HomeMy Public PortalAboutAppendix E_Hydrology Report and WQMP
HYDROLOGY REPORT
For
Pointe Common
1600 West Commonwealth Avenue,
Fullerton, CA 92833
December 2022
Prepared for:
Meta Housing Corp.
11150 W. Olympic Blvd., Suite 620
Los Angeles, CA 90064
Prepared by:
6420 Wilshire Blvd., Suite 1000
Los Angeles, CA 90048
Tel: (909) 559-7361
Contact: Matt Plourde
TABLE OF CONTENTS
A. INTRODUCTION
1. Purpose
2. Project Description
3. Basis of Design
B. PROJECT SITE CONDITIONS
1. Pre-Development Condition
2. Post-Development Condition
C. HYDROLOGIC ANALYSIS
1. Methodology
2. Results and Conclusions
D. HYDRAULIC ANALYSIS
1. Scope
2. Methodology
3. Results and Conclusions
APPENDIX
A: Hydrology Maps
B: Hydrologic Calculations
C: Supporting Documents
D: FEMA Flood Map
E: Hydraulic Calculations
A. INTRODUCTION
Purpose
The scope of this report is to present the existing and proposed drainage
characteristics of the subject property. The proposed drainage facilities are evaluated
for the 2-year and 100-year, 24-hour storm.
The purpose of this report is to show what the effect of the proposed project will
be on the overall hydrologic condition of the subject property.
Project Description
The project is located at 1600 W Commonwealth Ave, Fullerton, CA 92833. See
vicinity map below. The property is currently undeveloped and is being used as a public
works laydown yard. There are no permanent structures onsite however there are
several temporary storage containers scattered throughout the property.
The proposed project will involve the construction of a 65-unit affordable
housing development. The project will construct a 3-story building for the housing units
as well as build an on-grade parking lot for the residents. There will also be several
landscape and hardscape improvements around the site including walkways, seating
areas, and lawn and garden space.
Vicinity Map
Basis of Design
This report and calculations shown within will be based on the Orange County
Hydrology Manual as well as the OC Local Drainage Manual.
B. Project Site Conditions
Existing On-Site Condition
Based on the topographic survey for the property the existing site is relatively
flat. There is only about 3-4 feet of grade change over the entire site. The majority of
the site slopes from south to north and from east to west. There is a smaller section of
the site which appears to flow from north to south.
There are no distinguishable drainage measures onsite and the site appears to
drain via sheet flow. Most of the site sheet flows over the sidewalk on Commonwealth
Ave and into the gutter located on the south side of the street. A smaller portion of the
site appears to sheet flow onto the railroad right of way located south of the property.
Per the FEMA Flood Map the site is located in a flood zone X with a 0.2% annual
chance of flood. There is no base flood elevation associated with zone x so onsite
flooding is not expected to be a concern. See Appendix D.
Existing Off-Site Condition
The site is bordered by Commonwealth Ave to the north, a fueling station to the
east, and the railroad tracks to the south.
Commonwealth Ave is fully developed with curb and gutter and no runoff from
Commonwealth appears to flow onto the property. The fueling station to the east is
sloped towards Commonwealth Ave and Basque Ave. Runoff is expected to flow
towards the public streets and not onto the subject property. The railroad tracks to the
south a very flat and no distinguishing flow path can be made. This area appears to
generally slope from east to west towards a retaining wall along Commonwealth Ave.
Runoff from the railroad tracks is not expected to enter the subject property.
Proposed On-Site Condition
After construction the site will be broken up into several sub areas. For the
purposes of this report the site was divided into 5 sub areas to be analyzed. See
Appendix A for pre and post development site maps with sub areas delineated
accordingly.
The site will no longer drain via sheet flow but will instead runoff will be
collected using gutters, catch basins, area drains, and underground pipes. Additionally,
the site will no longer sheet flow over the sidewalk on Commonwealth Ave. but will
instead drain directly to the gutter via parkway drains and curb drains. The site will also
no longer drain onto the railroad tracks to the north. This area will be redirected to
Commonwealth Ave. via underground pipes.
In addition to the storm drain improvements the project will also install 2
infiltration trench systems as part of the WQMP for the project. These infiltration
trenches will help mitigate the overall impact of the project on the site runoff.
Proposed Off-Site Condition
Offsite drainage characteristics will remain unchanged once the project is
complete.
C. Hydrologic Analysis
Methodology
Due to the relatively small size of the project area (less than 640 acres), the
rational method can be used to compute the peak runoff. The runoff analysis is based
on the proposed land use, topographic features, and proposed grading for the site area.
The average land slopes and runoff coefficients were used for computing runoff.
The runoff equation for the Rational Method is as follows:
Q = CIA
Where: Q = Peak runoff rate (CFS)
C = Runoff coefficient
I = Average rainfall intensity (in/hr)
A = Drainage area (acres)
Results
Hydrology Summary
Design Frequency 2 Year
Total Area 2.5 Acres
Percent Impervious 1.0% Existing, 70.5% Proposed
Time of Concentration 13.5 min (Pre) 10.5 min (Post)
ISOHYET See Hydrology Summary Tables
Soil Group B per OC Hydrology Map (See Appendix C)
Runoff Pre-Development – 2.44 CFS
Post-Development – 4.03 CFS
Hydrology Summary
Design Frequency 100 Year
Total Area 2.5 Acres
Percent Impervious 1.0% Existing, 70.5% Proposed
Time of Concentration 13.5 min (Pre) 10.5 min (Post)
ISOHYET See Hydrology Summary Tables
Soil Group B per OC Hydrology Map (See Appendix C)
Runoff Pre-Development – 6.67 CFS
Post-Development – 11.03 CFS
*See Appendix B for full Calculations
Conclusions
Based on the summary tables the proposed project will increase the overall
runoff from the site. This is expected since the existing condition is undeveloped and the
proposed project will increase the overall imperviousness of the site.
When the project moves into the design phase the storm drain system and the
overflow drains will have to be designed the adequately convey flows from the site.
Per the WQMP report associated with this project there are no Hydrologic
Conditions of Concern (HCOC) downstream of the subject property so
hydromodification improvements are not anticipated to be required. The project will
install infiltration BMPs which will help with reducing the overall runoff amount,
especially from smaller storm events. If the project is conditioned to further mitigate
runoff from the site then these infiltration systems can be used to lower the total runoff
from the site.
D. Hydraulic Analysis
Scope
Since this is a preliminary study and a full storm drain system has not been
developed for the onsite portion of this project yet, this section will focus on the
impacts of the project on the hydraulics in public right of way. This section will cover the
sizing for the parkway drain outlets along Commonwealth Ave., check the design
capacity of Commonwealth Ave., and check the existing catch basin sizing.
Methodology
The Orange County Local Drainage Manual will be the basis for the hydraulic
analysis. Section 3.2.1.1 will cover the design capacity of Commonwealth Ave. and
Section 3.3.2.8.3.1 will cover the catch basin sizing.
Additionally, Bentley Flowmaster software will be used to help check the sizing
of the parkway drains and the spread in Commonwealth Ave.
Results – Parkway Drains
Based on Section C of this report the project will have a post-development flow
of 11.03 CFS. The site will be drained to the street via 2 parkway drains on
Commonwealth Ave. For the purpose of this study, we have assumed that each drain
will cover 50% of the site or 5.52 CFS per drain.
We are proposing each drain be sized with a width of 42”. Per the Bentley
Flowmaster calculation each drain will have a normal depth of 3.1”. See Appendix E.
Parkway drains have a total height of 4” therefore the parkway drains are adequately
sized.
Results – Design Capacity for Commonwealth Ave
Commonwealth Ave is a multi-lane street with a speed limit of 40 mph. Per
section 3.2.1.1 the 100-year flood must be contained within the street right of way.
Using Bentley Flowmaster, the 100-year flow from section C was used to model the
spread of the runoff in the street. This model was run using the lowest longitudinal
slope along Commonwealth Ave in order to be conservative.
Based on the Flowmaster model the 100-year storm will have a spread of 16.4 ft.
The south side of Commonwealth Ave has a width of 28.2 ft from median to curb
therefore the full 100-year storm is contained. This also leaves a full lane of traffic
unaffected by the 100-year storm. See results in Appendix E.
Results – Catch Basin
There are 2 existing City owned Catch Basins Commonwealth Ave. along the
project frontage. Both these drains are 2’ wide by 3’ long. Using Chart 9B from the OC
Local Drainage Manual we checked the drain capacity against the 100-year storm. In
order to be conservative, we assumed the total runoff from the site is collected by just
one of the catch basins.
Based on the sizing chart, and using a 50% clogging factor, the catch basin will
have a depth of 0.43 ft (5.16”) over the catch basin. Commonwealth has a typical curb
height of 8” therefore the 100-year storm is contained. See chart in Appendix E.
.
Conclusion
Based on the results above the parkway drains are sized adequately for the 100-
year storm, Commonwealth Ave has capacity to convey the 100-year storm, and the
existing catch basins are adequately sized for the 100-year storm. Therefore it is
assumed that the existing street and storm drain infrastructure can support the
proposed project.
.
APPENDIX A
Hydrology Maps
A1
A2
NOT PART OF PROJECT
NOT PART OF PROJECT
28
0
'
112'
VICINITY MAP
NOT TO SCALE
A1A2
A3
A4
A5
20
5
'
11
0
'
220'
200'
VICINITY MAP
NOT TO SCALE
APPENDIX B
Hydrologic Calculations
(Per Orange County Hydrology Manual)
Regression Equations: I(t)= atb
(I= Intensity in inches/hour, t= duration in minutes)
Return Frequency
(years) a b
2 5.702 -0.574
5 7.870 -0.562
10 10.209 -0.573
25 11.995 -0.566
50 13.521 -0.566
100 15.560 -0.573
a 10
0
6
N
W
Z
U
z
= 3
H
Fri
z
w
H
z
10 30 60 100 180 360
PRECIPITATION DURATION (MIN)
ORANGE COUNTY
HYDROLOGY MANUAL
100 YR
50 YR
25 YR
10 YR
5 YR
2 YR
1440
MEAN PRECIPITATION
INTENSITIES FOR
NONMOUNTAINOUS AREAS
P.
Figure B-3
C.6.4. Estimation of Maximum Loss Rates for Pervious Areas, Fp
Table C.2 lists the maximum loss rates (inch/hour), F, for pervious
area as a function of soil group.
TABLE C.2.
MAXIMUM EFFECTIVE PERVIOUS AREA LOSS RATES (inch/hour), F
SOIL GROUP: A B C l
Fp: 0.40 0.30 0.25 0.20
Table C.2 reflects the model calibration assuming an Fp of 0.30 in/hr. for all
the considered catchments and storm return frequencies. This mean value of
Fp of 0.30 in/hr. was assigned to Hydrologic Soil Group B due to the actual
average soil conditions in the reconstitution study areas. The Fp values for
Hydrologic Soil Groups A, C, and D, were assigned to account for the
different soil types that may he found in Orange County.
C.6.5. Estimation of Catchment Maximum Loss Rates, Fm
The maximum loss rate selected from Table C.2 applies to the pervious
area fraction of the watershed. The loss rate assumed for an impervious
surface is 0.0 inch/hour. The maximum loss rate, Fm, for a catchment is
therefore given by
Erne apFp
where ap is the pervious area fractio
the pervious area (Section C.6.4).
and F
(C.7)
is the maximum loss rate
Should a catchment contain several Fm values, the composite Fm value is
determined as a simple area average of the several Fm values.
SECTION D
RATIONAL METHOD
D.I. RATIONAL METHOD EQUATION
The rational method was originally developed to estimate runoff from
small (less then one square mile) urban and developed areas and its use shall
be limited to those conditions. Basically, the rational method equation
relates rainfall intensity, a runoff coefficient, and drainage area size to the
direct peak runoff from the drainage area. This relationship is expressed by
the equation:
Q a CIA (D.1)
where
Q = the runoff in cubic feet per second (cfs) from a
given area
C = a runoff coefficient representing the ratio of
runoff to rainfall
I _ the time -averaged rainfall intensity in inches per
hour corresponding to the time of concentration
A .= drainage area (acres)
The values of the runoff coefficient (C) and the rainfall intensity (I) are based
on a study of drainage area characteristics such as type and condition of the
runoff surfaces and the time of concentration. These factors and the
limitations of the rational method equation are discussed in the following
sections. Drainage area (A) may be determined by planimetering a suitable
topographic map of the project area.
