Loading...
HomeMy Public PortalAbout3_AOTC Narrative_Master Plan_SPR Arsenal on the Charles Watertown, MA Project Narrative April 8, 2021 Project Team Summary of Approvals The Principal members of the design and permitting team include: The following approvals are being requested as part of this submission package: Owner: Alexandria Real Estate Equities, Inc • Amendment to Campus Master Plan Special Permit with conceptual Landscape Architect: Sasaki Associates, Inc Site Plan Review, PB-2016-01 Architect: SGA • Amendment to Site Plan Review approval of Phase 1, PB 2016-04 to construct Site D Civil Engineer: Stantec Consulting Services Inc. • Site Plan Review Approval of Phase 2 of the Campus Master Plan all in accordance with §§ 9.03, 9.04 and 9.05 to construct Building 1 & Transportation Engineer: Vanasse and Associates, Inc. Building 2 Dry Utility Engineer: VHB ALEXAN DR IA. PAGE 1 2 •,+ ..- ;�` ,�,' i y ram" r r--,-� � •� •i . _ tc } 7 Watertown Mallir on -re t' Arsenal Yards. M. L ti 11 yj Fes' V Project Site I The Proponent proposes to revitalize the campus which contains approximately 29 acres in total located in Watertown, MA. Arsenal on the Charles I April 8, 2021 PAGE 13 Submission Contents Master Plan: Site D: Approval:Amendment to Campus Master Plan Special Permit with conceptual Approval:Amendment to Site Plan Review approval of Phase 1, PB 2016-04 Site Plan Review, PB-2016-01 1. Chapter 2 1 Site D Project Narrative 1. Chapter 11 Master Plan Project Narrative Approval Summary • Approval Summary Zoning Summary • Existing Conditions Architectural Precedent Images • Proposed Revitalization Summary • • Renderings • Zoning Summary Special Permit Supporting Statement • Transportation and Parking Site Plan Review Statement • Special Permit Supporting Statement AODD Design Guideline Summary • Site Plan Review Statement 2. Appendix 2 1 Site D Supporting Documents 2. Appendix 11 Master Plan Supporting Documents *Developer's Stormwater Summary Conference Summary • LEED Checklist • Neighborhood Meeting 1 & 2 Summary Shadow Studies • Transportation Report Lighting Cutsheets • Stormwater Summary 3. Volume 2 1 Site D Plan Set • Acoustic Report • Civil Drawings • Energy Analysis • Architectural Drawings • Pedestrian Wind Study • Cladding Wind Load Study • Bright Horizons Play Area Exhibit 3. Volume 1 1 Master Plan Plan Set • Civil Drawings • Landscape Drawings • Architectural Drawings 4. Stormwater Report ** * See separate Appendix and Drawing Set packages ** See separate Stormwater Report Submission Contents A L E X A N DRIA. PAGE 14 Building 1: Building 2: Approval:Site Plan Review Approval of Phase 2 of the Campus Master Plan all Approval:Site Plan Review Approval of Phase 2 of the Campus Master Plan all in accordance with §§9.03,9.04 and 9.05 in accordance with §§9.03,9.04 and 9.05 1. Chapter 3 1 Building 1 Project Narrative 1. Chapter 4 1 Building 2 Project Narrative • Approval Summary • Approval Summary • Enlarged Site Plan 0 Enlarged Site Plan • Zoning Summary • Zoning Summary • Architectural Precedent Images • Architectural Precedent Images • Renderings 0 Renderings • Special Permit Supporting Statement • Special Permit Supporting Statement • Site Plan Review Statement 0 Site Plan Review Statement • AODD Design Guideline Summary • AODD Design Guideline Summary 2. Appendix 3 1 Building 1 Supporting Documents * 2. Appendix 4 1 Building 2 Supporting Documents • Stormwater Summary 0 Stormwater Summary • LEED Checklist 0 LEED Checklist • Shadow Studies • Shadow Studies • Lighting Cutsheets 0 Lighting Cutsheets 3. Volume 3 1 Building 1 Plan Set * 3. Volume 4 1 Building 2 Plan Set • Civil Drawings • Civil Drawings • Architectural Drawings • Architectural Drawings Submission Contents Arsenal on the Charles I April 8, 2021 PAGE 15 Chapter Master Plan Project Narrative Supporting Amendment to Campus Master Plan Special Permit with conceptual Site Plan Review, PB-2016-01 x 4 Approval Summary Chapter Contents The Petitioner, Alexandria Real Estate Equities, Inc., requests an • Approval Summary Amendment to