the entire deposit. We did not observe groundwater or indications of a seasonal high groundwater level in the test pits that were performed at the site. However, we did encounter groundwater in the borings and we have installed several groundwater observation wells across the site. Based on the groundwater observation well data, the following are approximate estimated seasonal high groundwater level (ESHGW) values in the vicinity of each of the proposed stormwater infiltration system locations: • East, near boring B-5(OW) - Elevation +19 • Southeast, near boring B-8(OW) - Elevation +18 • Southwest, near boring B-9(OW) - Elevation +26 • West, near boring B-3(OW) - Elevation +19 We trust that the above is sufficient for your present requirements. Should you have any questions concerning the recommendations presented herein, please do not hesitate to contact us F:\WP5\JOBS\5722\5722_Permeability_Testing_Summary_revl_012915_.docx GEOTECHNICALAND GEOENVIRONMENTAL ENGINEERS 2269 Massachusetts Avenue Cambridge, Massachusetts 02140 Page 2 of 2 (617) 868-1420 g l#Ykt c P ccaaec c '3sb 4�` x x_v"v o<' cc s _ ,nr� r5 ;,a a;v VGGa � Y\� ae rs ` A. / :� TITLE TO AND RIGHTS BUSINESS THE PUBLI AND OTHERS �� / 6ic \t �=W NI -HOLS AVENUE � j 6 .1 \ INDUSTRIAL-2�4 \\ - - " - - - = e sr BIT CONC.i /BIT CONC T _ �safi 56 - RES BOOK i]i2]PAGE 4N a ) R- 45- ST ISO i44 RESER iATION 0%RIGHT D�rz ) k I (OEE B OK 1]i ]/AGE 40 sFO E S E LI -rss sizaiar�.. c a I.C lr' 4.]' a -�-\ r]M' v-j" 4 \h J M. 4 GRAS F IFJ- 3- 'CLF♦Z 187_42 F',�,, 5 CO S_ _'=E-----4---_----- qs_--__---me asR - _ - _ /cv'S 9'Siz'f _ P� �\ a - - �1 -Z- 42 4o- - �a \ ---_ 6 -_.-_----I `�'� -1 1_ ,5' 3. .-.=-4% PINEIHEES- - J � I,]6 ETREES ------ --�`- -=4s y. "'°--`_ffi'J°_ �,� „«� �r 35 ----i 9j 1 he '� LOT 3� seDn \ 1 \PINE TREES 4]---r-----� -1 '� �� NJ \ -w]_�a �- - bc�_ as.] as., __--_-_ y -f� END ARMENF �� / / 43 w 1 L --- .as 4i,s-- -Z'__-_ - I =- / /F T� \ CULTURAL 46 ¢, a 45 ---- -- �Ji ___ �_�---__ _ ,P] (ORMER O �y.� u -44----_--__-__ _ ____ - I _ IrTREET LINE .0 ASSOCWTION ^ �,Q�u -42/ a \ 41�- ----------- ----- - =S'AA3�5----{�a642- .� r40 --' ---- 1PASS_ I �� T�ECRUryL' 1 ,h 21 B tl & BB 5 -- J]. 4 1- "�B�-�4r BBB S6 /A m 41/ / % / J6 SPACES I 6 POSED'r l ) \ ON-S/L :8:936c/- -ems SPACES 3$.fiiec } _a,0 5 2`P` I eoRwc w'=n afi6 I 3a o AasS 3a.65 ow s/ "3ss6 aze err-.. I wcu /9z' I _xi - 5].EI.=3] "A Q 1�,1\ 6 SPACES I i SPACE 2 SPACES I IS SPACES \\ a ram' '' �,.3i�. Bic 3B 3B22W �''R S 87.57'07"E 1 1,u -- B I (ow) e§�P 1 I \ a3 76.59' 1+y'i 1 I , Ir.cG c ae s n ee�1 SPACE„ I SPACE I v �`� G,�p 3 `ry�0 Gee e a GRASS 90] / O h ✓ / I y na 5 r M&S -� 40- J M&%�� ,fin/�.. .. I p [�1, 4 LOT 2A ///40 I OL PROVE RIN&r Z / 2�a 180.2'BO 1 rgC Z ?�mm I CAUSES CONNECTIOI \TBM L by �5`v h P9a]r�< I Er,oSD � i -\'---- —a a 4O�P BACK 0.,' /coNc. 5s.s TOWER wr I ' o ; APPROXIMATE LIMITS LF ' SECRUIP' CONC ` CAMERA >.'GOL _ m / o OF PROF05ED Rw PARKING STRUCTURE 4 = 4 / v a 4 SIGN ON GATE I , IILDING nEIGNT=26'3 (WATER ONE) OOFNOT LANE BLOCK) m / I DECLARATION OF EASEMENTS /- I ' ASSESSORS PAF `---------L� AND MAINTENANCE OBLIGATIONS I SPACE m 1 r\ (DEED BOOK 34045 PAGE 591) m, 1 / METAL CONTAINER • •1 \ i a= ?CA = 374,304 SQ. FT. M r e z 6NWry P� 6 ON CONC PAO x / , x 2 -------- ©= 8.593 ACRES I P 6 G3; a�� LOT 28 e I ° n o s m s I 374,003 SQ. FT REC. y E 6K. \r� I � I I as(owl z�5 ° � ` / E Ly AT&T CNR ORATION u� �J a OL - I (� r7R� Q�'RF.S I\LC.) METAL II R� �/m I � g � - h I a z M 8 I � //O i I CON PAD. ] �P 0eh ^ .���"> A" METAL RACKS 1[ 04 PA \\\ ', d I----------- TP 3 ON CONC. 0 �, G 8 1 (FOR UTILITY POLE STOPAGE)\ p1 . e N 5 I I BIT conc- I m A�h"I`hS / \\ 1 u BORIN A �m WELL Y3 D U �" L-39.6 B-2b6 I I 2� 02 ��. 1 5PAV a I -, TF I J OKI NG 1 78.00' I e� '°� APPROXIMATE LIMITS '-( ) v B-105 S 89*0003 M i I 41 `^-i _ n S \� OF SUBJECT SITE I-L- IL/LJ� / TOW26,6� I 3]6 fix" - (DRAIN LINE&OVERHEAD WIRE) Bai- 8 I 1 � - ( 03 ®DECLARATION OF EASEMENTS Tea / ]]D AND MAINTENANCE OBLIGATIONS (�,�� (DEED BOOK 34045 PAGE 591) r Ri=J1.J --- wzse6 ===— -203 �' \o) 12w �o " - �------- aR ► �RD �� � a R=35. 15 '5.27 o� o u`° APPROXIMATE LIMITS OF _ -rzv�_ .s _ h _ FPOP05ED OFFICE BUILDING - - L3J.w°ss 1 �i ' + // REG� II J 1 h� �—32. 1 � cam, \4 E Zawm E I 9 SPACES / \ U \ BORINGS U ; ro 6.65 h WELL 5 ` ' v v 6 5.0] 2 9. 1 4 +\ I \ 12 29.14' C � 0 o m V PROPOSED� ^ (DRAIN LINES) O-. \ WE RING / 6 m n� n ®DECORATION OF EASEMENTS cri p AND MAINTENANCE OBLIGATIONS `D' „n i u \ " �'� m m \ ----- --- (DEED BOOK 34045 PAGE 591) ``kW o ro ' ro �.ua DETAIL - \\ ro'� u PE6 _F a20 �notio 0 GRAPHIC SCALE LEGEND APPROXIMATE LOCATION OF BORING PERFORMED BY TECHNICAL DRILLING l SERVICES,INC.(TD5)OF STERLING,MA ON APRIL I G AND 17,201 4 FOR }+,c 0,`°a � g91 \9�"� McPHAIL ASSOCIATES,LLC 488 ARSENAL STREET m ABANDONED UTILITY AND STORM DRAIN EASEMENT 9( o OW B- APPROXIMATE LOCATION OF BORING PERFORMED BY TECHNICAL DRILLING SERVICES,INC. DS OF STERLING,MA ON MAY I G,201 4 FOR McFHAIL WATERTOWN MASSACHUSETTS A550CIATE5,LLC SUBSURFACE EXPLORATION PLAN / ,DEED BGD✓roax,�ncL r;_ °� psi //ii/ IC,\ - APPROXIMATE LOCATION OF BORING PERFORMED BY CARR-DEE CORP.DURING THE \ ` 3'64s�i ;e e° a�aP` 1 FOR PERIOD OF DECEMBER 19 THROUGH 23,2014 FOR McPHAIL ASSOCIATES,LLC � w unuYESEMENr oPas e+ 6 / /}3M1/ / ohs ° BOYL`JTON PROPERTIE`J COMPANY, INC. (DEED BOOK 141s1 BORr c .%`S31 / / 1 Bo s% / - APPROXIMATE LOCATION OF TEST PIT PERFORMED BY MATTUCHIO CONSTRUCTION \ PACE 19 6 ) _ _ _ Ao,r/ dt }h a',� / CO.,INC.ON DECEMBER 22,2014 FOR McPHAIL ASSOCIATES,LLC Geotechnical and BY a$ 9 ati' " U% G Nam,/ yGES .,�;q Geoenvironmental Engineers McPHAIL ASSOCIATES, LLC 1 ti A 50" E geeP - 2269 Massachusetts Avenue eG a 0.`l� _ }/6 ry,oT'S's° �t RERERENCE: THI5 PLAN WA5 PREPARED FROM A 40-5CALE PRELIMINARY DRAWING ENTITLED Cambridge, MA 02140 P °ql "ALTA/ACSM LAND TITLE SURVEY"DATED APRIL 14,201 4 BY FELDMAND LAND SURVEYORS 6 1 7/861 423 (F ep�5 Date: DECEMBER D 2014 IDwn: F.G P. I Chkd' B.E. . Scale: I"=40' 617/868-1423 (Fax) www.mcphoilgeo.com Project No: 5722 FIGURE 2 NORTHEAST REGION ` Engineering Design Assistance Kit ti (DAKit) v05b- NE f 1 [ te ^a- rfa � I Bioretention Systems +� A Growing Idea in Stormwater Filtration rl ` . 1 C%,do-NTECH' ENGINEERED SOLUTIONS Filterra° Stormwater Bioretention Filtration System For more information please call 800-338-1122 or visit www.ContechES.com. Reproduction of these detail drawings is permitted for use only in site plans or contract documents for eventual supply by Americast or its authorized dealer. Other uses are prohibited and may infringe copyright or patent protection laws. Copyright C 2014 by Filterre Bioretention Systems a Division of Americast. 