Data required for the computation of peak discharge by the rational method
are: (i) rainfall intensity (I) for a storm of specified duration and selected
design frequency; (ii) drainage area characteristics of size (A), shape, slope;
and (iii) a runoff coefficient (C).
D.2. [.IMITATIONS OF THE RATIONAL METHOD
The validity of the relationship expressed by the rational method
equation holds true only if certain assumptions are reasonably correct and
limitations of the method are observed. Two basic assumptions are that (0
the frequency of a storm runoff is the same as the frequency of the rainfall
producing this runoff; i.e., a 25 -year recurrence interval rainfall will provide
a 25 -year recurrence interval storm runoff, and (ii) that the peak runoff
occurs when all parts of the drainage area are contributing to the runoff.
The use of the rational method equation is limited to watersheds of size less
than 640 acres.
The rational method equation is only applicable where the rainfall intensity
(I) can be assumed to be uniformly distributed over the drainage area at a
uniform rate throughout the duration of the storm. This assumption applies
fairly well to small areas of less than 640 acres. Beyond this limit, the
rainfall distribution may vary considerably from the point values given in
rainfall isohyetal maps and the rational method equation should not be used.
The selection of the runoff coefficient (C) is another major limitation for the
rational method equation. For small urban and developed areas the runoff
coefficient can be reasonably well estimated from field and aerial photo
studies. For larger areas where the determination of the runoff coefficient is
to be based on vegetation type, cover density, the infiltration capacity of the
ground surface, and the slope of the drainage area, an estimate of the runoff
coefficient may be subject to a much greater error due to the variability of
the drainage area characteristics. Rainfall losses due to evaporation,
transpiration, depression and channel storage are inadequately evaluated, and
may appreciably affect the estimate of the watershed peak rate of runoff.
The effects of depth -area -duration (or depth -area) factors are not accounted
for in the simple intensity -duration curve used for rational method studies.
For large drainage areas, the absence of depth -area adjustments can result in
significant differences in the estimate of the average depth of catchment
point rainfalls.
The above limitations indicate that an estimate of the peak rate of runoff
becomes less reliable as the drainage area becomes larger and the rational
method equation should, therefore, not he used for drainage areas larger than
640 acres.
D.3. CRITICAL DURATION (TIME OF CONCENTRATION)
The critical duration of the storm rainfall required in the rational
method equation is based on the time of concentration of the drainage area.
The time of concentration (Tc) is defined as the interval of time (in minutes)
required for the flow at a given point to become a maximum under a uniform
rainfall intensity. Generally, this occurs when all parts of the drainage area
are contributing to the flow. Generally, the time of concentration is the
interval of time from the beginning of rainfall for water from the hydraul-
ically most remote portion of the drainage area to reach the point of
concentration; e.g., the inlet of the drainage structure. The time of
concentration is a function of many variables including the length of the flow
path from the most remote point of an area to the concentration point, the
slope and other characteristics of natural and improved channels in the area,
the infiltration characteristics of the soil, and the extent and type of
development. For rational method studies based on this manual, the time of
concentration for an initial subarea may be estimated from the nomograph of
Figure D-1. The time of concentration for the next downstream subarea is
computed by adding to the initial T,, the time required for the computed
peak flow to travel to the next concentration point. Time of concentration is
computed for each subsequent subarea by computing travel time between
subareas and adding to the cumulative sum.
L
m
c
0
a,
0
v
4-
0
J
.c
at
m
J
1000
900
800
700
600
500
400
350
300
250
200
150
100
Tc'
development
100
LIMITATIONS:
I. Maximum length = 1000 Feet
90 2. Maximum area = 10 Acres
80
70
60
50
0
0
35
a
0
30
U)
25
c_
E
concentration
c 20
19
18
17
16
15
14
13
12
w
0
4)
E
II
10
Pi Development
9 80- Apartment
75- Mobile Home
65- Condominium
60- Single Family -5,000 ft2 Lot
7 40 - Single Family -I/4 Acre Lot
20 Single Family -I Acre Lot
6 15 - Developed Open Space
10 - Single Family -2 1/2 Acre Lot
EXAMPLE:
5 ( I ) L= 550',
Development,
K
Undeveloped
Good Cover
Undeveloped
Fair Cover
Undeveloped
Poor Cover
Single Family
(5-7 DU/AC)
Commercial
(Paved)
8
a
H
u — 500
400
.4-.`a ^ 300
at 0
ap4E
E O "c
a
Pi1)1
0
— 200
100
80
60
40
30
20
�-- 10
8
6
4
— 3
— 2
Tc
5
(mm)
6
7
8
9
I0
II
12
1.0 13
= .8
6 / 14
_ - .4
— .3 .2) 15
'2 16
� iY 17
18
b$90'E 19
KEY 20
L - H-Tc-K-Tc'
c
0 c
20 0
m
m
w
4
ORANGE COUNTY
HYDROLOGY MANUAL
H:5.0', K=Single Family (5-7 DU/AC)
Tc=12.6 min.
(2) L= 550', H= 5.0', K= Commercial
Development, Tc=9.7 min.
25
30
35
40
Family Development (5-7 ou/AC)
m
c
in
TIME OF CONCENTRATION
NOMOGRAPH
FOR INITIAL SUBAREA
D-4
Figure D-1
When the flow is concentrated in curb and gutters, drainage channels or
conduits, the flow velocity may be estimated by the well-known Manning's
equation
where
V_ 1.49
n
2/31/2
V = mean velocity (fps)
(D.2)
n = Manning coefficient of roughness (see Design
Manual)
R = hydraulic radius (feet)
S = energy slope which equals the conduit invert
slope for uniform flow
The travel time will then be the flow distance divided by the velocity of flow.
Computations of travel time through subareas which continually add to the
peak flow (e.g., streetflow) should be based on the average peak flow through
the subarea. This average peak flow is generally a simple average of the
peak flow rates estimated at the upstream and downstream points of the
subarea.
The initial subarea Tc estimation often is the most significant factor leading
to the Tc computation of a watershed. Small development studies typically
utilize only initial subarea estimations due to the small subarea sizes. Larger
study areas generally show high sensitivity to the initial subarea Tc.
Consequently, judgment is needed when developing initial subarea Tc esti-
mates. The nomograph of Figure D -I is based on the Kirpich formula and
relates an initial subarea Tc to subarea slope and development type. It is
assumed in the nomograph that overland flow effects dominate the travel
time hydraulics.
It is noted that the Tc computation procedure is based upon the summation of
an initial subarea time of concentration with the several travel times
estimated by normal depth flow -velocities through subsequent subareas.
D.4. INTENSITY -DURATION CURVES
The precipitation intensity -duration curves presented in Section 13.3
(Figures B-3 and 13-4) are appropriate for the rational method.
E .S. RUNOFF COEFFICIENT
The runoff coefficient (C) is the ratio of rate of runoff to the rate of
rainfall at an average intensity (I) when the total drainage area is contribut-
ing. The selection of the runoff coefficient depends on rainfall intensity, soil
infiltration rate (F ), and impervious and pervious area fractions (ai and ap).
Since one acre-inch/hour is equal to 1.008 cfs, the rational formula is
generally assumed to estimate a peak flowrate in cfs. Runoff coefficient
curves are developed using the relationship:
(I -
_E.)for I greater than Fp•
_ (0.90 (al + ,
_
0.90 ai, for I less than or equal to Fp
(D.3)
where the proportion factor of 0.90 is a calibration constant determined by
an average fit between the rational method and design storm unit hydrograph
(see Section E) peak flow rate estimates, and where
C = runoff coefficient
I = rainfall intensity (inches/hour)
Fp = infiltration rate for pervious areas (inches/hour)
(see Section C.6.4)
a; ratio of impervious area to total area (decimal
fraction)
ap _ ratio of pervious area to total area (dec:imal
fraction), (ap = I - a1)
D-6
Sub-Area Area Imp
Length
(Feet)
H
(Feet)
Tc
(Min)
I (2-year)
(in/hr)
I (100-year)
(in/hr)C Q (2-year)
(cfs)
Q (100-year)
(cfs)
A1 2.04 0.01 280 2 13.5 1.28 3.50 0.69 1.80 4.94
A2 0.46 0.01 112 3 7.25 1.83 5.00 0.75 0.63 1.73
Total 2.44 6.67
Sub-Area Area Imp
Length
(Feet)
H
(Feet)
Tc
(Min)
I (2-year)
(in/hr)
I (100-year)
(in/hr)C Q (2-year)
(cfs)
Q (100-year)
(cfs)
A1 1.02 0.8 205 2.5 6.5 1.95 5.32 0.87 1.73 4.74
A2 0.58 1 50 1 4.75 2.33 6.37 0.90 1.22 3.33
A3 0.46 0.22 110 0.5 8.9 1.63 4.45 0.77 0.58 1.58
A4 0.22 0.41 220 1 10.5 1.48 4.04 0.79 0.26 0.70
A5 0.22 0.29 200 1 10.5 1.48 4.04 0.77 0.25 0.69
Total 4.03 11.03
Pre-Development Hydrologic Summary Table
Post-Development Hydrologic Summary Table
PRE-DEVELOPMENT AREA A1
Tc' = 13.5 MIN
PRE-DEVELOPMENT AREA A2
Tc' =
7.25
MIN
POST-DEVELOPMENT AREA A1
Tc' = 6.5 MIN
POST-DEVELOPMENT AREA A2
Tc' = 4.75 MIN
POST-DEVELOPMENT AREA A3
Tc' = 8.9 MIN
POST-DEVELOPMENT AREA A4
Tc' = 10.5 MIN
POST-DEVELOPMENT AREA A5
Tc' = 10.5 MIN
APPENDIX C
Supporting Documents
PROJECT SITE
SOIL GROUP B
APPENDIX D
FEMA Flood Map
National Flood Hazard Layer FIRMette
0 500 1,000 1,500 2,000250
Feet
Ü
SEE FIS REPORT FOR DETAILED LEGEND AND INDEX MAP FOR FIRM PANEL LAYOUT
SPECIAL FLOOD
HAZARD AREAS
Without Base Flood Elevation (BFE)
Zone A, V, A99
With BFE or DepthZone AE, AO, AH, VE, AR
Regulatory Floodway
0.2% Annual Chance Flood Hazard, Areas
of 1% annual chance flood with average
depth less than one foot or with drainage
areas of less than one square mileZone X
Future Conditions 1% Annual
Chance Flood HazardZone X
Area with Reduced Flood Risk due to
Levee. See Notes.Zone X
Area with Flood Risk due to LeveeZone D
NO SCREEN Area of Minimal Flood Hazard Zone X
Area of Undetermined Flood HazardZone D
Channel, Culvert, or Storm Sewer
Levee, Dike, or Floodwall
Cross Sections with 1% Annual Chance
17.5 Water Surface Elevation
Coastal Transect
Coastal Transect Baseline
Profile Baseline
Hydrographic Feature
Base Flood Elevation Line (BFE)
Effective LOMRs
Limit of Study
Jurisdiction Boundary
Digital Data Available
No Digital Data Available
Unmapped
This map complies with FEMA's standards for the use of
digital flood maps if it is not void as described below.
The basemap shown complies with FEMA's basemap
accuracy standards
The flood hazard information is derived directly from the
authoritative NFHL web services provided by FEMA. This map
was exported on 12/9/2022 at 6:52 PM and does not
reflect changes or amendments subsequent to this date and
time. The NFHL and effective information may change or
become superseded by new data over time.
This map image is void if the one or more of the following map
elements do not appear: basemap imagery, flood zone labels,
legend, scale bar, map creation date, community identifiers,
FIRM panel number, and FIRM effective date. Map images for
unmapped and unmodernized areas cannot be used for
regulatory purposes.
Legend
OTHER AREAS OF
FLOOD HAZARD
OTHER AREAS
GENERAL
STRUCTURES
OTHER
FEATURES
MAP PANELS
8
B 20.2
The pin displayed on the map is an approximate
point selected by the user and does not represent
an authoritative property location.