the Campus Master Plan Special Permit with Conceptual • Existing Conditions Site Plan Review, PB-2016-01, to allow the Petitioner to continue to • Existing Approved Master Plan & Summary of Revisions revitalize and redevelop this 29+ acre site including redesigned site • Proposed Revitalization Summary improvements and enhancements, 2 new life science R&D buildings • Zoning Summary and increased open space. Narrative information supporting the • Transportation and Parking Amendments to the Campus Master Plan Special Permit with Conceptual • Special Permit Supporting Statement Site Plan Review are located in this chapter. • Site Plan Review Statement The Amendment to the Final Site Plan Review granted for Phase 1, PB- 2016-04, will allow replacing the approved three-story 30,000± sf building along Arsenal Street with a single-story building connected to the West Garage with community focused programming and other site and multi- modal transit enhancements. Narrative information supporting the Amendment to Phase 1 are located in Chapter 2. The requested Final Site Plan Review for Phase 2, will be comprised of Building 1 and Building 2, new four-story office and research laboratory buildings and related site enhancements. Narrative information supporting the Final Site Plan Review Approval for Building 1 and Building 2 are located in Chapters 3 and 3, respectively. Approval Summary ALEXAN DRIA. PAGE 18 if ,ey d p�k6tN"�•'L4,�l'� _ iT 1 1 � I r 1� Project Overview Existing Use and Conditions Alexandria Real Estate Equities, Inc. (ARE) purchased the Arsenal On The Campus, located at 311 Arsenal Street in Watertown, MA, totals The Charles campus (the Campus) from Athena Arsenal, LLC (Athena approximately 29 acres and consists of eleven buildings and two parking Health) in late 2019 and proposes to redevelop it into a collaborative and garages on the south side of Arsenal Street in the southeastern part of innovative campus including life science, office, retail, and community the Town. uses, as well as publicly accessible open spaces and streetscape improvements. These proposed improvements are within the spirit of the The Campus is bounded by Arsenal Street to the north, North Beacon July 18, 2016 Campus Master Plan Special Permit (Campus Plan) issued to Street to the south, the Arsenal Court condominium complex and the Athena Health. Town of Watertown's Arsenal Park to the east, and the former Veterans of Foreign Wars facility on Arsenal Street and an automobile storage yard on North Beacon Street to the west. The Arsenal Street corridor is made up of predominantly commercial uses. The existing Campus buildings are surrounded by surface parking lots and vehicular circulation. There are two existing primary open spaces on the campus. A formal green exists along Arsenal Street north of Building 312 and a more informal green faces onto North Beacon Street, west of the existing east garage and south of building 311. A private playground associated with Bright Horizons is located in the green space west of the 400 Talcott Building, which houses the Bright Horizons on the Charles indoor daycare facility. ALEXAN DRIA. PAGE 110 •,+ ..- ;�` ,�,' i y ram" r r--,-� � � •� •i . _ tc } 7 Watertown Mallir on -re t' Arsenal Yards. Fes t V Project Site Context Arsenal on the Charles I April 8, 2021 PAGE I11 � �Id • _ 311 313 Parking ' 97 t • . � I 60 a 131 117 • •R as � r � ��' `2f o r A h� � t. I� "CO 7 Watertown-Cambridge Greenway 1 "+ "Arsenal Streetr r Jf 3 oleAvenu.. z`r aar t V J 11 Y e +?a�ar 11lMp r 1 .. w ' 3 �; •ep" '�•. "fir.. i �F..;h. f. ' �� ,,A , � v , v ,,; W „ , .r Apr arty- •�_„�. •��q i.. �` r� Q c, t o-, Od NO t wl North B L Y !'� ( 1111F1111-der•., 4e6 i Summary of Changes Implemented Since Approved Master Plan A P 1, West Garage constructed r* 2. Park constructed south of the West Garage 3. Bike Path Constructed ..