2 www.filterra.com 6) filteffa Bioretention Systems Introduction and Scope of this Document At federal, state and local levels, stormwater management is increasingly important.Americast's Filterre units can help developers comply with NPDES legislation by removing pollutants,using a small eff cient natural system that is both cost-effective and reliable. This document is compiled to assist engineers in the proper design for the best results where Filterre is used for stormwater quality management. We want your project to be successful and it is important to this success that you follow guidelines contained herein. Please review the essential reading section. It is essential to: • Adhere to the Design Guidelines. • Size the Filterra®unit correctly, using the regional Sizing Table/. • Add Flowline detail, Gutter detail and Plan Notes to your plans • Complete the Project Information Form& submit with plans to Americast for review before permitting. THIS REVIEW IS MANDATORY for warranty to apply and helps ensure that each Filterra® system operates eff ciently to maximize performance and minimize maintenance. Other documents available on request include: Technical Whitepaper Scientif c paper more fully explaining processes occurring within the system Filterra Product Performance Data Summary Data sheet providing the latest facts available Third Parry Data Data presented by independent parties Letters of BMP Approval by various Agencies Copies of off cial approvals where available Installation, Operation&Maintenance Manual Owner's manual presenting technical and operational details. 3 www.filterra.com 6) filterra Table of Contents Bioretention Systems Introduction and Scope of this Document...................................................................................3 A. Essential Reading - Filterra® Overview Filterra® Overview...........................................................................................................................6 Design Guidelines for using Filterra®..........................................................................................7 Items Considered in Filterra®Plan Reviews....................................................................................8 Filterra®Project Information Form-IMPORTANT.......................................................................9 Table 1:Filterra Quick Sizing Table........................................................................................10 Guideline GUI-A: Filterra Grading& Gutter Flow............................................................11 Guideline GU2:Filterra Avoid Head-On Gutter Flow...........................................................12 Guideline GU3:Filterra Parking Lot Corners........................................................................13 B. Filterra® Plans, Placement & Grading Scenario PLGI:Filterra®Typical Parking Lot Applications..................................................15 Scenario PLG2:Filterra®Parking Lot Island Applications....................................................16 ScenarioPLG3:Filterra®Parking Lot Corner Applications...................................................17 Drawing FTINF-2:Precast Filterra®for Infiltration Applications.........................................18 Drawing FTSWL-1:Precast Filterra® Typical Swale Configuration......................................19 Drawing FTSC-2: Typical Filterra®Sidewalk Configuration.................................................20 Drawing FTRDF-1:Filterra®Roof Drain Flume Application................................................21 C. Standard Filterra®Detail Drawings & Filterra Plan Notes Drawing FLP-2:Filterra®Typical Flowline Relationship......................................................23 Drawing CGT-6:Filterra® Throat Opening& Gutter or Flume Detail..................................24 Filterra® Standard Plan Notes........................................................................................................25 Drawing FTNL-3:Precast Filterra® Unit Narrow Length Configuration..............................27 Drawing FTST-3: Precast Filterra® Unit Standard Configuration.........................................28 Drawing FTNW-3: Precast Filterra® Unit Narrow Width Configuration...............................29 Drawing FTIRR-2:Filterra®Irrigation Planning Layout.......................................................30 D. Filterra® Techinical Section Americast Filterra®Product Weights and Lifting Details..............................................................32 Drawing FTOPC-2: Filterra® Precast Box Wall at Outfall Pipe Connection........................33 Filterra® Piping Technical Details.................................................................................................34 Drawing DPI: Filterra® Precast Box Wall at Outfall Pipe Connection..................................34 Table 3: Filterra® Flow Rates & Pipe Details.........................................................................34 Filterra® Modified Options: Recessed Tops................................................................................35 Common Filterra® Placements......................................................................................................36 Filterra®Plant Selections................................................................................................................3 7 Filterra® Schematic...................................................................................................................3 8 4 4 www.filterra.com G- ) filteffa Bioretention Systems Section A Essential Reading - Filterra° Overview Important! Please remember to complete and send the Project Information Form to Filterra® with plans for evaluation. This review is mandatory as proper placement ensures optimum performance and validates the product warranty. Toll Free: (866)349-3458 Fax: (804)798-8400 support@filterra.com 5 www.filterra.com 6) filteffa Filterra° Overview Bioretention Systems Stormwater Bioretention Filtration System Save valuable space with small footprint : i for urban sites �,.. ' Improve BMP aesthetics with attractive trees or shrubs Reduce lifetime cost with safer and less expensive maintenance Remove Pollutants and Combly with NPDES Filterre is well-suited for the ultra-urban environment with high removal eff ciencies for many pollutants