1:6,000
117°57'26"W 33°52'26"N
117°56'49"W 33°51'56"N
Basemap: USGS National Map: Orthoimagery: Data refreshed October, 2020
APPENDIX E
Hydraulic Calculations
Parkway Drain
Project Description
Manning
FormulaFriction Method
Normal DepthSolve For
Input Data
0.013Roughness Coefficient
%2.0Channel Slope
in4.0Height
in42.00Bottom Width
cfs5.52Discharge
Results
in3.1Normal Depth
ft²0.9Flow Area
in48.3Wetted Perimeter
in2.7Hydraulic Radius
in42.00Top Width
in4.0Critical Depth
%78.5Percent Full
%1.0Critical Slope
ft/s6.03Velocity
ft0.56Velocity Head
ft0.83Specific Energy
2.077Froude Number
cfs5.38Discharge Full
%2.0Slope Full
SupercriticalFlow Type
GVF Input Data
in0.0Downstream Depth
in0.0Length
0Number Of Steps
GVF Output Data
in0.0Upstream Depth
N/AProfile Description
ft0.00Profile Headloss
%0.0Average End Depth Over Rise
%78.5Normal Depth Over Rise
ft/sInfinityDownstream Velocity
ft/sInfinityUpstream Velocity
in3.1Normal Depth
in4.0Critical Depth
%2.0Channel Slope
%1.0Critical Slope
Page 1 of 127 Siemon Company Drive Suite 200 W
Watertown, CT 06795 USA +1-203-755-1666
12/12/2022
FlowMaster
[10.03.00.03]
Bentley Systems, Inc. Haestad Methods Solution
CenterUntitled1.fm8
Street Spread - 2yr
Project Description
SpreadSolve For
Input Data
%0.2Channel Slope
cfs4.03Discharge
ft2.0Gutter Width
%5.0Gutter Cross Slope
%3.2Road Cross Slope
0.013Roughness Coefficient
Results
ft11.2Spread
ft²2.0Flow Area
in4.7Depth
in0.4Gutter Depression
ft/s1.98Velocity
Page 1 of 127 Siemon Company Drive Suite 200 W
Watertown, CT 06795 USA +1-203-755-1666
12/12/2022
FlowMaster
[10.03.00.03]
Bentley Systems, Inc. Haestad Methods Solution
CenterUntitled1.fm8
Street Spread - 100 Yr
Project Description
SpreadSolve For
Input Data
%0.2Channel Slope
cfs11.03Discharge
ft2.0Gutter Width
%5.0Gutter Cross Slope
%3.2Road Cross Slope
0.013Roughness Coefficient
Results
ft16.4Spread
ft²4.4Flow Area
in6.7Depth
in0.4Gutter Depression
ft/s2.53Velocity
Page 1 of 127 Siemon Company Drive Suite 200 W
Watertown, CT 06795 USA +1-203-755-1666
12/12/2022
FlowMaster
[10.03.00.03]
Bentley Systems, Inc. Haestad Methods Solution
CenterUntitled1.fm8
W = 2'
L = 3'
A = 6 ft2
A = 3 ft2 (50% clogging)
Q=11.03 CFS
0.43 FT
Preliminary Water Quality
Management Plan
(WQMP)
Project Name:
Pointe Common
1600 West Commonwealth Avenue,
Fullerton, CA 92833
Prepared for:
Meta Housing Corporation
11150 W. Olympic Blvd., Suite 620
Los Angeles, CA 90064
310-575-3543
Prepared by:
DK Engineer Corp (DKE)
Engineer ___Matt Plourde___ Registration No.___84893___
6420 Wilshire Blvd., Suite 1000
Los Angeles, CA 90048
(909) 559-7361
Prepared:
December 2022
Water Quality Management Plan (WQMP)
Pointe Common
Meta Housing Corp. Owner’s Certification
Project Owner’s Certification
Permit/Application No. PRJ-2022-0121 Grading Permit No.
Tract/Parcel Map No. Building Permit No.
CUP, SUP, and/or APN (Specify Lot Numbers if Portions of Tract) APN 030-290-22
This Water Quality Management Plan (WQMP) has been prepared for Meta Housing
Corporation by DK Engineer Corp (DKE). The WQMP is intended to comply with the
requirements of the local NPDES Stormwater Program requiring the preparation of the plan.
The undersigned, while it owns the subject property, is responsible for the implementation of
the provisions of this plan and will ensure that this plan is amended as appropriate to reflect
up-to-date conditions on the site consistent with the current Orange County Drainage Area
Management Plan (DAMP) and the intent of the non-point source NPDES Permit for Waste
Discharge Requirements for the County of Orange, Orange County Flood Control District and
the incorporated Cities of Orange County within the Fullerton Region. Once the undersigned
transfers its interest in the property, its successors-in-interest shall bear the aforementioned
responsibility to implement and amend the WQMP. An appropriate number of approved and
signed copies of this document shall be available on the subject site in perpetuity.
Owner:
Title Pointe Common
Company Meta Housing Corp, Chris Maffris, SVP
Address 11150 W. Olympic Blvd, Suite 620 , Los Angeles, CA 90064
Email
Telephone #
Signature Date
Water Quality Management Plan (WQMP)
Pointe Common
Meta Housing Corp. Owner’s Certification
Contents Page No.
Section I Discretionary Permit(s) and Water Quality Conditions ..................................... 3
Section II Project Description .......................................................................................... 4
Section III Site Description ........................................................................................... 10
Section IV Best Management Practices (BMPs) ............................................................. 12
Section V Inspection/Maintenance Responsibility for BMPs .......................................... 24
Section VI Site Plan and Drainage Plan ......................................................................... 26
Section VII Educational Materials .................................................................................. 27
Attachments
Attachment A . ................................................................................. Educational Materials
Attachment B……………………………………………………………………. Supporting Figures
Attachment C……………………………………………………………………. Geotechnical Report
Attachment D………………………………………………………………. Design Plans and Details
Water Quality Management Plan (WQMP)
Pointe Common
Meta Housing Corp. Section I
Preliminary WQMP October 2022 Page 3
Section I Discretionary Permit(s) and
Water Quality Conditions
Provide discretionary permit and water quality information. Refer to Section 2.1 in the Technical
Guidance Document (TGD) available from the Orange County Stormwater Program (ocwatersheds.com).
Project Infomation
Permit/Application No. PRJ-2022-0121 Tract/Parcel Map
No./APN 030-290-22
Additional Information/
Comments:
Water Quality Conditions
Water Quality
Conditions
(list verbatim)
A Water Quality Management Plan is required for this project.
Watershed-Based Plan Conditions
Provide applicable
conditions from watershed
- based plans including
WIHMPs and TMDLS.
To be determined on Final WQMP.
Water Quality Management Plan (WQMP)
Pointe Common
Meta Housing Corp. Section III
Preliminary WQMP December 2022 Page 4
Section II Project Description
II.1 Project Description
Provide a detailed project description including:
· Project areas;
· Land uses;
· Land cover;
· Design elements;
· A general description not broken down by drainage management areas (DMAs).
Include attributes relevant to determining applicable source controls. Refer to Section 2.2 in the TGD
for information that must be included in the project description.
Description of Proposed Project
Development Category
(Verbatim from WQMP):
Project Area (ft2): 108,200 ft2 Number of Dwelling Units: ___65___ SIC Code: __________
Narrative Project
Description:
The project consists of the construction of three stories of residential
units. The unit count includes 62 residential units. The site is 2.5 acres
and located at 1600 West Commonwealth Avenue in the City of
Fullerton.
Project Area
Pervious Impervious
Area
(acres or sq ft)
Percentage
Area
(acres or sq ft)
Percentage
Pre-Project Conditions 107,607 sq ft 99.0% 1,087 sq ft 1.0%
Post-Project Conditions 32,053 sq ft 29.5% 76,641 sq ft 70.5%
Drainage
Patterns/Connections
All roof drainage will be collected using downspouts and will flow first into one
of the two on-site CDS units. After being filtered by the CDS unit, water will
flow into one of two infiltration trenches. Storm water will then be infiltrated
into the surrounding soil. If needed, water will overflow through the CDS units
Water Quality Management Plan (WQMP)
Pointe Common
Meta Housing Corp. Section III
Preliminary WQMP December 2022 Page 5
into a catch basin, which will then discharge through a curb drain. No pump
will be needed for overflow purposes.
This existing developed site slopes from the south to the north side of the site
and the runoff sheet flows off the site towards Commonwealth Avenue.
II.2 Potential Stormwater Pollutants
Determine and list expected stormwater pollutants based on land uses and site activities. Refer to
Section 2.2.2 and Table 2.1 in the TGD for guidance.
Pollutants of Concern
Pollutant
Circle One:
E=Expected to
be of concern
N=Not Expected
to be of concern
Additional Information and Comments
Suspended-Solid/ Sediment E N
Nutrients E N
Heavy Metals E N
Pathogens (Bacteria/Virus) E N
Pesticides E N
Oil and Grease E N
Toxic Organic Compounds E N
Trash and Debris E N
Water Quality Management Plan (WQMP)
Pointe Common
Meta Housing Corp. Section III
Preliminary WQMP December 2022 Page 6
II.3 Hydrologic Conditions of Concern
Determine if streams located downstream from the project area are determined to be potentially
susceptible to hydromodification impacts. Refer to Section 2.2.3.1 in the TGD for NOC or Section
2.2.3.2 for <SOC>.
No – Show map
Yes – Describe applicable hydrologic conditions of concern below. Refer to Section 2.2.3 in the
TGD.
Water Quality Management Plan (WQMP)
Pointe Common
Meta Housing Corp. Section III
Preliminary WQMP December 2022 Page 7
II.4 Post Development Drainage Characteristics
Describe post development drainage characteristics. Refer to Section 2.2.4 in the TGD.
All roof drainage will be collected using downspouts and will flow first into one of the two on-site CDS units.
After being filtered by the CDS unit, water will flow into one of two infiltration trenches. Storm water will then
be infiltrated into the surrounding soil. If needed, water will overflow through the CDS units into a catch basin,
which will then discharge through a curb drain. No pump will be needed for overflow purposes.
Runoff from grade level courtyards will be captured by area drains and directed by storm-drain pipe to a pump
located either at the basement or outside of the proposed building and pumped to the infiltration trench.
II.5 Property Ownership/Management
Describe property ownership/management. Refer to Section 2.2.5 in the TGD.
To be added in the Final WQMP
Water Quality Management Plan (WQMP)
Pointe Common
Meta Housing Corp. Section III
Preliminary WQMP December 2022 Page 8
Section III Site Description
III.1 Physical Setting
Fill out table with relevant information. Refer to Section 2.3.1 in the TGD.
Planning Area/
Community Name
Manufacturing - General
Location/Address 1600 West Commonwealth Avenue
Fullerton, CA 92833
Project Area Description The project area is a mixed-use area. To the west and south of the
site are railroad tracks. To the north and east of the site are
residential and commercial buildings respectively.
Land Use The project site is currently an undeveloped lot, approximately 2.5
acres.
Zoning M-G (Manufacturing – General)
Acreage 2.5 acres
Predominant Soil Type B Soils
Water Quality Management Plan (WQMP)
Pointe Common
Meta Housing Corp. Section III
Preliminary WQMP December 2022 Page 9
III.2 Site Characteristics
Fill out table with relevant information and include information regarding BMP sizing, suitability, and
feasibility, as applicable. Refer to Section 2.3.2 in the TGD.
Precipitation Zone 0.90”, Per Rainfall Zone Map XVI-1
Topography There is some sloping on-site, with approximately 2’-3’ of difference
in elevation across site.
Drainage
Patterns/Connections
Site slopes from the south to north of the site and sheet flows off the
site towards Commonwealth Avenue.
Soil Type, Geology, and
Infiltration Properties
Infiltration is viable on-site. Testing was done using the County
Method and gave a measured infiltration rate of 6 in/hr on the
western area of the site and 1.5 in /hr on the eastern area of the site.
Site Characteristics (continued)
Hydrogeologic
(Groundwater) Conditions
Per Geotechnical Report by GeoConcepts. Inc., dated August 23, 2022,
groundwater level is approximately 42’ below the surface of site.
Geotechnical Conditions
(relevant to infiltration) Soil suitable for infiltration per geotechnical report.
Off-Site Drainage The adjacent streets drain by non-erosive methods to City storm drain inlets.
Utility and Infrastructure
Information
There is an existing City storm drain line in West Commonwealth Avenue
adjacent to the site.