—... Limit of Work - " .0 a Property Line \ A 'c Existing Conditions in 2020 Arsenal on the Charles I April 8, 2021 PAGE 113 I n- �Yt hA5FNA� F mac. LiI�It o. Work i poddng F 313 _ 39 east * 8 7 garage 6 ! i"-• 31 I �� Ora 5 Oft" ® Proposed Building Program Revisions 1. Smaller building proposd in this location w/different use and design * 6 2. Proposed location of new building 1 3. Proposed location of building 1 loading area 4. Proposed building 2 remains in this location,but with a different design �� 6 5. Proposed building 2 loading area ` 6. Buildings removed and GSF reallocated to proposed new buildings 7. Infill connector buildings proposed(Separate amendment application) /: 8. Proposed canopy removed from project 0 Proposed Open Space Revisions 1. Landscape to remain largely as existing/proposed 2. Road alignment to remain with different streetscape design = + ` 3. New roadway alignment proposed 4. Proposed relocation of Bright Horizons play area 5. New landscape design proposed Y 6. Current proposal maintains entry only at Kingsbury versus the 2-way . traffic approved in master plan "1E 49 Approved Master Plan & Summary of 2021 Proposed Revisions ALEXANDRIA. PAGE114 ter: u., r ' PEI W GE TGARA - T r w„� R°iM i= •i �x y, eke, !d yr �,°a ""Ui �'" ^yp-y ;' w':?_M` c.' ENTRANCE .�,:- SI I E D �` -C� ;J- -I Y+'• 'T x e ''•—� (FORMERLY BUILDING 2) N. ARSENALSTREE7 r E ' E -� - Mrimit of Work R-KINGSBURYENTRANCE a :<311 ARSENAL TALCOTT - _ RANCE > WESTGARAGE ARSENAL71 pBq F GREEN 343 ARSENAL �k"" IN." =` wOOLEYAVE OLEYA 9AA� 300 N.BEACON r aza �\�/% ' 100TALCOTT j GARDENS - 312 ARSENAL •i-D�® COMMUNITY - + PARK /,9 ._.;.. ARRIVAL NgE CON REr�y fir:, #LnwN LAWN Y o ? +�A AEVENT C T ET EAST GARAGE 4 1 . r 00 N.BEACON n: RTH 200 TALCOTT BEACONS ... ENTRANCE r —- �O - A I f -; f ;�F��,•�'t KING BLDG 1 BLDG 2 KINGSBURY s' ...jkAbn e ■, o) a D \ �� 400TALCOTT d- "3 tl �)e • z 2KINGSBURY ` 1 I ..��..`` F., I '� 3 KINGSBURY - el 7 COMMA S MANSION. GARDEN HORIZONS "` .�® ``*e �•: I �,.e^'14 r= C c,. to ^� P r.A _`�f, �y PLAYG UND >r = l^\ It 041- f Proposed Campus Master Plan Amendment Arsenal on the Charles I April 8, 2021 PAGE115 Proposed Revitalization Program This document, coupled with the Arsenal Overlay Development District • Repositioning the Campus into a collaborative and innovative campus (AODD) Design Guidelines and the technical plans, outline ARE's vision for including life science, office, retail, and community uses the Campus revitalization. ARE's Campus vision will support the needs of • Relocating proposed new buildings to different locations on the Campus today's life science tenants and accomplish a number of key objectives • Reducing trip generation for the campus including: Reducing surface parking • Increasing area and quality of open space • Expand job opportunities in the life sciences in Watertown • Promote the preservation of the historic resources and character of the property • Allow for density appropriate for economic revitalization Development Summary • Create amenities for the community and visitors including enhanced Building Previously proposed GFA** Building Coverage Floors Use open spaces and improved multi-modal connectivity Approved* (Footprint) Existing Buildings Building 60 19,131 19,131 12,144 2 Office ARE's Proposal Building 97 23,864 23,864 11,591 3 Office ARE proposes to construct two new life science buildings (Buildings 1 Building 118 5,714 5,714 3,169 2 Office Building 118 5,714 5,714 3,169 2 Office and 2 on the attached plans), 2-NW Corner as well as an addition to the West Garage Building 131 56,247 56,247 20,364 4 Office/Day Care (Site D, formerly Building 2, on the attached plans) on Campus as an Building 311 428,794 428,794 147,255 5-South Ridge Office,Fitness Center Building 312 81,614 79,341 31,829 3 Office,Restaurants, Amendment to the PB-2016-01 Campus Master Plan Special Permit Theater Building 37+Addition 48,805 44,202 22,801 2 Office/Lab with Site Plan Review Approval (Master Plan Special Permit), collectively Building 39 128,055 121,123 40,799 5 Office/Lab Building 43 38,650 35,941 21,115 2 Office/Lab referred to herein as the Proposal. Additionally, a small connector and Building 313+Addition 70,692 86,070 42,089 2 Office Lab