such as petroleum, heavy metals,phosphorus, nitrogen, TSS and bacteria. Filterre is similar in concept to bioretention in its function and applications, with the major distinction that Filterre has been optimized for high volume/f ow treatment and high pollutant removal. It takes up little space (often 0.33% Filter Surface Area/Drainage Area) and may be used on highly developed sites such as landscaped areas, green space,parking lots and streetscapes. Filterre is exceedingly adaptable and is the urban solution for Low Impact Development. Stormwater f ows through a specially designed f)ter media mixture contained in a landscaped concrete container. The f)ter media captures and immobilizes pollutants; those pollutants are then decomposed, volatilized and incorporated into the biomass of the Filterra® system's micro/macro fauna and f ora. Stormwater runoff f ows through the media and into an underdrain system at the bottom of the container, where the treated water is discharged. Higher f ows bypass the Filterra®via a downstream inlet structure, curb cut or other appropriate relief. Expected Average Pollutant Removal Rates (Ranges Varving with Particle Size. Pollutant Loading and Site Conditions) TSS Removal 85% Phosphorous Removal 60% - 70% Nitrogen Removal 43% Heavy Metal Removal 33% - 82% Fecal Coliform 57% - 76% Predicted Oil & Grease > 85% * Standard Blend 6 www.filterra.com 6) fi [teffa Design Guidelines for Using Filterra" Bioretention Systems 1. Do not place in a sump condition. The Filterra® cannot be used as a stand alone inlet—it will need effective bypass during higher intensity rainfall events. Plans MUST show Filterra®Top Curb (TC) and Flow Line (FL) spot elevations and also bypass TC (where applicable) and bypass FL spot elevations. The Filterra®TC and FL elevations MUST be higher than the bypass TC and FL elevations for effective bypass. Use Drawing FLP-2 as a detail on the project plans. 2. For proper trash collection ensure a minimum 4" and maximum 6"Filterra®throat opening depth and use Drawing CGT-04 as a detail on the project plans. 3. Do not direct surface f ow to the Filterra®in a"head-on" conf guration. Refer to Guidelines GUI-A and GU2 for grading design that encourages f ow to enter a Filterra® in a cross linear f ow—left-to-right or right to-left in the gutter in front of the throat, as per a wet curb which prevents system damage. During extreme storm events the excess f ow should continue past the Filterra®to a bypass inlet or other means of relief. Guideline GU3, Parking Lot Corners, shows common situations. 4. To calculate which size Filterra®is required,use Table 1, Filterra® Quick Sizing Table, appropriate to the project's geographical region and target treatment regime. The entire contributing drainage area to the Filterra® should be considered and the minimum allowable C factors noted. The maximum contributing drainage area will vary with site conditions. For further information relating to sizing,please contact Filterra. 5. To ensure correct installation, include the Standard Filterra®Plan Notes on your Filterra® detail project sheet, as well as detailed drawings FLP-2 and CGT-4. 6. Positive drainage of each Filterra®unit's eff uent treatment pipe is required to prevent free standing water from accumulating in the system or underdrain. This could occur due to tidal inf uences or improper connection of Filterra's eff uent pipe to a bypass structure or other outfall. 7. Send plans and the completed Filterra®Project Information Form to Americast for Filterra®placement review. Plan sheets should include grading, drainage areas, stormwater schedules or prof les, landscape sheets and Filterra® detail sheets. THIS REVIEW IS MANDATORY for warranty to apply and helps ensure that each Filterra® system operates eff ciently to maximize performance and minimize maintenance. Our staff also looks for value engineering opportunities. Methods of sending information for review are as follows: E-mail: support@f lterra.com, or upload to ftp site Mail or other: AutoCAD or PDF f les Filterra Review Fax: (804) 798-8400 11352 Virginia Precast Road Toll Free: (866) 349-3458 7 Ashland,VA 23005 www.filterra.com 0 filterra Bioretention Systems Items Considered in Americast's Filterra° Plan Reviews Following is a summary list of the items Americast considers during plan review. Plan sheets should include grading, drainage areas, stormwater schedules or prof les, landscape sheets and Filterra® details. Notes • Filterra® Structure Label or Identif cation Number • Planned Filterra®Box Size • Filterra® Contributing Drainage Area(not the bypass inlet Drainage Area) • The C Factor for each individual Filterra®drainage area Checks • The planned Filterra®box size meets project's regional sizing specif cation • Spot elevations (Top Curb & Flow Line) for Filterra®and bypass (TC &FL) • The Filterra® spot elevations (TC & FL) are higher than bypass spot elevations • The grading design encourages cross linear f ow and not head-on f ow • Filterra® invert elevations are shown(3.5'below TC) • Filterra® eff uent treatment pipe invert elevations are higher than bypass structure or other out fall invert elevations • The Filterra®outlet drain pipe is sized correctly • The outlet drain pipe exits perpendicular to the Filterra®wall • For any conf icting structures such as storm drain pipes below Filterra® • For most eff cient placement of Filterra®units • Plans include Filterra®details listed below: FLP-2:Filterra® Typical Flow Line and Outlet Pipe Relationship CGT-04: Filterra® Throat Opening and Gutter or Flume Detail Filterra®Standard Plan Notes (2 pages) s www.filterra.com PLEASE PRINT AND FAX OR EMAIL THIS FORM 6/07-v01-MidAtl. Filterra® Project Information Form Complete&send to Americast by email,fax or mail. —0 Address: 11352 Virginia Precast Raod Toll Free: (866)349-3458 Fax: (804)798-8400 fl Ite f ra Ashland,VA 23005 Email: support@filterra.com i4[imn•me ldt m S10fm'x Ja FIlCAm. (Project Information I Engineering Contact Information Project Name/Number: Engineering Firm: Current Date: Regulatory Municipality and State(City,County,etc.): Contact: Phone: Target Treatment Rate: Email: Fax: Filterra®Details(Email,mail or fax plans to Americast-Acceptable formats are AutoCAD or pdf) Plans sheets should include(1)cover,(2)grading,(3)drainage areas,(4)stormwater schedules or profile,(5)landscaping&(6)Filterra®details. Filterra Structure# Filterra Size(ID ft) Throat L x W Filterra Drainage Area Acres Runoff Coefficient C Factor Filterra Spot Elevation