Water Quality Management Plan (WQMP)
Pointe Common
Meta Housing Corp. Section III
Preliminary WQMP December 2022 Page 10
III.3 Watershed Description
Fill out table with relevant information and include information regarding BMP sizing, suitability,
and feasibility, as applicable. Refer to Section 2.3.3 in the TGD.
Receiving Waters Will be determined During the final WQMP preparation.
303(d) Listed Impairments Will be determined During the final WQMP preparation.
Applicable TMDLs Will be determined During the final WQMP preparation.
Pollutants of Concern for
the Project Will be determined During the final WQMP preparation.
Environmentally Sensitive
and Special Biological
Significant Areas
Will be determined During the final WQMP preparation.
Water Quality Management Plan (WQMP)
Pointe Common
Meta Housing Corp. Section IV
Preliminary WQMP December 2022 Page 11
Section IV Best Management Practices (BMPs)
IV. 1 Project Performance Criteria
Describe project performance criteria. Several steps must be followed in order to determine what
performance criteria will apply to a project. These steps include:
· If the project has an approved WIHMP or equivalent, then any watershed specific criteria
must be used and the project can evaluate participation in the approved regional or sub-
regional opportunities. The local Permittee planning or NPDES staff should be consulted
regarding the existence of an approved WIHMP or equivalent.
· Determine applicable hydromodification control performance criteria. Refer to Section 7.II-
2.4.2.2 of the Model WQMP.
· Determine applicable LID performance criteria. Refer to Section 7.II-2.4.3 of the Model WQMP.
· Determine applicable treatment control BMP performance criteria. Refer to Section 7.II-3.2.2 of
the Model WQMP.
· Calculate the LID design storm capture volume for the project. Refer to Section 7.II-2.4.3 of the
Model WQMP.
(NOC Permit Area only) Is there an approved WIHMP or equivalent
for the project area that includes more stringent LID feasibility
criteria or if there are opportunities identified for implementing LID
on regional or sub-regional basis?
YES NO
If yes, describe WIHMP
feasibility criteria or
regional/sub-regional LID
opportunities.
Water Quality Management Plan (WQMP)
Pointe Common
Meta Housing Corp. Section IV
Preliminary WQMP December 2022 Page 12
Project Performance Criteria (continued)
If HCOC exists,
list applicable
hydromodification
control
performance
criteria (Section
7.II-2.4.2.2 in
MWQMP)
No HCOC
List applicable LID
performance
criteria (Section
7.II-2.4.3 from
MWQMP)
Priority Projects must infiltrate, harvest and use, evapotranspire, or biotreat/biofilter,
the 85th percentile, 24-hour storm event (Design Capture Volume). •
A properly designed biotreatment system may only be considered if infiltration,
harvest and use, and evapotranspiration (ET) cannot be feasibly implemented for the
full design capture volume. In this case, infiltration, harvest and use, and ET practices
must be implemented to the greatest extent feasible and biotreatment may be
provided for the remaining design capture volume.
List applicable
treatment control
BMP performance
criteria (Section
7.II-3.2.2 from
MWQMP)
Infiltration will be utilized onsite to treat stormwater. Stormwater will be routed into
two infiltration trenches.
Calculate LID
design storm
capture volume
for Project.
Total Site
C=%Imp * .75 + .15
Total Treatment Area = 108694 SF (2.5 Acres)
C= .705 x .75 + .15 -= .68
DCV = C*d*A = 0.68*0.90in*1/12*108,694 = 5,543 ft3
Water Quality Management Plan (WQMP)
Pointe Common
Meta Housing Corp. Section IV
Preliminary WQMP December 2022 Page 13
IV.2. SITE DESIGN AND DRAINAGE PLAN
Describe site design and drainage plan including
· A narrative of site design practices utilized or rationale for not using practices;
· A narrative of how site is designed to allow BMPs to be incorporated to the MEP
· A table of DMA characteristics and list of LID BMPs proposed in each DMA.
· Reference to the WQMP plot plan.
· Calculation of Design Capture Volume (DCV) for each drainage area.
· A listing of GIS coordinates for LID and Treatment Control BMPs (unless not required by
local jurisdiction).
Refer to Section 2.4.2 in the TGD.
All roof drainage will be collected using downspouts and will flow first into one of the two on-site CDS units.
After being filtered by the CDS unit, water will flow into one of two infiltration trenches. Storm water will then
be infiltrated into the surrounding soil. If needed, water will overflow through the CDS units into a catch basin,
which will then discharge through a curb drain. No pump will be needed for overflow purposes.
Water Quality Management Plan (WQMP)
Pointe Common
Meta Housing Corp. Section IV
Preliminary WQMP December 2022 Page 14
IV.3 LID BMP SELECTION AND PROJECT CONFORMANCE ANALYSIS
Each sub-section below documents that the proposed design features conform to the applicable
project performance criteria via check boxes, tables, calculations, narratives, and/or references to
worksheets. Refer to Section 2.4.2.3 in the TGD for selecting LID BMPs and Section 2.4.3 in the TGD for
conducting conformance analysis with project performance criteria.
IV.3.1 Hydrologic Source Controls
If required HSCs are included, fill out applicable check box forms. If the retention criteria are
otherwise met with other LID BMPs, include a statement indicating HSCs not required.
Name Included?
Localized on-lot infiltration
Impervious area dispersion (e.g. roof top
disconnection)
Street trees (canopy interception)
Residential rain barrels (not actively managed)
Green roofs/Brown roofs
Blue roofs
Impervious area reduction (e.g. permeable
pavers, site design)
Other: HSC not required
Other:
Other:
Other:
Other:
Other:
Other:
Other:
Water Quality Management Plan (WQMP)
Pointe Common
Meta Housing Corp. Section IV
Preliminary WQMP December 2022 Page 15
IV.3.2 Infiltration BMPs
Identify infiltration BMPs to be used in project. If design volume cannot be met state why BMPs
cannot be met
Name Included?
Bioretention without underdrains
Rain gardens
Porous landscaping
Infiltration planters
Retention swales
Infiltration trenches
Infiltration basins
Drywells
Subsurface infiltration galleries
French drains
Permeable asphalt
Permeable concrete
Permeable concrete pavers
Other:
Other:
Show calculations below to demonstrate if the LID Design Strom Capture Volume can be met with
infiltration BMPs. If not document how much can be met with infiltration and document why it is
not feasible to meet the full volume with infiltration BMPs.
DCV = 5,543 CF (per section IV.1)
East Parking Lot Trench (Treats 70% of Site)
DCV= 5,543 CF * 0.7 = 3,880 CF
Trench Volume = 3,944 CF (See Contech Detail)
Trench Footprint = 73 ft x 18.5 ft = 1,350.5 SF
Kobserved= 1.5 in/hr, FS= 2
Kdesign=.75 in/hr
Drawdown Time = 3,944 CF / (1,350.5 * 0.75/12) = 46.73 Hours
Water Quality Management Plan (WQMP)
Pointe Common
Meta Housing Corp. Section IV
Preliminary WQMP December 2022 Page 16
Western Lot Trench (Treats 30% of Site)
DCV= 5,543 CF * 0.3 = 1,663 CF
Trench Volume = 1,672 CF (See Contech Detail)
Trench Footprint = 61 ft x 9.5 ft = 579.5 SF
Kobserved= 6 in/hr, FS= 2
Kdesign=3 in/hr
Drawdown Time = 1,672 CF / (579.5 * 3/12) = 11.54 Hours
See Appendix C for Infiltration Report
IV.3.3 Evapotranspiration, Rainwater Harvesting BMPs
If the full Design Storm Capture Volume cannot be met with infiltration BMPs, describe any
evapotranspiration, rainwater harvesting BMPs.
Name Included?
All HSCs; See Section IV.3.1
Surface-based infiltration BMPs
Biotreatment BMPs
Above-ground cisterns and basins
Underground detention
Other:
Other:
Other:
Water Quality Management Plan (WQMP)
Pointe Common
Meta Housing Corp. Section IV
Preliminary WQMP December 2022 Page 17
Show calculations below to demonstrate if the LID Design Strom Capture Volume can be met with
evapotranspiration, rainwater harvesting BMPs in combination with infiltration BMPs. If not
document how much can be met with either infiltration BMPs, evapotranspiration, rainwater
harvesting BMPs, or a combination, and document why it is not feasible to meet the full volume
with either of these BMPs categories.
Due to not meeting minimum TUTIA requirements or minimum Irrigation Area Thresholds, rainwater
harvesting is not feasible for this site. See below for calculations.
TUTIA
Design Capture Storm Depth = .9 in
Project Type = Residential
Minimum Required TUTIA Ratio = 110
Toilet Users/Impervious Acres = 109 users/ 1.95 ac =56
Irrigation Area Thresholds
Design Capture Storm Depth = .9 in
Min. Req. Irrigation Area per Tributary Impervious Acre =1.01 Ac/Ac
Proposed Irrigation Area = .55 ac
Proposed Impervious Area = 1.95 ac
.55/1.95 = .282 < 1.01
IV.3.4 Biotreatment BMPs
If the full Design Storm Capture Volume cannot be met with infiltration BMPs, and/or
evapotranspiration and rainwater harvesting BMPs, describe biotreatment BMPs. Include sections
for selection, suitability, sizing, and infeasibility, as applicable.
Name Included?
Bioretention with underdrains
Stormwater planter boxes with underdrains
Rain gardens with underdrains
Constructed wetlands
Vegetated swales
Vegetated filter strips
Water Quality Management Plan (WQMP)
Pointe Common
Meta Housing Corp. Section IV
Preliminary WQMP December 2022 Page 18
Proprietary vegetated biotreatment systems
Wet extended detention basin
Dry extended detention basins
Other:
Other:
Show calculations below to demonstrate if the LID Design Strom Capture Volume can be met with
infiltration, evapotranspiration, rainwater harvesting and/or biotreatment BMPs. If not document
how much can be met with either infiltration BMPs, evapotranspiration, rainwater harvesting
BMPs, or a combination, and document why it is not feasible to meet the full volume with either of
these BMPs categories.
See section IV.3.2 for infiltation calculations
Water Quality Management Plan (WQMP)
Pointe Common
Meta Housing Corp. Section IV
Preliminary WQMP December 2022 Page 19
IV.3.5 Hydromodification Control BMPs
Describe hydromodification control BMPs. See Section 5 TGD. Include sections for selection,
suitability, sizing, and infeasibility, as applicable. Detail compliance with Prior Conditions of
Approval.
Hydromodification Control BMPs
BMP Name BMP Description
Water Quality Management Plan (WQMP)
Pointe Common
Meta Housing Corp. Section IV
Preliminary WQMP December 2022 Page 20
IV.3.6 Regional/Sub-Regional LID BMPs
Describe regional/sub-regional LID BMPs in which the project will participate. Refer to Section 7.II-
2.4.3.2 of the Model WQMP.
Regional/Sub-Regional LID BMPs
None
Water Quality Management Plan (WQMP)
Pointe Common
Meta Housing Corp. Section IV
Preliminary WQMP December 2022 Page 21
IV.3.7 Treatment Control BMPs
Treatment control BMPs can only be considered if the project conformance analysis indicates that it is not
feasible to retain the full design capture volume with LID BMPs. Describe treatment control BMPs including
sections for selection, sizing, and infeasibility, as applicable.
Treatment Control BMPs
BMP Name BMP Description
Water Quality Management Plan (WQMP)
Pointe Common
Meta Housing Corp. Section IV
Preliminary WQMP December 2022 Page 22
IV.3.8 Non-structural Source Control BMPs
Fill out non-structural source control check box forms or provide a brief narrative explaining if non-
structural source controls were not used.
Non-Structural Source Control BMPs
Identifier Name
Check One
If not applicable, state brief
reason Included Not
Applicable
N1 Education for Property Owners,
Tenants and Occupants
N2 Activity Restrictions
N3 Common Area Landscape
Management
N4 BMP Maintenance
N5 Title 22 CCR Compliance (How
development will comply)
N6 Local Industrial Permit Compliance N/A
N7 Spill Contingency Plan
N8 Underground Storage Tank
Compliance N/A
N9 Hazardous Materials Disclosure
Compliance N/A
N10 Uniform Fire Code Implementation
N11 Common Area Litter Control
N12 Employee Training
N13 Housekeeping of Loading Docks No loading docks on project
N14 Common Area Catch Basin Inspection
N15 Street Sweeping Private Streets and
Parking Lots
Not private street or parking
lots on project.
N16 Retail Gasoline Outlets N/A
Water Quality Management Plan (WQMP)
Pointe Common
Meta Housing Corp. Section IV
Preliminary WQMP December 2022 Page 23
IV.3.9 Structural Source Control BMPs
Fill out structural source control check box forms or provide a brief narrative explaining if
Structural source controls were not used.
Structural Source Control BMPs
Identifier Name
Check One
If not applicable, state brief
reason Included Not
Applicable
S1 Provide storm drain system stenciling
and signage
S2
Design and construct outdoor material
storage areas to reduce pollution
introduction
S3
Design and construct trash and waste
storage areas to reduce pollution
introduction
S4
Use efficient irrigation systems &
landscape design, water conservation,
smart controllers, and source control
S5 Protect slopes and channels and
provide energy dissipation
Incorporate requirements applicable to
individual priority project categories
(from SDRWQCB NPDES Permit)
S6 Dock areas
S7 Maintenance bays
S8 Vehicle wash areas
S9 Outdoor processing areas
S10 Equipment wash areas
S11 Fueling areas
S12 Hillside landscaping No hillside area on site
S13 Wash water control for food
preparation areas N/A
S14 Community car wash racks Car wash on premises not
permitted.
Water Quality Management Plan (WQMP)
Pointe Common
Meta Housing Corp. Section IV
Preliminary WQMP December 2022 Page 24
IV.4 ALTERNATIVE COMPLIANCE PLAN (IF APPLICABLE)
IV.4.1 Water Quality Credits
Determine if water quality credits are applicable for the project. Refer to Section 3.1 of the Model
WQMP for description of credits and Appendix VI of the TGD for calculation methods for applying water
quality credits.
Description of Proposed Project
Project Types that Qualify for Water Quality Credits (Select all that apply):
Redevelopment
projects that reduce the
overall impervious
footprint of the project
site.
Brownfield redevelopment, meaning
redevelopment, expansion, or reuse of real
property which may be complicated by the
presence or potential presence of hazardous
substances, pollutants or contaminants, and
which have the potential to contribute to
adverse ground or surface WQ if not
redeveloped.
Higher density development projects which
include two distinct categories (credits can only
be taken for one category): those with more than
seven units per acre of development (lower credit
allowance); vertical density developments, for
example, those with a Floor to Area Ratio (FAR)
of 2 or those having more than 18 units per acre
(greater credit allowance).
Mixed use development, such as a
combination of residential, commercial,
industrial, office, institutional, or other land
uses which incorporate design principles
that can demonstrate environmental benefits
that would not be realized through single
use projects (e.g. reduced vehicle trip traffic
with the potential to reduce sources of water
or air pollution).
Transit-oriented developments, such as a mixed
use residential or commercial area designed to
maximize access to public transportation; similar to
above criterion, but where the development center is
within one half mile of a mass transit center (e.g. bus,
rail, light rail or commuter train station). Such
projects would not be able to take credit for both
categories, but may have greater credit assigned
Redevelopment
projects in an established
historic district, historic
preservation area, or
similar significant city
area including core City
Center areas (to be
defined through
mapping).
Developments with
dedication of undeveloped
portions to parks,
preservation areas and
other pervious uses.
Developments
in a city center
area.
Developments
in historic
districts or
historic
preservation
areas.
Live-work developments, a
variety of developments designed
to support residential and
vocational needs together –
similar to criteria to mixed use
development; would not be able
to take credit for both categories.
In-fill projects, the
conversion of empty lots
and other underused
spaces into more
beneficially used spaces,
such as residential or
commercial areas.
Calculation of
Water Quality
Credits
(if applicable)
The entire DCV is being treated by LID BMPs. Water quality credits will not be used.
Water Quality Management Plan (WQMP)
Pointe Common
Meta Housing Corp. Section IV
Preliminary WQMP December 2022 Page 25
IV.4.2 Alternative Compliance Plan Information
Describe an alternative compliance plan (if applicable). Include alternative compliance obligations
(i.e., gallons, pounds) and describe proposed alternative compliance measures. Refer to Section 7.II
3.0 in the WQMP.
N/A
Water Quality Management Plan (WQMP)
Pointe Common
Meta Housing Corp. Section III
Preliminary WQMP October 2022 Page 26
Section V Inspection/Maintenance
Responsibility for BMPs
Fill out information in table below. Prepare and attach an Operation and Maintenance Plan.
Identify the mechanism through which BMPs will be maintained. Inspection and maintenance
records must be kept for a minimum of five years for inspection by the regulatory agencies. Refer to
Section 7.II 4.0 in the Model WQMP.
BMP Inspection/Maintenance
BMP Reponsible
Party(s)
Inspection/ Maintenance
Activities Required
Minimum
Frequency of
Activities
Infiltration
Trench
To be
determined
Infiltration trench
inspection/maintenance will consist
of the following:
1. The condition of the unit will
be checked after the first
several runoff events after
installation. The visual
inspection will ascertain that
the unit is functioning
properly (no blockages or
obstructions to inlet and/or
separation screen),
measuring the amount of
solid materials that have
accumulated in the sump, the
amount of fine sediment
accumulated behind the
screen, and determining the
amount of floating trash and
debris in the separation
chamber.
2. Floatables will be removed and
the sump cleaned when the
sump is above 75%-85% full of
solids. At least once a year, the
unit will be pumped down and
the screen inspected for
1. Inspect before and
after storm events.
2. Inspect a minimum of
two times a year. Check
overflow and curb
drains are free of debris
and clogs.
3. If standing water is
observed 48 hours after
a storm event, excavate
and replace the top 12”
of draining soil
constituting the
filtration area.
Water Quality Management Plan (WQMP)
Pointe Common
Meta Housing Corp. Section III
Preliminary WQMP October 2022 Page 27
damage and to ensure that it is
properly fastened. If the screen
is damaged, it will be replaced
or repaired.
3. Legibility of stencils and/or
signs at all storm drain inlets
and catch basins within the
project area must be
maintained at all time.
4. Maintain a log of all inspections
and maintenance performed on
the CDS unit.
BMP Inspection/Maintenance
BMP Reponsible
Party(s)
Inspection/
Maintenance
Activities
Required
Minimum
Frequency of
Activities
Water Quality Management Plan (WQMP)
Pointe Common
Meta Housing Corp. Section III
Preliminary WQMP October 2022 Page 28
Water Quality Management Plan (WQMP)
Pointe Common
Meta Housing Corp. Section III
Preliminary WQMP October 2022 Page 29
Section VI Site Plan and Drainage Plan
See attached 30”x42” Grading Plan (site plan) C1.30
See attached 30”x42” Utility Plan C1.40
VI.1 SITE PLAN AND DRAINAGE PLAN
Include a site plan and drainage plan sheet set containing the following minimum information:
· Project location
· Site boundary
· Land uses and land covers, as applicable
· Suitability/feasibility constraints
· Structural BMP locations
· Drainage delineations and flow information
· Drainage connections
· BMP details
VI.2 ELECTRONIC DATA SUBMITTAL
The minimum requirement is to provide submittal of PDF exhibits in addition to hard copies.
Format must not require specialized software to open.
If the local jurisdiction requires specialized electronic document formats (CAD, GIS) to be
submitted, this section will be used to describe the contents (e.g., layering, nomenclature,
georeferencing, etc.) of these documents so that they may be interpreted efficiently and accurately
Water Quality Management Plan (WQMP)
Pointe Common
Meta Housing Corp. Section III
Preliminary WQMP October 2022 Page 30
Section VII Educational Materials
Refer to the Orange County Stormwater Program (ocwatersheds.com) for a library of materials
available. For the copy submitted to the Permittee, only attach the educational materials specifically
applicable to the project. Other materials specific to the project may be included as well and must
be attached.
Education Materials
Residential Material
(http://www.ocwatersheds.com)
Check If
Applicable
Business Material
(http://www.ocwatersheds.com)
Check If
Applicable
The Ocean Begins at Your Front Door Tips for the Automotive Industry
Tips for Car Wash Fund-raisers Tips for Using Concrete and Mortar
Tips for the Home Mechanic Tips for the Food Service Industry
Homeowners Guide for Sustainable
Water Use Proper Maintenance Practices for Your
Business
Household Tips
Other Material
Check If
Attached Proper Disposal of Household
Hazardous Waste
Recycle at Your Local Used Oil
Collection Center (North County)
Recycle at Your Local Used Oil
Collection Center (Central County)
Recycle at Your Local Used Oil
Collection Center (South County)
Tips for Maintaining a Septic Tank
System
Responsible Pest Control
Sewer Spill
Tips for the Home Improvement Projects
Tips for Horse Care
Tips for Landscaping and Gardening
Tips for Pet Care
Tips for Pool Maintenance
Tips for Residential Pool, Landscape and
Hardscape Drains
Tips for Projects Using Paint
Water Quality Management Plan (WQMP)
Pointe Common
Meta Housing Corp. Section III
Preliminary WQMP October 2022 Page 31
ATTACHMENT A
Water Quality Management Plan (WQMP)
Pointe Common
Meta Housing Corp. Section III
Preliminary WQMP October 2022 Page 32
ATTACHMENT B
ORA
N
G
E
C
O
U
N
T
Y
ORA
N
G
E
C
O
U
N
T
Y
RIVE
R
S
I
D
E
C
O
U
N
T
Y
RIVE
R
S
I
D
E
C
O
U
N
T
Y
ORAN
G
E
C
O
U
N
T
Y
ORAN
G
E
C
O
U
N
T
Y
SAN B
E
R
N
A
R
D
I
N
O
C
O
U
N
T
Y
SAN B
E
R
N
A
R
D
I
N
O
C
O
U
N
T
Y
ORANGE COUNTYORANGE COUNTY
LOS ANGELES COUNTYLOS ANGELES COUNTY
ORA
N
G
E
C
O
U
N
T
Y
ORA
N
G
E
C
O
U
N
T
Y
LOS
A
N
G
E
L
E
S
C
O
U
N
T
Y
LOS
A
N
G
E
L
E
S
C
O
U
N
T
Y
1.05
0.7
10.950.90.850.80.75
0.70.65
0.95
0.7
0.9
0.9
0.75
P:\9
5
2
6
E
\
6
-
G
I
S
\
M
x
d
s
\
R
e
p
o
r
t
s
\
I
n
f
i
l
t
r
a
t
i
o
n
F
e
a
s
a
b
i
l
i
t
y
_
2
0
1
1
0
2
1
5
\
9
5
2
6
E
_
F
i
g
u
r
e
X
V
I
-
1
_
R
a
i
n
f
a
l
l
Z
o
n
e
s
_
2
0
1
1
0
2
1
5
.
m
x
d
FIGURE
JO
B
TIT
L
E
SC
A
L
E
1" =
1
.
8
m
i
l
e
s
DE
S
I
G
N
E
D
DR
A
W
I
N
G
CH
E
C
K
E
D
BMP
04/2
2
/
1
0
DA
T
E
JO
B
N
O
.
952
6
-
E
THTH
ORA
N
G
E
C
O
U
N
T
Y
TEC
H
N
I
C
A
L
G
U
I
D
A
N
C
E
DOC
U
M
E
N
T
OR
A
N
G
E
C
O
.
CA
RAI
N
F
A
L
L
Z
O
N
E
S
SUBJECT TO FURTHER REVISION
0 3.6 7.21.8
Miles
0 6 123
Kilometers
LEGEND
Orange County Precipitation Stations
24 Hour, 85th Percentile Rainfall (Inches)
24 Hour, 85th Percentile Rainfall (Inches) - Extrapolated
City Boundaries
Rainfall Zones
Design Capture Storm Depth (inches)
0.65"
0.7
0.75
0.80
0.85
0.90
0.95
1.00
1.10"
Note: Events defined as 24-hour periods (calendar days) with greater
than 0.1 inches of rainfall.
For areas outside of available data coverage, professional judgment
shall be applied.