TC FL INV OUT Bypass Spot Elevation TC FL Bypass or Effluent INV IN Modified Structure Y/N? Road Slope % TC=Top Curb,FL=Flow Line FLP Detail on plans(Y/N)� I CGT Detail on plans(Y/N) FT Plan Notes shown(Y/N)� 9 ■ EI i teffa Bioretention Systems Table 1: Filterra° Quick Sizing Table (Northeast Region - v04) Available Filterra®Box Sizes Recommended Commercial Outlet Pipe (feet) Contributing Drainage Area (acres) where C = 0.85 4x6 or 6x4 up to 0.32 4" SDR-35 PVC 4x8 or 8x4 0.33 to 0.42 4" SDR-35 PVC Standard 6x6 0.43 to 0.47 4" SDR-35 PVC 6x8 or 8x6 or 4x12 or 12x4 0.48 to 0.64 4" SDR-35 PVC 6x10 or 10x6 0.65 to 0.79 6" SDR-35 PVC 6x12 or 12x6 0.80 to 0.95 6" SDR-35 PVC 7x13 or 13x7 0.96 to 1.20 6" SDR-35 PVC Recommended Residential Available Filterra° Box Sizes Contributing Drainage Area Outlet Pipe (feet) (acres)where C = 0.50 4x6 or 6x4 up to 0.54 4" SDR-35 PVC 4x8 or 8x4 0.56 to 0.72 4" SDR-35 PVC Standard 6x6 0.73 to 0.80 4" SDR-35 PVC 6x8 or 8x6 or 4x12 or 12x4 0.81 to 1.08 4" SDR-35 PVC 6x10 or 10x6 1.09 to 1.34 6" SDR-35 PVC 6x12 or 12x6 1.35 to 1.62 6" SDR-35 PVC 7x13 or 13x7 1.63 to 2.04 6" SDR-35 PVC Notes: 1. All boxes are a standard 3.5 feet depth (INV to TC) 2. A standard SDR-35 PVC pipe coupling is cast into the wall for easy connection to discharge drain 3. Dimensions shown are internal. Please add V to each external dimensions(using 6"walls) 4. In line with TR55 data,for Commercial Developments a minimum (runoff coefficient)C factor of 0.85 is recommended. For Residential Developments, use of C factors less than 0.5 require individual site review by Filterra. 5. Please ask for Sizing Tables for other target treatment goals, e.g. 0.3 in/hr 6. This sizing table is valid for MA(treating 90%of annual runoff)and typical for the Northeast region. 10 www.filterra.com GRADING AND GUTTER FLOW GRADING AND CURB AND CURB (TYP) GUTTER SHOULD BE SUCH THAT GUTTER FLOW APPROACHES THE FILTERRA GUTTER FLOW FROM ONE SIDE OF THE TO BYPASS THROAT AND FLOWS AWAY FROM THE FILTERRA ON PAVED THE OPPOSITE SIDE DURING AREA EXTREME STORM EVENTS. DESIGN OR INSTALLATION FILTERRA SUCH THAT FLOW APPROACHES FROM BOTH GUTTER FLOW SIDES WILL RESULT IN SITE FROM CONTRIBUTING MAINTENANCE ISSUES AND DRAINAGE AREA VOID MANUFACTURER'S GUTTER FLOW MAINTENANCE PROGRAM AND WARRANTY. PAVED PAVED LOW LOW AREA POINT POINT AREA CURB (TYP) CURB (TYP f [ � f f f O O BYPASS , BYPASS INLET INLET FILTERRA FILTERRA INCORRECT CORRECT MODIFICATIONS OF DRAWINGS ARE ONLY PERMITTED BY WRITTEN AUTHORIZATION FROM FILTERRA DATE: 03-03-05 DWG: GU 1-A FILTERRA® GUIDELINES fira�tBf ® GRADING AND GUTTER FLOW US PAT 6,277,274 Copyright©2007 by Americast AND 6,569,321 11 AVOID "HEAD-ON" GUTTER FLOW FLOW FROM THE ADJACENT GUTTER HITS THE FILTERRA "HEAD-ON". THIS CAN CURB (TYP) CAUSE SYSTEM DAMAGE -� (MEDIA EROSION OR SUSPENSION). REGARDLESS FILTERRA OF WHETHER BYPASS IS 1 PAVED PROVIDED THIS IS A AREA PROBLEM SCENARIO. GUTTER FLOW SHOULD FLOW APPROACH THE FILTERRA PARALLEL TO THE THROAT SO THAT WATER FLOWS IN A LINEAR PATTERN IN FRONT OF THE THROAT. DURING EXTREME STORM EVENTS, EXCESS WATER SHOULD CONTINUE TO FLOW IN FRONT OF THE FILTERRA TO A SS PROBLEM OTHERBYP REL EF. INLET OR r CURB (TYP) CURB (TYP) FILTERRA (FILTERRA B CURB ET PAVED (TYP) —f S PAVED Lpyy AREAAREA POINT LOW LOW POINT PAVED AREA OPOINT ��L CURBINLET — O 7 W BYPASSFILTERRA — BYPASS— rEll INLET L CONCRETE OR PAVED FLUME POSSIBLE SOLUTIONS MODIFICATIONS OF DRAWINGS ARE ONLY PERMITTED BY WRITTEN AUTHORIZATION FROM FILTERRA DATE: 12-22-04 I DWG: GU2 FILTERRA® GUIDELINES ��,— ,_,Il[]�I frp�o AVOID "HEAD-ON" lul GUTTTER FLOW US PAT 6,277,274 Copyright©2007byAmericast AND 6,569,321 12 PARKING LOT CORNERS CURB (TYP) CURB (TYP) J STORM STORM O � DRAIN PAVED DRAIN PAVED INLET AREA O � INLET AREA FLOW FLOW B B INTENDED �� INTENDED DRAINAGE DRAINAGE AREA AREA ELEV 'A' MUST BE FILTERRA ® REQUIRED HIGHER THAN ELEV 'B' �� CROSS IN ORDER TO ACHIEVE REQUIRED LINEAR A FLOW THE NECESSARY BYPASS r BYPASS FLOW r A FLOW ELEV 'A' MUST BE HIGHER THAN ELEV 'B' IN ORDER TO ACHIEVE THE FILTERRA — NECESSARY CROSS LINEAR FLOW TO BYPASS PLACEMENT PLACEMENT STORM STORM DRAIN PAVED DRAIN PAVED O � INLET AREA O � INLET AREA FILTERRA — — RESULTING CONTRIBUTING DRAINAGE AREA IS MOST LIKELY ONLY WHAT IS \ CAPTURED AND RETAINED ARROWS SHOW ® ! IN THE DEPTH OF THE PROBABLE CURB AND GUTTER SURFACE FLOW . — ., � ARROWS SHOW PROBABLE SURFACE FLOW B RESULTING J CONTRIBUTING FILTERRA DRAINAGE AREA PROBLEM PROBLEM STORVED DRAIN NM INLET &FILTERRA — CURB (TYP) ® AREA LOW POINT PAVED AREA STORM Q� \ DRAIN INLET PAVED AREALOW POINT 0/ LOW POINT ® M STORM \ DRAIN CURB ® INLET FILTERRA (TYP) (NP)FILTERRA FILTERRA CURB (TYP) MODIFICATIONS OF DRAWINGS ARE ONLY PERMITTED POSSIBLE PLACEMENT SOLUTIONS BY WRITTEN AUTHORIZATION FROM FILTERRA DATE: 12-14-04 I DWG: GU3 FILTERRA® GUIDELINES PARKING LOT CORNERS u loll US PAT 2 74 AND 6,569,321 7, Copyright©2007 by Americast 13 -6) ■ fl [teffa Bioretention Systems Section B Filterra° Plans, Placement & Grading Scenario Ideas to Ensure Maximum Eff ciency & Minimum Space Used Toll Free: (866)349-3458 Fax: (804)798-8400 support@filterra.com 14 www.filterra.com FILTERRA � LOW POINT m FILTERRA CURB INLET CURB INLET FILTERRA m LOW POINT FILTERRA LOW POINTS AT 2 SIDES FILTERRA FILTERRA CURB INLET F. . CURB INLET FILTERRA 2' FILTERRA LOW POINT LOW POINT LOW POINT LOW POINT FILTERRA FILTERRA CURB INLET �"�Lml 1 ( m L'� CURB INLET FILTERRA J ` FILTERRA LOW POINTS AT 4 CORNERS 4LTERRA CURB INLET �— FILTERRA LOW POINT ARROWS INDICATE DIRECTION OF SURFACE DRAINAGE FLOW LOW POINT —_ e — FILTERRA CURB INLET MODIFICATIONS OF DRAWINGS J ` FILTERRA ARE ONLY PERMITTED BY WRITTEN AUTHORIZATION LOW POINTS AT 2 CORNERS FROM FILTERRA DATE: 01 -03-05 I DWG: PLG1 FILTERRA® EXAMPLE SCENARIOS TYPICAL PARKING lul p copyrighto2oo7byAmericast LOT APPLICATIONS US PAT 6,277,274 AND 6,569,321 15 TO PAVED FILTERRA FLUME (SLOPED TOWARD BYPASS THROAT RELIEF AREA OPENING FILTERRA THROAT) 3 PRECAST 4" MIN LOWER o FILTERRA 6" MAX ELEVATION U` CONCRETE OR TOP SLAB CURB CURB CUT — PAVED FLUME FILTERRA PARKING LOT ISLAND UNIT \ . :.::;. CAST—IN—PLACE \ FLUME & GUTTER DOWEL THROAT . HIGHERN TO , PROVIDGUTTER E POSITIVE DRAINAGE ELEVATION CURB PRECAST �^ CURB CUT (TYP) FILTERRA +' TO THROAT OPENING BOX WALL g PAVED SECTION VIEW OF FILTERRA AREA THROAT AND FLUME ON—GRADE ISLAND IN OPEN PARKING LOT PAVED PAVED TO AREA FILTERRA UNIT AREA BYPASS' RELIEF 3 O CURB 3 u- (TYP) CURB CUT �t` FILTERRA UNIT CURB INLET — THROAT (LOW POINT) LOT PARKING (LOW 0 CONCRETE OR� PARKING LOT ISLAND � PAVED FLUME_ � CONCRETE OR CURB _/3 FLOW / PAVED FLUME CUT 3 CURB CUT J PAVED t` ® PAVED o AREA AREA 3 U- FILTERRA UNIT �vp p� CURB J F� (TYP) LOW POINT ISLAND ON—GRADE ISLAND AT SIDE OF PARKING LOT AT SIDE OF PARKING LOT MODIFICATIONS OF DRAWINGS ARE ONLY PERMITTED BY WRITTEN AUTHORIZATION FROM FILTERRA DATE: 01-03-05 DWG: PLG2 FILTERRA® EXAMPLE SCENARIOS ® PARKING LOT ISLAND a APPLICATIONS US PAT 6,277,274 Copyright c 2007 by Americast AND 6,569,321 16 FLUME (CROWNED AND SLOPED TOWARD FILTERRA THROATS) FILTERRA y� PRECAST FILTERRA I THROAT PAVED �� TOP SLAB (TYP) GUTTER TRANSITION OPENING TO PROVIDE POSITIVE (NP) AREA DRAINAGE TO THROAT OPENINGS CROWNED •.; t: CONCRETE OR PAVED FLUME _ FLOW '. •`' `. :' ';• ':;.. 