XVI-1
PROJECT SITE
ORA
N
G
E
C
O
U
N
T
Y
ORA
N
G
E
C
O
U
N
T
Y
RIVE
R
S
I
D
E
C
O
U
N
T
Y
RIVE
R
S
I
D
E
C
O
U
N
T
Y
ORAN
G
E
C
O
U
N
T
Y
ORAN
G
E
C
O
U
N
T
Y
SAN B
E
R
N
A
R
D
I
N
O
C
O
U
N
T
Y
SAN B
E
R
N
A
R
D
I
N
O
C
O
U
N
T
Y
ORANGE COUNTYORANGE COUNTYLOS ANGELES COUNTYLOS ANGELES COUNTY
ORA
N
G
E
C
O
U
N
T
Y
ORA
N
G
E
C
O
U
N
T
Y
LOS
A
N
G
E
L
E
S
C
O
U
N
T
Y
LOS
A
N
G
E
L
E
S
C
O
U
N
T
Y
P:\9
5
2
6
E
\
6
-
G
I
S
\
M
x
d
s
\
R
e
p
o
r
t
s
\
I
n
f
i
l
t
r
a
t
i
o
n
F
e
a
s
a
b
i
l
i
t
y
_
2
0
1
1
0
2
1
5
\
9
5
2
6
E
_
F
i
g
u
r
e
X
V
I
-
2
a
_
H
y
d
r
o
S
o
i
l
s
_
2
0
1
1
0
2
1
5
.
m
x
d
FIGURE
XVI-2a
JO
B
TIT
L
E
SC
A
L
E
1" =
1
.
8
m
i
l
e
s
DE
S
I
G
N
E
D
DR
A
W
I
N
G
CH
E
C
K
E
D
BMP
02/0
9
/
1
1
DA
T
E
JO
B
N
O
.
952
6
-
E
THTH
ORA
N
G
E
C
O
U
N
T
Y
INF
I
L
T
R
A
T
I
O
N
S
T
U
D
Y
OR
A
N
G
E
C
O
.
CA
NRC
S
H
Y
D
R
O
L
O
G
I
C
SOI
L
S
G
R
O
U
P
S
SUBJECT TO FURTHER REVISION
Source:
Soils: Natural Resources Conservation Service (NRCS)
Soil Survey - soil_ca678, Orange County & Western Riverside
Date of publication: 2006-02-08
!I
0 3.6 7.21.8
Miles
0 5 102.5
Kilometers
LEGEND
City Boundaries
Hydrologic Soil Groups
A Soils
B Soils
C Soils
D Soils
http://websoilsurvey.nrcs.usda.gov/app/HomePage.htm
PROJECT SITE
ORA
N
G
E
C
O
U
N
T
Y
ORA
N
G
E
C
O
U
N
T
Y
RIVE
R
S
I
D
E
C
O
U
N
T
Y
RIVE
R
S
I
D
E
C
O
U
N
T
Y
ORAN
G
E
C
O
U
N
T
Y
ORAN
G
E
C
O
U
N
T
Y
SAN B
E
R
N
A
R
D
I
N
O
C
O
U
N
T
Y
SAN B
E
R
N
A
R
D
I
N
O
C
O
U
N
T
Y
ORANGE COUNTYORANGE COUNTY
LOS ANGELES COUNTYLOS ANGELES COUNTY
ORA
N
G
E
C
O
U
N
T
Y
ORA
N
G
E
C
O
U
N
T
Y
LOS
A
N
G
E
L
E
S
C
O
U
N
T
Y
LOS
A
N
G
E
L
E
S
C
O
U
N
T
Y
10
10
3 5
10
30
10
30
10
20
10
10
5
50
3
30
30
30
3020
5
10
20
30
50
10
30
20
P:\9
5
2
6
E
\
6
-
G
I
S
\
M
x
d
s
\
R
e
p
o
r
t
s
\
I
n
f
i
l
t
r
a
t
i
o
n
F
e
a
s
a
b
i
l
i
t
y
_
2
0
1
1
0
2
1
5
\
9
5
2
6
E
_
F
i
g
u
r
e
X
V
I
-
2
d
_
D
e
p
t
h
T
o
G
r
o
u
n
d
w
a
t
e
r
O
v
e
r
v
i
e
w
_
2
0
1
1
0
2
1
5
.
m
x
d
FIGURE
XVI-2d
JO
B
TIT
L
E
SC
A
L
E
1" =
1
.
2
5
m
i
l
e
s
DE
S
I
G
N
E
D
DR
A
W
I
N
G
CH
E
C
K
E
D
BMP
02/0
9
/
1
1
DA
T
E
JO
B
N
O
.
952
6
-
E
THTH
ORA
N
G
E
C
O
U
N
T
Y
INF
I
L
T
R
A
T
I
O
N
S
T
U
D
Y
OR
A
N
G
E
C
O
.
CA
NOR
T
H
O
R
A
N
G
E
C
O
U
N
T
Y
MAP
P
E
D
D
E
P
T
H
T
O
F
I
R
S
T
GRO
U
N
D
W
A
T
E
R
SUBJECT TO FURTHER REVISION
Note: Data are not available for South Orange County at this time.
Source:
Sprotte, Fuller and Greenwood, 1980.
California Division of Mines and Geology;
California Geological Survey
!I
0 2.5 51.25
Miles
0 4 82
Kilometers
LEGEND
Depth To First Groundwater Contours
City Boundaries
OCWD Groundwater Basin Protection Boundary
PROJECT SITE
ORA
N
G
E
C
O
U
N
T
Y
ORA
N
G
E
C
O
U
N
T
Y
RIVE
R
S
I
D
E
C
O
U
N
T
Y
RIVE
R
S
I
D
E
C
O
U
N
T
Y
ORAN
G
E
C
O
U
N
T
Y
ORAN
G
E
C
O
U
N
T
Y
SAN B
E
R
N
A
R
D
I
N
O
C
O
U
N
T
Y
SAN B
E
R
N
A
R
D
I
N
O
C
O
U
N
T
Y
ORANGE COUNTYORANGE COUNTY
LOS ANGELES COUNTYLOS ANGELES COUNTY
ORA
N
G
E
C
O
U
N
T
Y
ORA
N
G
E
C
O
U
N
T
Y
LOS
A
N
G
E
L
E
S
C
O
U
N
T
Y
LOS
A
N
G
E
L
E
S
C
O
U
N
T
Y
P:\9
5
2
6
E
\
6
-
G
I
S
\
M
x
d
s
\
R
e
p
o
r
t
s
\
I
n
f
i
l
t
r
a
t
i
o
n
F
e
a
s
a
b
i
l
i
t
y
_
2
0
1
1
0
2
1
5
\
9
5
2
6
E
_
F
i
g
u
r
e
X
V
I
-
2
f
_
N
o
r
t
h
O
C
G
r
o
u
n
d
w
a
t
e
r
P
r
o
t
e
c
t
i
o
n
A
r
e
a
s
S
t
r
e
e
t
M
a
p
_
2
0
1
1
0
2
1
5
.
m
x
d
FIGURE
XVI-2f
JO
B
TIT
L
E
SC
A
L
E
1" =
1
.
2
5
m
i
l
e
s
DE
S
I
G
N
E
D
DR
A
W
I
N
G
CH
E
C
K
E
D
BMP
04/2
2
/
1
0
DA
T
E
JO
B
N
O
.
952
6
-
E
THTH
ORA
N
G
E
C
O
U
N
T
Y
INF
I
L
T
R
A
T
I
O
N
S
T
U
D
Y
OR
A
N
G
E
C
O
.
CA
NOR
T
H
O
R
A
N
G
E
C
O
U
N
T
Y
GRO
U
N
D
W
A
T
E
R
P
R
O
T
E
C
T
I
O
N
ARE
A
S
SUBJECT TO FURTHER REVISION
Note: Individual contamination sites are not plotted.
See State Water Resources Control Board Geotracker database
(http://geotracker.waterboards.ca.gov),
Department of Toxic Substance Control Envirostor database
(http://www.envirostor.dtsc.ca.gov) and other applicable sources
for current listing of active contaminated sites.
Groundwater basin and plume protection boundaries for
South Orange County are not shown on this exhibit
at this time
!I
0 2.5 51.25
Miles
0 4 82
Kilometers
LEGEND
City Boundaries
OCWD Groundwater Basin Protection Boundary
Plume Protection Boundaries
North Basin Groundwater Protection Project
South Basin Groundwater Protection Project
El Toro Marine Base
Tustin Marine Air Base
Approximate Selenium Contamination Area
PROJECT SITE
ORA
N
G
E
C
O
U
N
T
Y
ORA
N
G
E
C
O
U
N
T
Y
RIVE
R
S
I
D
E
C
O
U
N
T
Y
RIVE
R
S
I
D
E
C
O
U
N
T
Y
ORAN
G
E
C
O
U
N
T
Y
ORAN
G
E
C
O
U
N
T
Y
SAN B
E
R
N
A
R
D
I
N
O
C
O
U
N
T
Y
SAN B
E
R
N
A
R
D
I
N
O
C
O
U
N
T
Y
ORANGE COUNTYORANGE COUNTY
LOS ANGELES COUNTYLOS ANGELES COUNTY
ORA
N
G
E
C
O
U
N
T
Y
ORA
N
G
E
C
O
U
N
T
Y
LOS
A
N
G
E
L
E
S
C
O
U
N
T
Y
LOS
A
N
G
E
L
E
S
C
O
U
N
T
Y
P:\9
5
2
6
E
\
6
-
G
I
S
\
M
x
d
s
\
R
e
p
o
r
t
s
\
I
n
f
i
l
t
r
a
t
i
o
n
F
e
a
s
a
b
i
l
i
t
y
_
2
0
1
1
0
2
1
5
\
9
5
2
6
E
_
F
i
g
u
r
e
X
V
I
-
2
g
_
I
n
f
i
l
t
r
a
t
i
o
n
F
i
n
a
l
_
2
0
1
1
0
2
1
5
.
m
x
d
FIGURE
XVI-2g
JO
B
TIT
L
E
SC
A
L
E
1" =
1
.
8
m
i
l
e
s
DE
S
I
G
N
E
D
DR
A
W
I
N
G
CH
E
C
K
E
D
BMP
04/2
2
/
1
0
DA
T
E
JO
B
N
O
.
952
6
-
E
THTH
ORA
N
G
E
C
O
U
N
T
Y
INF
I
L
T
R
A
T
I
O
N
S
T
U
D
Y
OR
A
N
G
E
C
O
.
CA
INF
I
L
T
R
A
T
I
O
N
A
N
A
L
Y
S
I
S
OVE
R
L
A
P
P
I
N
G
C
O
N
S
T
R
A
I
N
T
LOC
A
T
I
O
N
S
SUBJECT TO FURTHER REVISION
Analysis Layers Included: 1. Hydrologic Soil Group D, 2. Landslide
Hazard Zone, 3. Groundwater Protection Areas 4. Approximate
Selinium Area, 5. Depth to Groundwater <= 5'
Note: Screening datasets are not exhaustive. The applicant should
always conduct a review of available site-specific information
relative to infiltration constraints as part of assessing the feasibility of
stormwater infiltration.
Source;
Infiltration Constraint Analysis: PACE/Geosyntec
0 3.6 7.21.8
Miles
0 5 102.5
Kilometers
LEGEND
OCWD Groundwater Basin Protection Boundary
City Boundaries
Infiltration Constraints
1 Constraint
2 Overlapping Constraints
3 Overlapping Constraints
4 Overlapping Constraints
PROJECT SITE
P:\9
5
2
6
E
\
6
-
G
I
S
\
M
x
d
s
\
S
u
c
e
p
t
a
b
i
l
i
t
y
M
a
p
s
_
2
0
1
0
0
5
0
5
\
9
5
2
6
E
_
S
a
n
G
a
b
r
i
e
l
C
o
y
o
t
e
C
r
e
e
k
S
u
s
c
e
p
t
i
b
i
l
i
t
y
_
2
0
1
0
0
4
3
0
.
m
x
d
Anaheim Bay-Huntington Harbor
Watershed
Newport Bay-
Newport Coastal
Streams Watershed
Santa River Watershed
Los Angeles County
Channel in
Retarding Basin
Los AlamitosNaval AirStation
Seal BeachNaval WeaponsStation
FullertonAirport
HillcrestParkReservoir
OrangeCounty
La JollaRechargeBasin KraemerBasin
FullertonReservoir
FullertonReservoirBrea CreekReservior
HumbleReservoir
ValenciaReservoir
FullertonReservoir
MillerRetardingBasin
CypressRetardingBasin
Los AlamitosRetardingBasin
PlacentiaRetardingBasin
RaymondRetardingBasin
GilbertRetardingBasin
CrescentRetardingBasin
Loftus DiversionChannelDesilting Basin
RossmoorRetardingBasin
1
JO
B
TIT
L
E
SC
A
L
E
1" =
8
0
0
0
'
DE
S
I
G
N
E
D
DR
A
W
I
N
G
CH
E
C
K
E
D
BMP 04/3
0
/
1
0
DA
T
E
JO
B
N
O
.