4„ MIN PRECAST : r 6' MAX FILTERRA FILTERRA UNIT BOX WALL CAST-IN-PLACEOWE MID) FLUME & GUTTER (DTMPjL o f `� 7 j 4THROATS --: W POINT SECTION VIEW OF CURB <8>(TYP> CROWNED FLUME RM FILTERRA FLUME (SLOPED TOWARD FILTERRA UNIT IN�E" OPENING THROAT , FILTERRA THROAT) CROWNED FLUME CORNER FILTERRA 6" MAX TOP SLAB r CURB CAST-IN-PLACE r/,. .'. r• ?..3. ..'..'::. . FLUME & GUTTER DOWEL �;,._l GUTTER TRANSITION TO 3 PRECAST ' - PROVIDE POSITIVE DRAINAGE PAVED FILTERRA TO To THROAT OPENING BOX WALL AREA FILTERRA FLOW UNITS THROAT SECTION VIEW OF FILTERRA - � ® THROAT AND FLUME / CONCRETE OR /� PAVED FLUME STORM 3 0 J CURB i� ® DRAIN INLET MID) 1 FLOW _ / ` PAVED LOW POINT AREA THROAT FILTERRA FLOW _ CONCRETE OR UNIT PAVED FLUME THROAT TWO FLUME CORNER CONCRETE OR 3o PAVED FLUME CURB u- (TYP) 7STORM LOW POINT DRAIN INLET MODIFICATIONS OF DRAWINGS ARE ONLY PERMITTED ONE FLUME CORNER BY WRITTEN AUTHORIZATION FROM FILTERRA DATE: 01-03-05 DWG: PLG3 FILTERRA® EXAMPLE SCENARIOS ® PARKING LOT CORNER a copyr;bnc©zoo�bya�nerioasc APPLICATIONS US PAT 6,277,274 AND 6,569,321 17 SDR-35 PVC COUPLING FILTERRA STORMWATER TREATMENT INFILTRATION BYPASS CAST INTO PRECAST BOX WALL SYSTEM AS PROVIDED BY AMERICAST (OUTLET PIPE LOCATION VARIES) (REFER TO PRECAST FILTERRA UNIT TO APPROPRIATE DRAWINGS FOR DETAILS NOT SHOWN) — OUTFALL — POTENTIALLY INTERNAL PERFORATED PIPING THROUGH OTHER INCLUDED WITH FILTERRA UNIT FINISHED GRADE INFILTRATION CELL(S) OPTIONAL �• ._ _. OBSERVATION C-4 Q cD o AND/OR r.., I CLEANOUT I � .� •q w 0 TOP OF INFILTRATION CELLS) j L = TO BE AT A LOWER ELEVATION J THAN BOTTOM OF FILTERRA UNIT PERFORATED PIPING WITHIN THE LIMITS OF THE INFILTRATION CELL SECTION VIEW INFILTRATION CELL REMOTE INFILTRATION CELL SDR-35 PVC COUPLING CAST INTO PRECAST FILTERRA STORMWATER TREATMENT BOX WALL (OUTLET PIPE LOCATION VARIES) SYSTEM AS PROVIDED BY AMERICAST (REFER TO PRECAST FILTERRA UNIT FINISHED GRADE INTERNAL PERFORATED PIPING DRAWINGS FOR DETAILS NOT SHOWN) INCLUDED WITH FILTERRA UNIT 0 OPTIONAL OBSERVATION I 0 AND/OR OPTIONAL Lli > d > CLEANOUT _ - z _ _OBSERVATION AND/OR CLEANOUT 1�11a°•a-:i y'• •���,�~'� ;:a-•.c '-^,:•••-:�:�•: .� . • , I. � I I_)I d INFILTRATION CELL TO BE DESIGNED FOR 2000 LBS/SQ FT f UNIFORM BEARING CAPACITY 6" MIN BEDDING MATERIAL INFILTRATION BYPASS TO PERFORATED PIPING APPROPRIATE OUTFALL — WITHIN THE LIMITS OF INTERMEDIATE BRIDGING POTENTIALLY THROUGH THE INFILTRATION CELL LAYER(S) AS NECESSARY OTHER INFILTRATION CELL(S) SECTION VIEW INFILTRATION CELL BENEATH FILTERRA MODIFICATIONS OF DRAWINGS ARE ONLY PERMITTED BY WRITTEN AUTHORIZATION FROM FILTERRA DRAWING AVAILABLE IN TIF FILE FORMAT. DATE: 07-07-06 DWG: FTINF-2 0 PRECAST FILTERRA® FOR fi h fra" INFILTRATION APPLICATIONS US PAT 6,277,274 Copyright C 2007 by Americast a? AND 6,569,321 � � ® � � � II�IIIII�lllllF�lllu GRASS SWALE FILTERRA dll®IIIII®IIIII®IIIII®IIIII®IIIII®IIIII®IIIII®IIIII®IIIII®IIIII ®IIIII®IIIII®IIIII®IIIII IIIII IIIII IIII) I � IIIII IIII IIII IIII �,IIIIIIIII IIII IIII IIII IIII IIII IIIII ®IIIII® �IIIII IIII�1�111' Hill II II II MHU I I I IIII I I��I II I IIII -►--.;,;�, I Mill II1II1I1I Hill I1III1IIII IIIIlul l II � wiiII �I I I I I I I II I P IIIIm HHH 1HHIN IIIIP' ®IIIII®IIIII®IIIII®IIIII®IIII�'""��, � '"''�"�'� IIIII IIIII I III�"" i�HHiI IWHINI H191 IIf IIIII IIIII III IUi� IIIII IIII IIII � ��� CONCRETE SWALE AND f IIII IIII III, III, TRANSITION AT FILTERRA I III I��III�' IIII III IIII Illl�lu,� III IIII ISOMETRIC VIEW r � - FILTERRA BYPASS FLOW DIRECTED TO A LOWER POINT OF RELIEF I I CONCRETE CURB (TYP) BY OTHERS I I OUTLET PIPE (BY OTHERS) I I TO APPROPRIATE OUTFALL 2'-0" I I 2'-0" MIN I I MIN I I }--------------- \ j FLOW f 1 f N N FLOW FLOWLINE OF SWALE w w w w SLOPED DOWN TO A ao ELEV 'A' CL a. p AN APPROPRIATE BYPASS -9 9 3 3 AT A LOWER ELEVATION cn THAN ELEV 'A' CONCRETE SWALE AND TRANSITION AT FILTERRA (BY OTHERS) PLAN VIEW CAST IN PLACE GUTTER TRANSITION (BY OTHERS) ,i SWALE WIDTH AS REQUIRED PRECAST 6"f FILTERRA , TOP SLAB : CAST IN PLACE CONCRETE SWALE (BY OTHERS) ° FLOWLINE OF SWALE MIN 4"/MAX 6" ��THROAT OPENING ON EITHER SIDE OF CAST IN PLACE CONCRETE FILTERRA PRECAST GUTTER AT THROAT OPENING FILTERRA (BY OTHERS) BOX WALL SECTION VIEW AT FILTERRA DRAWING AVAILABLE IN TIF FILE FORMAT. DATE: 03-10-05 I DWG: FTSWL-1 PRECAST UNIT TYPICAL SWALE Copyright AND 6,569ght©2005byAmericast CONFIGURATION US PAT 569,32,274 1 19 4" SDR-35 GASKETED COUPLING CAST INTO PRECAST WALL (LOCATION VARIES) PARKING LOT OR STREET m 4" PVC OUTLET PIPE (BY OTHERS) FACE OF CURB CONNECT TO APPROPRIATE co GRASS OUTFALL (LOCATION VARIES) 48" THROAT /' ` 1 d / I I I M .. . .r M .................... ... .................. ... .. ° k - ..d•" ••d•.•••�� ao e .: �'° � ••d. a•. ao I o o I o I I MODIFIED FILTERRA TOP SLAB SIDEWALK CENTER OF 3X3 TREE GRATE 60" BOX SIZE DIM. "A" TREE GRATEI 4X8 & 6X8 9'-0" 3'x3' I MODIFIED NARROW LENGTH I 6X10 11'—O" 3'x3' I FILTERRA UNIT ONLY FOR 4X8 (SHOWN) PLEASE NOTE 6X8 AND 6X10 BOXES MODIFICATION ON PROJECT - INFORMATION 6C0 COUPLING I G CAST INTO FORM PRECAST WALL PARKING LOT OR STREET 6" PVC OUTLET (LOCATION VARIES) PIPE (BY OTHERS)NECT TO CENTER OF 4X4 FACE OF CURB of APPROPRIATE N OUTFALLL TREE GRATE __ D GRASS (LOCATION VARIES) 1 I I .• .. d s••••••• 'II OOopOo°p0Qo�a o��oO�°O°1D40�4" THROAT ...... 