952
6
-
E
THTH
ORA
N
G
E
C
O
U
N
T
Y
WAT
E
R
S
H
E
D
MAS
T
E
R
P
L
A
N
N
I
N
G
OR
A
N
G
E
C
O
.
CA
SUS
C
E
P
T
I
B
I
L
I
T
Y
A
N
A
L
Y
I
S
SAN
G
A
B
R
I
E
L
-
C
O
Y
O
T
E
C
R
E
E
K
!I 0 8,000 16,000
Feet
Susceptibility
Potential Areas of Erosion, Habitat, &
Physical Structure Susceptibility
Channel Type
Earth (Unstable)
Earth (Stabilized)
Stabilized
Tidel Influence
<= Mean High Water Line (4.28')
Water Body
Basin
Lake
Reservoir
Other Lands
Airport/Military
SUSCEPTIBILITY MAP UPATE (FEB 2013)
PROJECT SITE
Water Quality Management Plan (WQMP)
Pointe Common
Meta Housing Corp. Section III
Preliminary WQMP October 2022 Page 33
ATTACHMENT C
(818) 994-8895
www.GeoConceptsInc.com
14428 Hamlin St., Suite 200, Van Nuys, CA 91401 + 22601 Pacific Coast Highway, Suite 235, Malibu, CA 92065
November 7, 2022 Project 22-02182
Meta Housing Corporation
Attn: Destiny Clara
11150 W. Olympic Blvd., Suite 620
Los Angeles, CA 90064
Subject:INFILTRATION TEST REPORT
1600 W. Commonwealth Avenue
Fullerton, California
References:
1) Preliminary Geologic and Soils Engineering report by GeoConcepts, Inc. covering the
subject site, dated August 23, 2022.
Dear Ms. Clara:
Pursuant to your request, presented herein is a summary of the findings from logging and
performing infiltration tests for the proposed subsurface infiltration system. It is our understanding
that the proposed infiltration system will be designed to infiltrate first storm runoff into the ground
as shown on the attached Plot Map. It is our understanding that the proposed infiltration trenches
will be about seven feet below the existing grade. Three test pits were excavated to a depth of
six feet on October 25, 2022. The test pit locations are plotted on the attached Plot Map.
The test pits encountered fill and alluvium to the depth of the test pit logging. Encountered fill had
a thickness of 0.5 feet and consists predominantly of sand with minor gravels. Encountered
alluvium deposits consist predominantly of silty sand to sandy silt with minor clay binder. These
soils are considered relatively homogenous in that no discernible layering, structure, fabric,
texture, or changes in the soil type was encountered that would affect the rate or direction of water
movement.
There is no evidence of near-surface groundwater. Highest historic groundwater onsite obtained
from the State of California Seismic Hazard Zone maps is about 20 feet deep. The subject site is
located within a liquefaction zone on the State of California Seismic Hazard Zones Map of the
Fullerton Quadrangle.
November 17, 2022 Page 2
Project 22-02182
The infiltration testing was performed in the bottom of the test pit utilizing the County Method. The
results of the testing are below.
Test Pit
No.
Measured Infiltration
Rate (in/hour)
Test Material Tested
Depth (ft)
1 1.5 Qal 7
2 6 Qal 7
3 6 Qal 7
This testing was performed using metropolitan water from a garden hose. Therefore, the rates
will vary over time. It is recommended that conventional drainage systems be incorporated into
the design of the project as a backup to ensure proper drainage of the site.
The proposed infiltration trenches shall be located a minimum of ten feet from adjacent private
property lines as well as any existing or proposed structures and shall contain an overflow drain
that conducts the overflow drainage to the street.
The following infiltration design guidelines are considered as minimums:
1. Water infiltration into the ground must be a minimum of 10 feet above the groundwater table.
2. The distance between the infiltration facility and the adjacent private property line shall be a
minimum of 10 feet. Note if any buildings, subterranean walls or deep basements exist on
the adjacent property a greater distance may be required
3. Foundations shall be set back a minimum of 10 feet from the infiltration facility and the bottom
of the footing shall be a minimum of 10 feet from expected zone of saturation.
4. No infiltration facility shall be placed to infiltrate into fill material.
5. The infiltration facility shall be designed to overflow to the street in the event that the drainage
capacity is exceeded or in case of future failure to adequately infiltrate.
Findings
1. Based on the relatively homogeneous nature of the soils infiltration at the subject site has
minimal potential for creating a perched water condition that may adversely affect structures.
2. Infiltration in the area depicted on the Plot Map will not saturate soils supported by
retaining/basement walls.
3. Expansive soils are not present in the area of the proposed infiltration. Based on the
distance between the proposed infiltration area and the structures the structures will not be
adversely affected by the infiltration.
4. The soils encountered in the explorations are not anticipated to be subject to
hydroconsolidation that may adversely affect structures.
November 17, 2022 Page 3
Project 22-02182
5. The soils encountered in the explorations are not anticipated to be subject to ground
settlement due to saturation from infiltration, possibly resulting in distress to structures.
Conclusions
1. The proposed site is considered suitable for stormwater infiltration at or below a depth of seven
feet.
2. The infiltration of stormwater will not result in ground settlement that could adversely affect
structures, either on or adjacent to the site.
3. The infiltration of stormwater will not result in soil saturation that could affect
retaining/basement structures.
Should you have any questions regarding this report, please do not hesitate to contact the
undersigned at your convenience.
Respectfully submitted,
GEOCONCEPTS, INC.
Raffi Dermendjian
Project Engineer
PE C. 88261
RD: 22-02182-2
Enclosures: Location Maps
Test Pit Logs
Plot Map
Distribution: (1) Addressee
November 17, 2022 Page 4
Project 22-02182
LOCATION
Reference: GIS-Net
Project
Address:
1600 W. Commonwealth Ave.
Fullerton, CA
November 17, 2022 Page 5
Project 22-02182
GROUNDWATER LEVEL MAP
Reference: State of California Seismic Hazard Zone Reports: Quadrangle Scale: As Shown
Project
Address:
1600 W. Commonwealth Ave.
Fullerton, CA
November 17, 2022 Page 6
Project 22-02182
SEISMIC HAZARD MAP
Reference: California Geological Survey, Seismic Hazard Map
https://maps.conservation.ca.gov/cgs/DataViewer/index.html
Scale: As Shown
Project
Address:
1600 W. Commonwealth Ave.
Fullerton, CA
November 17, 2022 Page 7
Project 22-02182
November 17, 2022 Page 8
Project 22-02182
November 17, 2022 Page 9
Project 22-02182
(818) 994-8895
www.GeoConceptsInc.com
14428 Hamlin St., Suite 200, Van Nuys, CA 91401 + 22601 Pacific Coast Highway, Suite 235, Malibu, CA 92065
TECHNICAL GUIDANCE DOCUMENT APPENDICES
III-16 December 20, 2013
Worksheet B: Simple Design Capture Volume Sizing Method
Step 1: Determine the design capture storm depth used for calculating volume
1 Enter design capture storm depth from Figure III.1, d (inches) d= inches
2
Enter the effect of provided HSCs, dHSC (inches)
(Worksheet A) dHSC= inches
3
Calculate the remainder of the design capture storm
depth, dremainder (inches) (Line 1 – Line 2) dremainder= inches
Step 2: Calculate the DCV
1 Enter Project area tributary to BMP (s), A (acres) A= acres
2 Enter Project Imperviousness, imp (unitless) imp=
3 Calculate runoff coefficient, C= (0.75 x imp) + 0.15 C=
4
Calculate runoff volume, Vdesign= (C x dremainder x A x 43560 x
(1/12)) Vdesign= cu-ft
Step 3: Design BMPs to ensure full retention of the DCV
Step 3a: Determine design infiltration rate
1
Enter measured infiltration rate, Kobserved
1 (in/hr)
(Appendix VII) Kobserved= In/hr
2
Enter combined safety factor from Worksheet H, Stotal
(unitless) Stotal=
3 Calculate design infiltration rate, Kdesign = Kobserved / Stotal
Kdesign= In/hr
Step 3b: Determine minimum BMP footprint
4 Enter drawdown time, T (max 48 hours) T= Hours
5
Calculate max retention depth that can be drawn down within
the drawdown time (feet), Dmax = Kdesign x T x (1/12) Dmax= feet
6
Calculate minimum area required for BMP (sq-ft), Amin =
Vdesign/ dmax Amin= sq-ft
1Kobserved is the vertical infiltration measured in the field, before applying a factor of safety. If field testing measures a rate that is
different than the vertical infiltration rate (for example, three-dimensional borehole percolation rate), then this rate must be adjusted
by an acceptable method (for example, Porchet method) to yield the field estimate of vertical infiltration rate, K observed. See Appendix
VII.
0.90
0
0.90
2.5
.705
.68
5,543
1.5
2
.75
48
3
1,848
TECHNICAL GUIDANCE DOCUMENT APPENDICES
VII-35 December 20, 2013
Worksheet H: Factor of Safety and Design Infiltration Rate and Worksheet
Factor Category Factor Description
Assigned
Weight (w)
Factor
Value (v)
Product (p)
p = w x v
A Suitability
Assessment
Soil assessment methods 0.25
Predominant soil texture 0.25
Site soil variability 0.25
Depth to groundwater / impervious
layer 0.25
Suitability Assessment Safety Factor, SA = p
B Design
Tributary area size 0.25
Level of pretreatment/ expected
sediment loads 0.25
Redundancy 0.25
Compaction during construction 0.25
Design Safety Factor, SB = p
Combined Safety Factor, STotal= SA x SB
Observed Infiltration Rate, inch/hr, Kobserved
(corrected for test-specific bias)
Design Infiltration Rate, in/hr, KDESIGN = KObserved / STotal
Supporting Data
Briefly describe infiltration test and provide reference to test forms:
Note: The minimum combined adjustment factor shall not be less than 2.0 and the maximum
combined adjustment factor shall not exceed 9.0.
1
2
2
1
2
1
1
1
.25
0.5
0.5
0.25
0.5
.25
.25
.25
1.25
1.50
1.875
1.5
2
Three test pits were excavated to a depth of six
feet on October 25,2022. Infiltration testing was
performed using the County Method in the
bottom of the pits. See attached Geotechnical
report for details.
EAST INFILTRATION TRENCH
TECHNICAL GUIDANCE DOCUMENT APPENDICES
VII-35 December 20, 2013
Worksheet H: Factor of Safety and Design Infiltration Rate and Worksheet
Factor Category Factor Description
Assigned
Weight (w)
Factor
Value (v)
Product (p)
p = w x v
A Suitability
Assessment
Soil assessment methods 0.25
Predominant soil texture 0.25
Site soil variability 0.25
Depth to groundwater / impervious
layer 0.25
Suitability Assessment Safety Factor, SA = p
B Design
Tributary area size 0.25
Level of pretreatment/ expected
sediment loads 0.25
Redundancy 0.25
Compaction during construction 0.25
Design Safety Factor, SB = p
Combined Safety Factor, STotal= SA x SB
Observed Infiltration Rate, inch/hr, Kobserved
(corrected for test-specific bias)
Design Infiltration Rate, in/hr, KDESIGN = KObserved / STotal
Supporting Data
Briefly describe infiltration test and provide reference to test forms:
Note: The minimum combined adjustment factor shall not be less than 2.0 and the maximum
combined adjustment factor shall not exceed 9.0.
1
2
2
1
2
1
1
1
.25
0.5
0.5
0.25
0.5
.25
.25
.25
1.25
1.50
1.875
6
3
Three test pits were excavated to a depth of six
feet on October 25,2022. Infiltration testing was
performed using the County Method in the
bottom of the pits. See attached Geotechnical
report for details.