6V174 m o�Oo .n • JII I I °Q00 LT---------------J d ... P. .. .co . a d' .d, ' ,d SIDEWALK BOX SIZE DIM "A" DIM "B" TREE GRATEI STANDARD NARROW WIDTH 16X4 & 8X4 5'-0" 8'-0" 3'x3' I FILTERRA UNIT I 6X6 & 8X6 7'-0" 9'-0" 3'x3' I 11OX6 & 12X6 7'-0" 9'-6" 4'x4'* I SUITABLE FOR ALL I 13X7 8'-0" 10'-0" 4'x4'* I STANDARD BOXES MODIFICATIONS OF DRAWINGS ARE ONLY *3'x3' TREE GRATE IS OPTIONAL PERMITTED BY WRITTEN AUTHORIZATION FROM FILTERRA DATE: 09-04-07 DWG: FTSC-2 TYPICAL FILTERRA® SIDEWALK CONFIGURATIONS US PAT 66,,277,274 Copyright C 2007 by Americast TOLL FREE(866)349-3458 94 AND 6,569,321 B F— FILTERRA UNIT 4"0 PIPE FROM FILTERRA TO CURB (TYP) STORM DRAIN PIPE FROM _----_---�� STORM DRAIN ROOF RUNOFF II GRATE I� OUTFALL PIPE FROM STOM FLOW pP� /-ae — DRAINGRATE FLUME PLAN ALr=-= 5/ / JA THROAT J L� CONCRETE OR LOW POINT B PAVED FLUME STANDARD ELEV'A'MUST GRADE CURB BE HIGHER ELEV'B' MUST THAN ELEV'B' BE HIGHER (TYP) SLOPE THAN ELEV'C' FILTERRA THROAT FLUME FLOW FLUME FLOW PIPE FROM - PIPE OUTLET ROOF RUNOFF ELEVATION'A' _ GRATE DRAIN FILTERRA FLOWLINE ELEV'C' DEPRESSED AREA AT FLOWLINE ELEV'B' THROAT OPENING (TYP) FLUME CROSS SECTION A—A FILTERRA FLUME (SLOPED TOWARD THROAT OPENING FILTERRA THROAT) PRECAST 4" MIN FILTERRA 6" MAX TOP SLAB CURB FLUME SECTION B—B CAST—IN—PLACE _ . FLUME & GUTTER DOWEL f GUTTER TRANSITION TO PRECAST — PROVIDE POSITIVE DRAINAGE FILTERRA = `' TO THROAT OPENING BOX WALL MODIFICATIONS OF DRAWINGS ARE ONLY PERMITTED BY WRITTEN AUTHORIZATION FROM FILTERRA DATE: 03-17-05 DWG: FTRDF-1 Q , ������ FILTERRA® EXAMPLE SCENARIOS fi h 1 ® ROOF DRAIN FLUME o Copyright©2007byAmericast APPLICATION US PAT 6,277,274 �� AND 6,569,321 6) filteffa Bioretention Systems Section C Standard Filterra° Detail Drawings & FilterraO Plan Notes For TIF versions of these detail drawings,please contact Americast. Toll Free: (866) 349-3458 E-mail: support@fIterra.com Reproduction of these detail drawings is permitted for use only in site plans or contract documents for eventual supply by Americast or its authorized dealer. Other uses are prohibited and may infringe copyright or patent protection laws. Filterra and Americast reserve the right to alter specif cations without notice. Please make certain the Filterra Project Information Form is completed to ensure the verif cation of the latest specif cations for your project. Toll Free: (866)349-3458 Fax: (804)798-8400 support@fIterra.com 22 www.filterra.com CURB INLET —\ p�0pa0�Opp��p FILTERRA �` �o�opOpa�ODpo�Q DO Oa oOQ00OQ�OO�D�Q LLLLL epoOO�Q�OQp4 LLLLLL LLL PLAN VIEW STANDARD TRANSITION FROM ELEV 'A' MUST CURB AND STANDARD TO BE HIGHER GUTTER DEPRESSED (TYP) GUTTER (TYP) THAN ELEV 'B' SLOPE FILTERRA THROAT � CURB INLET THROATI �\\\\mmx\\ GUTTER FLOW GUTTER FLOW DEPRESSED GUTTER AT FILTERRA BYPASS CURB INLET THROAT OPENING (TYP) FLOWLINE ELEV'A' FLOWLINE ELEV'B' ELEVATION VIEW INTERLOCKING FILTERRA UNIT - STORMWATER JOINT (TYP) o0 STRUCTURE 0- ::: j OUTLET PIPE N I '°•: (BY OTHERS) CONNECT M > TO STORM DRAIN � Z EFFLUENT 1 • • PERFORATED '• INVERT OUT / cD STER / UNDERDRAIN SYSTEM (3'-6"> STRUCTURE BY AMERICAST EFFLUENT IN (MUST BE LOWER) CROSS SECTION MODIFICATIONS OF DRAWINGS ARE ONLY PERMITTED BY WRITTEN AUTHORIZATION FROM FILTERRA DATE: 07-07-06 DWG: FLP-2 FILTERRA® TYPICAL FLOWLINE fl h ���® IrCopyright!C 2007 by Americast AND OULET PIPE RELATIONSHIP US PAT 6,277,274 �? AND 6,569,321 0o T ' o0 pO Oa . O O a O O A O 0 0 00 Oo oD a - 00 oa 0 .0 ®�a� �D��� FILTERRA TOP d d d SLAB d a a CURB (BY OTHERS) B �^ B CURB (BY OTHERS) s s BYPASS FLOW FLOW �A F�o� Foil PLAN VIEW \\\\\\\\\\\\\\ FILTERRA THROAT STANDARD FLOW BYPASS FLOW CURB PAVEMENT TRANSITION TO FILTERRA THROAT NOTE: CONTRACTOR RESPONSIBLE FOR PROVIDING SECTION VIEW EROSION & SEDIMENT INLET PROTECTION. THE MEDIA SURFACE MUST NOT RECEIVE B—B ANY CONSTRUCTION SEDIMENT OR DEBRIS. VERTICAL CURBING SLOPED CURBING STANDARD 90' NOSING MODIFIED 45' NOSING (OTHER NOSING AVAILABLE FOR SLOPED GRANITE UPON REQUEST) CURBING PRECAST I PRECAST TOP SLAB I t` TOP SLAB � a PAVEMENT PAVEMENT v THROAT PROTECTION THROAT PROTECTION •.!.~i•... DEVICE — DO NOT DEVICE — DO NOT REMOVE REMOVE PRECAST... ,r: PRECAST BOX WALL BOX WALL SECTION VIEW A—A DATE: 05-10-11 DWG: NE CGT-6 MODIFIED FILTERRA@ 1�cU�%U�Lti T ROAT O EN NG DETAIL fi Remo Copyright0c 2007 by Americast FOR GRANITE CURBING - NE US PAT 6,277,274 AND 6,569,321 L'+ 6) filteffa Filterra® Standard Plan Notes Bioretention Systems Construction & Installation A. Each unit shall be constructed at the locations and elevations according to the sizes shown on the approved drawings.Any modif cations to the elevation or location shall be at the direction of and approved by the Engineer. B. If the Filterra®is stored before installation, the top slab must be placed on the box using the 2x4 wood provided, to prevent any contamination from the site.All internal f ttings supplied(if any), must be left in place as per the delivery. C. The unit shall be placed on a compacted sub-grade with a minimum 6-inch gravel base matching the f nal grade of the curb line in the area of the unit. The unit is to be placed such that the unit and top slab match the grade of the curb in the area of the unit. Compact undisturbed sub-grade materials to 95% of maximum density at+1- 2% of optimum moisture. Unsuitable material below sub-grade shall be replaced to the site engineer's approval. D. Outlet connections shall be aligned and sealed to meet the approved drawings with modif cations necessary to meet site conditions and local regulations. E. Once the unit is set, the internal wooden forms and protective mesh cover must be left intact. Remove only the temporary wooden shipping blocks between the box and top slab. The top lid should be sealed onto the box section before backf lling,using a non-shrink grout,butyl rubber or similar waterproof seal. The boards on top of the lid and boards sealed in the unit's throat must NOT be removed. The Supplier(Americast or its authorized dealer) will remove these sections at the time of activation. Backf lling should be performed in a careful manner, bringing the ap- propriate f 11 material up in 6" lifts on all sides. Precast sections shall be set in a manner that will result in a watertight joint. In all instances, installation of Filterra®unit shall conform to ASTM specif cation C891 "Standard Practice for Installation of Underground Precast Utility Structures", unless directed otherwise in contract documents. F. Curb and gutter construction(where present) shall ensure that the f ow-line of the Filterra®units is at a greater elevation than the f ow-line of the bypass structure or relief(drop inlet, curb cut or similar). Failure to comply with this guideline may cause failure and/or damage to the Filterra® environmental device. G. Each Filterra®unit must receive adequate irrigation to ensure survival of the living system during periods of drier weather. This may be achieved through a piped system, gutter f ow or through the tree grate. 