WEST INFILTRATION TRENCH
TECHNICAL GUIDANCE DOCUMENT APPENDICES
VIII-13 December 20, 2013
Worksheet I: Summary of Groundwater-related Feasibility Criteria
1 Is project large or small? (as defined by Table VIII.2)
circle one Large Small
2 W hat is the tributary area to the BMP? A acres
3 What type of BMP is proposed?
4 What is the infiltrating surface area of the proposed BMP? ABMP sq-ft
5
What land use activities are present in the tributary area (list all)
6 What land use-based risk category is applicable? L M H
7
If M or H, what pretreatment and source isolation BMPs have been considered and are proposed
(describe all):
8
What minimum separation to mounded seasonally high
groundwater applies to the proposed BMP?
See Section VIII.2 (circle one)
5 ft 10 ft
9
Provide rationale for selection of applicable minimum separation to seasonally high mounded
groundwater:
10 What is separation from the infiltrating surface to seasonally
high groundwater? SHGWT ft
11 What is separation from the infiltrating surface to mounded
seasonally high groundwater?
Mounded
SHGWT ft
12
Describe assumptions and methods used for mounding analysis:
13 Is the site within a plume protection boundary (See Figure Y N N/A
1.75
Infiltration Trench
RESIDENTIAL
Infiltration Trench will be used as project BMP, therefore 10 ft Minimum shall be
used. Groundwater was found at 42' BGS. Infiltration will occur 7' BGS, providing a
separation of 35'.
1,350.5
35
32.37
From USGS calculation sheet,
groundwater mounding peaks at 39.37' BGS. Infiltration will occur at 7' BGS,
providing 32.37' of separation from mounding groundwater.
A hydrodynamic separator is proposed to pretreat the stormwater runoff from
the site.
EAST INFILTRATION TRENCH
TECHNICAL GUIDANCE DOCUMENT APPENDICES
VIII-14 December 20, 2013
Worksheet I: Summary of Groundwater-related Feasibility Criteria
VIII.2)?
14 Is the site within a selenium source area or other natural
plume area (See Figure VIII.2)? Y N N/A
15 Is the site within 250 feet of a contaminated site? Y N N/A
16
If site-specific study has been prepared, provide citation and briefly summarize relevant findings:
17 Is the site within 100 feet of a water supply well, spring, septic
system? Y N N/A
18 Is infiltration feasible on the site relative to groundwater-
related criteria? Y N
Provide rationale for feasibility determination:
Note: if a single criterion or group of criteria would render infiltration infeasible, it is not
necessary to evaluate every question in this worksheet.
N/A
Sufficient distance from infiltration depth to groundwater.
TECHNICAL GUIDANCE DOCUMENT APPENDICES
VIII-13 December 20, 2013
Worksheet I: Summary of Groundwater-related Feasibility Criteria
1 Is project large or small? (as defined by Table VIII.2)
circle one Large Small
2 W hat is the tributary area to the BMP? A acres
3 What type of BMP is proposed?
4 What is the infiltrating surface area of the proposed BMP? ABMP sq-ft
5
What land use activities are present in the tributary area (list all)
6 What land use-based risk category is applicable? L M H
7
If M or H, what pretreatment and source isolation BMPs have been considered and are proposed
(describe all):
8
What minimum separation to mounded seasonally high
groundwater applies to the proposed BMP?
See Section VIII.2 (circle one)
5 ft 10 ft
9
Provide rationale for selection of applicable minimum separation to seasonally high mounded
groundwater:
10 What is separation from the infiltrating surface to seasonally
high groundwater? SHGWT ft
11 What is separation from the infiltrating surface to mounded
seasonally high groundwater?
Mounded
SHGWT ft
12
Describe assumptions and methods used for mounding analysis:
13 Is the site within a plume protection boundary (See Figure Y N N/A
0.75
Infiltration Trench
RESIDENTIAL
Infiltration Trench will be used as project BMP, therefore 10 ft Minimum shall be
used. Groundwater was found at 42' BGS. Infiltration will occur 7' BGS, providing a
separation of 35'.
579.5
35
25.07
From USGS calculation sheet,
groundwater mounding peaks at 32.07' BGS. Infiltration will occur at 7' BGS,
providing 25.07' of separation from mounding groundwater.
A hydrodynamic separator is proposed to pretreat the stormwater runoff from
the site.
WEST INFILTRATION TRENCH
TECHNICAL GUIDANCE DOCUMENT APPENDICES
VIII-14 December 20, 2013
Worksheet I: Summary of Groundwater-related Feasibility Criteria
VIII.2)?
14 Is the site within a selenium source area or other natural
plume area (See Figure VIII.2)? Y N N/A
15 Is the site within 250 feet of a contaminated site? Y N N/A
16
If site-specific study has been prepared, provide citation and briefly summarize relevant findings:
17 Is the site within 100 feet of a water supply well, spring, septic
system? Y N N/A
18 Is infiltration feasible on the site relative to groundwater-
related criteria? Y N
Provide rationale for feasibility determination:
Note: if a single criterion or group of criteria would render infiltration infeasible, it is not
necessary to evaluate every question in this worksheet.
N/A
Sufficient distance from infiltration depth to groundwater.
TECHNICAL GUIDANCE DOCUMENT APPENDICES
X-13 December 20, 2013
Table X.8: Minimum Irrigated Area for Potential Partial Capture Feasibility
General Landscape
Type Conservation Design: KL = 0.35 Active Turf Areas: KL = 0.7
Closest ET Station Irvine Santa Ana Laguna Irvine Santa Ana Laguna
Design Capture Storm
Depth, inches
Minimum Required Irrigated Area per Tributary Impervious Acre for
Potential Partial Capture, ac/ac
0.60 0.66 0.68 0.72 0.33 0.34 0.36
0.65 0.72 0.73 0.78 0.36 0.37 0.39
0.70 0.77 0.79 0.84 0.39 0.39 0.42
0.75 0.83 0.84 0.90 0.41 0.42 0.45
0.80 0.88 0.90 0.96 0.44 0.45 0.48
0.85 0.93 0.95 1.02 0.47 0.48 0.51
0.90 0.99 1.01 1.08 0.49 0.51 0.54
0.95 1.04 1.07 1.14 0.52 0.53 0.57
1.00 1.10 1.12 1.20 0.55 0.56 0.60
Worksheet J: Summary of Harvested Water Demand and Feasibility
1 What demands for harvested water exist in the tributary area (check all that apply):
2 Toilet and urinal flushing □
3 Landscape irrigation □
4 Other:_______________________________________________________ □
5 What is the design capture storm depth? (Figure III.1) d inches
6 What is the project size? A ac
7 What is the acreage of impervious area? IA ac
For projects with multiple types of demand ( toilet flushing, indoor demand, and/or other demand)
8 What is the minimum use required for partial capture? (Table
X.6) gpd
9 What is the project estimated wet season total daily use? gpd
10 Is partial capture potentially feasible? (Line 9 > Line 8?)
For projects with only toilet flushing demand
11 What is the minimum TUTIA for partial capture? (Table X.7)
12 What is the project estimated TUTIA?
.90
2.48
1.95
730
110
56
TECHNICAL GUIDANCE DOCUMENT APPENDICES
X-14 December 20, 2013
Worksheet J: Summary of Harvested Water Demand and Feasibility
13 Is partial capture potentially feasible? (Line 12 > Line 11?)
For projects with only irrigation demand
14 What is the minimum irrigation area required based on
conservation landscape design? ( Table X.8) ac
15 What is the proposed project irrigated area? (multiply
conservation landscaping by 1; multiply active turf by 2) ac
16 Is partial capture potentially feasible? (Line 15 > Line 14?)
Provide supporting assumptions and citations for controlling demand calculation:
No partial capture and use being used on site.
No
1.01
.282
No
Water Quality Management Plan (WQMP)
Pointe Common
Meta Housing Corp. Section III
Preliminary WQMP October 2022 Page 34
ATTACHMENT D
N76° 46
'
2
0
"
W
N88° 21' 42"E
N83° 51' 39"E
125.00'
N79° 39' 1
4
"
E
42.64'
389.45'
M
a
r
t
h
a
P
l
EX. PL
EX. PL
0.8%
119.03
FS
120.00
FS
N0° 34' 55"E
2.00'
96.68'
Commonwealth Avenue
N0° 34' 55"E
2.00'
B.N.S.F
.
R
a
i
l
r
o
a
d
R
i
g
h
t
-
o
f
-
W
a
y
[N
0
°
3
4
'
5
5
"
E
]
[2
2
5
.
7
1
'
]
[908.97
]
[616.54']
120.70 TC
120.20 FS
120.32 TC
119.82 FS 1.0%
1.0
%
120.70 TC
120.20 FS
118.90 TC
118.90 FS
119.11
FS
119.22 TC
118.72 FS
119.60 TC
119.10 FS
1.0%
119.11
FS
1.6
%
119.11
FS
119.11
FS
1.8
%
118.72
BW
116.38
FS
(116.33)
BW
EX. R/W
(117.52)TC
(116.89)FL (117.98)TC
(117.36)FL40
'28
.
2
'
8'
118.50
FS
118.54
BW
118.64
BW
(118.87)TC
(118.23)FL
(118.70)TC
(118.07)FL
(118.60)TC
(117.97)FL(118.54)TC
(117.93)FL
(118.38)TC
(117.75)FL
119.36
FS
(119.24)
TC
119.13 FF
119.13 FF
(0.33%)
EX. R/W EX. R/W
PROPOSED
PL
EX. PL
EX. PL
EX. PL
3 2
1
118.42
EG
118.58
TG
118.58
TG
119.27 TC
118.77 FS
119.32
EG 119.68
EG
118.42
TG
119.44 TC
118.94 FS 119.44 TC
118.94 FS
1.0
%
1.0
%
0.8
%
1.0
%
1.0%
118.60
EG
0.5
%
0.5
%
1.0%
118.42
TG
118.60
EG
0.5
%
0.5
%
1.0
%1.8
%
119.46 TC
118.96 FS 120.26 TC
119.76 FS
120.92 TC
120.42 FS
118.20
FS
118.73
FS
118.93
FS
0.5
%
118.63
BW
1.5
%
118.81
FS
118.26
BW
119.11
FS
0.8%
118.70
FS
118.97
FS
1.5
%
4.8
%
117.64
BW
119.03
FS 119.11
FS
1.5
%
118.64
FS
117.19
BW
118.50
FS
118
117
119.11
FS
118.60
FS
R=12'R=12'
3
3 3
(118.26)TC
(117.67)FL118.38
FS
118.90
FS
120.73 TC
120.23 FS
121.11 TC
120.61 FS
6420 WILSHIRE BLVD. #1000
LOS ANGELES, CA 90048
310.926.0248
SHEET NUMBER
N.F.C.
Dec 08, 2022 - 4:06pmPLOT DATE:
PROPERTY LINE
LIMIT OF WORK
CONCRETE PAVING ON GRADE PER DETAIL 3, C2.01.
PLANTER AREA PER LANDSCAPE
ASPHALT CONCRETE PAVING
TREE.REFER TO LANDSCAPE FOR DETAILS
INSTALL DRIVEWAY PER CITY OF FULLERTON STANDARD PLAN 121-2.
W=24', X=3'
INSTALL TYPE A CURB AND GUTTER PER CITY OF FULLERTON STANDARD
PLAN 120.
INSTALL SIDEWALK PER CITY OF FULLERTON STANDARD PLAN 122.
OFFSITE CONSTRUCTION NOTES:
LEGEND:
G
R
A
D
I
N
G
P
L
A
N
C1.30
MA
T
C
H
L
I
N
E
-
S
E
E
B
E
L
O
W
F
O
R
C
O
N
T
I
N
U
A
T
I
O
N
MA
T
C
H
L
I
N
E
-
S
E
E
A
B
O
V
E
F
O
R
C
O
N
T
I
N
U
A
T
I
O
N
CUT:
FILL:
REMOVAL AND RECOMPACTION:
NET (EXPORT):
ESTIMATED EARTHWORK QUANTITIES
300 CUBIC YARDS
100 CUBIC YARDS
7,500 CUBIC YARDS
200 CUBIC YARDS
NOTES:
1.QUANTITIES SHOWN ON HERE ARE FOR PLAN CHECK PURPOSES ONLY.
CONTRACTOR TO GENERATE OWN QUANTITIES FOR BIDDING
PURPOSES.
1
2
3
EAST INFILTRATION TRENCH
WEST INFILTRATION TRENCH