25 www.filterra.com 6) filteffa Bioretention Systems Activation A. Activation of the Filterra®unit is performed ONLY by the Supplier. Purchaser is responsible for Filterra® inlet protection and subsequent clean out cost. This process cannot commence until the project site is fully stabilized and cleaned (full landscaping, grass cover, f nal paving and street sweeping completed), negating the chance of construction materials contaminating the Filterre system. Care shall be taken during construction not to damage the protective throat and top plates. B. Activation includes installation of plant(s) and mulch layers as necessary. Included Maintenance A. Each correctly installed Filterre unit is to be maintained by the Supplier, or a Supplier approved contractor for a minimum period of I year. The cost of this service is to be included in the price of each Filterra®unit. Extended maintenance contracts are available at extra cost upon request. B. Annual included maintenance consists of a maximum of(2) scheduled visits. The visits are scheduled seasonally; the spring visit aims to clean up after winter loads that may include salts and sands. The fall visit helps the system by removing excessive leaf litter. C. Each Included Maintenance visit consists of the following tasks. I. Filterra®unit inspection 2. Foreign debris, silt, mulch&trash removal 3. Filter media evaluation and recharge as necessary 4. Plant health evaluation and pruning or replacement as necessary 5. Replacement of mulch 6. Disposal of all maintenance refuse items 7. Maintenance records updated and stored(reports available upon request) D. The beginning and ending date of Supplier's obligation to maintain the installed system shall be determined by the Supplier at the time the system is activated. Owners must promptly notify the Supplier of any damage to the plant(s), which constitute(s) an integral part of the bioretention technology. 26 www.filterra.com 6 W 6" to F----------------------------I ' A i i A SDR-35 PVC COUPLING CAST INTO PRECAST BOX WALL BY AMERICAST (OUTLET PIPE LOCATION VARIES) L---------------------------J- ' I �� CURB (BY OTHERS) PLAN VIEW I TREE FRAME PLANT AS SUPPLIED CLEANOUT COVER & GRATE BY AMERICAST CAST IN TOP SLAB CAST IN (NOT SHOWN TOP SLAB FOR CLARITY) GALVANIZED TOP SLAB ` ANGLE NOSING 00 f71 STREET MODIFIED WALL CD w MULCH PROVIDED z . . BY AMERICAST TARP/TAPE APPROVED V FILTERRA MEDIA PROVIDED BY AMERICAST t UNDERDRAIN STONE io PERFORATED UNDERDRAIN PROVIDED BY AMERICAST SECTION A—A SYSTEM BY AMERICAST DESIGNATION L. W TREE GRATE OUTLET QTY & SIZE PIPE 4 x 6 4'-0" 6'-0" (1) 3x3 4" SDR-35 PVC 4 x 8 4'-0" 8'-0" (1) 3x3 4" SDR-35 PVC 4 x 12 4'-0" 12'-0" (2) 3x3 4" SDR-35 PVC 6 x 8 6'-0" 8'-0" (1) 4x4 4" SDR-35 PVC 6 x 10 6'-0" 10'-0" (1) 44 6" SDR-35 PVC 6 x 12 6'-0" 12'-0" (2) 4x4 6" SDR-35 PVC 7 x 13 7'-0" 13'-0" (2) 44 6" SDR-35 PVC MODIFICATIONS OF DRAWINGS ARE ONLY PERMITTED BY WRITTEN AUTHORIZATION FROM FILTERRA DATE: 05-05-11 DWG: NE FTNL-3 PRECAST FILTERRA@ UNIT , ������ NARROW LENGTH CONF GURATION Copyright 2007byAmericast NORTHEAST REGION US PAT 6,277,274 AND 6,569,321 27 6" W 6" --------------------7-' I I I I I I A i \' `\ i A I I I I SDR-35 PVC COUPLING I I CAST INTO PRECAST BOX WALL BY AMERICAST (OUTLET I I PIPE LOCATION VARIES) I I I I I I L---------------------<— I I �� CURB (BY OTHERS) PLAN VIEW TREE FRAME & GRATE CAST IN TOP SLAB PLANT AS SUPPLIED CLEANOUT COVER BY AMERICAST CAST IN TOP SLAB (NOT SHOWN TOP SLAB FOR CLARITY) GALVANIZED ANGLE NOSING INTERLOCKING JOINT (TYP) 00 �; I° :• +e' ...• — � STREET o MODIFIED WALL 0 N n~ MULCH PROVIDED z BY AMERICAST 4 s` TARP/TAPE APPROVED • •Q i FILTERRA MEDIA PROVIDED BY AMERICAST UNDERDRAIN STONE io PERFORATED PROVIDED BY AMERICAST UNDERDRAIN SYSTEM BY AMERICAST SECTION A-A DESIGNATION L W TREE GRATE OUTLET QTY & SIZE PIPE 4 x 4 4'-0" 4'-0" (1) 3x3 4" SDR-35 PVC 6 x 6 6'-0" 6'-0" (1) 3x3 4" SDR-35 PVC MODIFICATIONS OF DRAWINGS ARE ONLY PERMITTED BY WRITTEN AUTHORIZATION FROM FILTERRA DATE: 05-05-11 1 DWG: NE FTST-2 PRECAST 1 U UNIT �%LI�L� STA DARDFCONFIGURATION ��Refra® Copyright Oczoo,byAmer;casr NORTHEAST REGION "ANpTs 6,277,274 28 6„ � I W � 6„ r-------------7 I � I I I I I A A 4SDR-35 PVC COUPLING I I CAST INTO PRECAST BOX I I I WALL (OUTLET PIPE I ; I LOCATION VARIES) I L------I-- ----1- ' I I '\/- CURB (BY OTHERS) PLAN VIEW _ CLEANOUT PLANT AS SUPPLIED BY AMERICAST COVER TREE FRAME & GRATE CAST IN ^ (NOT SHOWN CAST IN TOP SLAB TOP SLAB FOR CLARITY) TOP SLAB GALVANIZED f ANGLE NOSING ° STREET a — 0 MODIFIED WALL `'4 I , MULCH PROVIDED r7 z BY AMERICAST TARP/TAPE APPROVED FILTERRA MEDIA PROVIDED P BY AMERICAST UNDERDRAIN STONE PERFORATED UNDERDRAIN PROVIDED BY AMERICAST SYSTEM BY AMERICAST SECTION A-A DESIGNATION L W TREE GRATE OUTLET QTY & SIZE PIPE 6 x 4 6'-0" 4'-0" (1) 3x3 4" SDR-35 PVC 8 x 4 8'-0" 4'-0" (1) 3x3 4" SDR-35 PVC 8 x 6 8'-0" 6'-0" (1) 4x4 4" SDR-35 PVC 10 x 6 10'-0" 6'-0" (1) 4x4 6" SDR-35 PVC 12 x 4 12'-0" 4'-0" (2) 3x3 4" SDR-35 PVC 12 x 6 12'-0" 6'-0" (2) 4x4 6" SDR-35 PVC 13 x 7 13'-0" 7'-0" (2) 4x4 6" SDR-35 PVC MODIFICATIONS OF DRAWINGS ARE ONLY PERMITTED BY WRITTEN AUTHORIZATION FROM FILTERRA DATE: 05-05-11 DWG: NE FTNW-3 PRECAST FILTERRA@ UNIT NARROW WIDTH CONFIGURATION fififra Copyright©2007bypmer;cast NORTHEAST REGION US PAT 6,277,274 AND 6,569,321 29 CONNECTION TO SOAKER/SWEAT HOSE OR SPRINKLER HEAD (BY OTHERS) TOP OF CURB TOP SLAB IRRIGATION/SPRINKLER PIPE (BY OTHERS) —\ APPROX i--i 12.5" 2" PVC CONDUIT PRECAST INTO CENTER OF EACH BOX WALL / UNIT MULCH LAYER , SIZE A B BY AMERICAST 4 x 6 2'-6" 3'-6" 14 x 8 2'-6" 4'-6" 14 x 12 2'-6" 6'-6" 16 x 6 3'-6" 3'-6" ELEVATION VIEW 6 x 8 3'-6" 4'-6" 6 x 10 3'-6" 5'-6" 6 x 12 3'-6" 6'-6"I I A 6» 7 x 13 4'-0" 7'-0" 8 x 4 4'-6" 2'-6"I ------------11------------, 36" OR 48„ 18 x 6 4'-6" 3'-6" TREE GRATE i 10 x 6 5'-6" 3'-6" 112 x 4 6'-6" 2'-6" I i / i 2" PVC 12 x 6 6'-6" 3'-6"I I CONDUIT I13 x 7 7'-0" 4'-0"I ZB : CENTERTOFTO EACH BOX IRRIGATION/SPRINKLER WALL PIPE (BY OTHERS) CONNECTION TO _ SOAKER/SWEAT HOSE OR SPRINKLER HEAD -------- —t-------------------------- ---�- (BY OTHERS) -------- FACE OF FILTERRA THROAT J CURB OPENING co PLAN VIEW MODIFICATIONS OF DRAWINGS ARE ONLY PERMITTED DRAWING AVAILABLE IN TIF FILE FORMAT. BY WRITTEN AUTHORIZATION FROM FILTERRA DATE: 09-14-07 DWG: FTIRR-2 0 FILTERRA® IRRIGATION fifirra" copyr gnc©Zoos by Amer,�ast PLANNING LAYOUT US PAT 6,277,274 79 AND 6,569,321 0 filterra Bioretention Systems Section D Filterra° Technical Section Toll Free: (866)349-3458 Fax: (804)798-8400 support@fIterra.com 31 www.filterra.com Americast Filterra Weights and Lifting Details Box Only UD Stone+ Media Top Only Box+Top Box+Media Box+ Media+Top *Spreader Bar Pounds Tons Pounds Tons CY Pounds Tons Pounds Tons Pounds Tons Pounds Tons Min Max 4x6 7,440 3.72 5,167 2.58 2.00 2,819 1.41 10,259 5.13 12,607 6.30 15,426 7.71 5.00 ft 7.50 ft 0 0 4x8 9,145 4.57 6,890 3.44 2.67 3,829 1.91 12,974 6.49 16,035 8.02 19,864 9.93 5.00 ft 7.50 ft 4x12 12,555 6.28 10,334 5.17 4.00 5,231 2.62 17,786 8.89 22,889 11.44 28,120 14.06 5.00 ft 7.50 ft 6x4 7,285 3.64 5,167 2.58 2.00 3,417 1.71 10,702 5.35 12,452 6.23 15,869 7.93 5.50 ft 7.50 ft Std 6x6 9,300 4.65 7,751 3.88 3.00 4,221 2.11 13,521 6.76 17,051 8.53 21,272 10.64 7.00 ft 9.00 ft 0 0 6x8 11,315 5.66 10,334 5.17 4.00 5,121 2.56 16,436 8.22 21,649 10.82 26,771 13.39 7.00 ft 9.00 ft `D 6x10 13,330 6.67 12,918 6.46 5.00 6,545 3.27 19,875 9.94 26,248 13.12 32,793 16.40 7.00 ft 9.00 ft 6x12 15,345 7.67 15,502 7.75 6.00 6,825 3.41 22,170 11.09 30,847 15.42 37,672 18.84 7.00 ft 9.00 ft w 0 0 7x13 17,593 8.80 19,592 9.80 7.58 10,106 5.05 27,699 13.85 37,185 18.59 47,291 23.65 8.00 ft 10.00 ft 0 0 8x4 8,835 4.42 6,890 3.44 2.67 3,787 1.89 12,622 6.31 15,725 7.86 19,511 9.76 5.50 ft 7.50 ft 00 8x6 11,160 5.58 10,334 5.17 4.00 5,100 2.55 16,260 8.13 21,494 10.75 26,594 13.30 7.50 ft 9.50 ft w 0 14 0 10x6 13,020 6.51 12,918 6.46 5.00 6,503 3.25 19,523 9.76 25,938 12.97 32,441 16.22 7.50 ft 9.50 ft o t w q 0 12x4 11,935 5.97 10,334 5.17 4.00 5,146 2.57 17,081 8.54 22,269 11.13 27,415 13.71 5.50 ft 7.50 ft 12x6 14,880 7.44 15,502 7.75 6.00 6,762 3.38 21,642 10.82 30,382 15.19 37,143 18.57 7.50 ft 9.50 ft o f6 0 13x7 17,593 8.80 19,592 9.80 7.58 10,042 5.02 27,635 13.82 37,185 18.59 47,227 23.61 8.50 ft 10.50 ft in t * BOX AND TOP MUST BE LIFTED SEPARATELY 32 *A 7.50 ft spreader bar is suitable for all sizes shown. RL i IF.............]IZZ1,1111111111-WA 12 X 4 B 6X6B 4X8B 6X8B 8X4B 8X6B 4X6B 6X4B I> t + ,,,,,,I 4X 2B � 6X10B 6X12B 7X13B 10X6B 12X6B 13X7B MODIFICATIONS OF DRAWINGS ARE ONLY PERMITTED BY WRITTEN AUTHORIZATION FROM FILTERRA DRAWING AVAILABLE IN TIF FILE FORMAT. DATE: 09-14-07 DWG: FTOPC-2 0 FILTERRA® PVC OUTLET fi h fra" PIPE COUPLING LOCATIONS u US PAT 6,277,274 Copyright C 2007 by Americast 77 AND 6,569,321 6) filleffa Filterra® Piping Technical Details Bioretention Systems Filterra® is supplied with an internal underdrain system that exits a wall in a perpendicular direction. Most eff cient drainage is accomplished when the drain exits on the lower side of the Filterra®, i.e. nearest the overf ow bypass. This is more important when using the larger sized Filterras®. Drawing DPI: P171EC45T FlLTERRk BOX WALL — �— SOa_35 PSG COVPUNG C45T Section View through Filterra " •' r INTO PR US BOk WALL (9V AMERICAST) Precast Box Wall at Outfall Pipe SDR-35 I"YC OUFFALL PIPE AT + a. 1 INTERNAL FILTERRa Connection FAIN 6.507E SLDPE TO ONTFALL 1 INTERNAL Fi ERRA i (9Y ETHERS) - ,� 'f' (BY AMERICbST) O O O O All units are supplied with the I drainage pipe coupling precast into the wall, at a depth of 3.50 feet (INV to TC). Drawing DPI � . is a detail of the coupling. The P"EVIAW FILTEIiFA UUM BASE • '�' coupling used is SDR-35 PVC. Typically, an outfall slope of 1.0% is preferred to accommodate the flow of treated water from the Filterra®, but each site may present unique conditions based on routing of the outfall pipe (elbows). The pipe must not be a restricting point for the successful operation of Filterra®.All connecting pipes must accommodate freefall f ow. Table 3 lists expected flow rates of the various size Filterra®units and these flow rates can be used to conf rm or calculate the minimum outfall pipe slope. Table 3: Filterra Flow Rates & PiDe Details Filterra® Size Expected Flow Rate (cubic Connecting Drainage (feet) feet/second) Pipe 4x6.or 6x4 0.056 4" SDR-35 PVC 4x8 or 8x4 0.075 4" SDR-35 PVC 6x6 0.084 4" SDR-35 PVC 6x8 or 8x6 0.112 4" SDR-35 PVC 4x12 or 12x4 0.112 4" SDR-35 PVC 6x10 or 10x6 0.140 6" SDR-35 PVC 6x12 or 12x6 0.168 6" SDR-35 PVC 7x13 or 13x7 0.213 6" SDR-35 PVC 34 www.filterra.com 0 filterra Bioretention Systems Filterra°Modified Options: Recessed Tops Filterra®modif ed recessed tops allow a seamless integration using pavers, mulch or sod. NOTE: Modif ed recessed tops increase the depth of the Filterra® invert out. Modif ed recessed top with sod • •R Modif ed recessed top prior to shipping CLEANOUT TREE GRATE & FRAME & COVER STEEL FRAME . 4" AN P 10 — 12" a b tr a riro' 6 � a p 35 www.filterraxom 6) Common Filterra° • Qrfa Placements G I m �r Providing parking lot treatment by Typical Filterra placement at a fast Even the largest Filterra unit blends in impaired waters. food chain. with landscaping. r ti `i Filterra used with a flumed bypass in a Ideal for stormwater treatment where Filterra featuring a beautiful Crape commercial parking lot. space is tight. Myrtle in bloom. 36 6) filteffa Filterra° Plant Selections Bioretention Systems The Filterra® Stormwater Bioretention Filtration System harnesses the power of nature to capture, immobilize and cycle pollutants to treat stormwater runoff. Trees, grasses and shrubs do more than make it attractive; they also enhance pollutant removal. Above ground, the system' s shrubs, grasses or trees add beauty and value to the urban landscape. Underground, nature's complex physical, chemical and biological processes are hard at work removing a wide range of non-point source pollutants from treated stormwater Pollutants are decomposed, volatilized and incorporated into the biomass of Filterra's micro/macro fauna and f ora. A wide range of plants are suitable for use in bioretention systems, and a list is available indicating those suitable for use with Filterra. The selection varies by location according to climate. Additional photos are available at www .f lterra.com. Some of the most popular selections to date are shown below: 1 Filterra®with Crape Myrtle Filterra®with Foster Holly ti 1 f A Y _ 4 Filterra®with Northern Bayberry Filterra®with Serviceberry 37 www.filterra.com Bioretention f I e f Plant/Soil/Microbe Complexfa Pollutants,Removes Phosphorus, Bacteria, Heavy Metals, Hydrocarbons, Newor ExistingFilterraO Flow at Higher Elevation Curb Cut or than Bypass Flow Line Other Means of Overflow Relief Clean-out ' - High Flow Bypass Gutter ' Storm Water Inflow ' ' + 3"Mulch ("First Flush") - f _ Filterra° Engineered Energy Dissipator Media Stones Filterra° Concrete Treated Stormwater Container Underdrain System A Division of�IICMERIICAST U.S.Patents#6,277,274&#6,569,321.Other Patents pending.