loading dock addition to 100 and 200 Talcott Avenue are being pursued Total 904,542 903,403 354,237 under a separate minor amendment to the Master Plan Special Permit. Proposed Buildings Previously Approved Buildings 249,558 N/A Together, the proposed new buildings add 227,225 square feet of gross BuildingI N/A 108443 32,357 4 Office Lab floor area (GFA) to the Campus, which is less than what was proposed in Buil ding 2 N/A 111:552 29,434 4 Office Lab the original Master Plan Special Permit. This Proposal differs from the Total N,5 27,22 7,230 1 Amenity space Total 249,558 227,225 69,021 previously approved Master Plan Special Permit in the following ways: GFA Remaining to be Allocated N/A 23,472 Total Campus(No Garages) 1,154,100 1,154,100 423,258 Garages Existing East Garage I I I 54,665 I 6 St. I Pa rkingg 7-N.Beacon Existing West Ga rage 68,611 Parkin 8-Arsenal St. *From 2016 Approved Master Plan Revitalization Program ALEXAN DRIA. PAGE 116 Zoning The Campus is located within the Arsenal Overlay Development District (AODD), and subject to the provisions of the Town of Watertown Zoning Ordinance section 5.12. The Proposal complies with all the dimensional and use requirements of the Zoning Ordinance and the articulated objectives of the AODD Overlay District as outlined in Section 5.12(c). The following zoning chart outlines required zoning criteria and how the Proposal meets those requirements. Zoning Data-Arsenal Overlay Development District Required/Allowed Proposed Status Comments A Use Uses permitted within AODD Uses permitted within AODD Complies B Dwelling Units N/A N/A Complies Dwelling Units not permitted within AODD C Lot Size 10,000 SF 1,281,839 SF(29.4 Ac.) Complies D Minimum Front Yard Setback Arsenal St. Aligned with Building 311 Aligned with Building 311 Complies N.Beacon St.-East of Charles River Rd. 50' 50, Complies N.Beacon St.-West of School St. 25' 88, Complies E Minimum Rear Yard Setback 25' N/A Complies F/G Minimum Side Yard Setback 25' 25' Complies H Maximum Building Lot Coverage 0.5 0.33 Complies I Impervious Coverage N/A 0.67 Complies No requirement for AODD 1 Maximum Building Height Varies Varies Complies See Detailed Height Analyses K Lot Area per Unit N/A N/A Complies Dwelling Units not permitted within AODD L Gross Floor Area See Development Summary See Development Summary Complies See Development Summary M Floor Area Ratio(FAR) See Development Summary See Development Summary Complies See Development Summary N Minimum Open Space 0.15 0.41 Complies O Parking Requirements Automobile 2,761 2,812 Complies See Detailed Parking Analysis 1 Bike Parking/15 Vehicles-185 Bicycle 269 Complies 50%Long Term(92)50%Short Term(93) Zoning Arsenal on the Charles April 8, 2021 PAGE 117 Building Height Analysis Building Height Existing Buildings Building 60 75.1 Building 97 82.7 Building 117 72.4 Building 118 72.4 Building 131 90.9 Building 311 NW Corner 79.5 South Ridge 94.7 Building 312 91.8 Existing East Garage 90.7 Existing West Garage North(Arsenal St) 91.3 South(N.Beacon St) 80.1 Repositioned Buildings Building 37+Addition 91.8 Building 39 87.8 Building 43 93 Building 313+Addition 91.8 Building Proposed Height' Allowed Height Per AODD Status Rationale Zoning Proposed Buildings Building 1 99 102.5 Complies No taller than 24'above the Plane connection Building 311,97 and 60 Building 2 102 104.4 Complies No Taller than 24'above Plane connecting Buildings 312 and 118 Transportation Hub(Site D) 91.3 99.7 Complies No More than 5'taller than South Ridge of Building 311 i Elevation based on 1988 North American Vertical Datum(NAVD 88)-Excludes water tanks,satellite dishes,chimneys,ventilation systems,bulkheads,aerials,church towers or spires, elevator penthouses,solar arrays,and recption antennas per Section 4.10 od the Zoning Ordinance. Building Height Analysis ALEXANDKIA. PAGE 118 LEGEND PROPERTY LINE •• ......••••ZONING EETBAGK RIVER RIVERFRONT AREA IW YEAR FLOODPLAIN WETLAND I,ETLAND HO WILD ZONE IOO'WETLAND EFFER ZONE w ---------150'PET-AND BUFFER ZO1€ - _. .. ALIGNS WITrr - -- __ - PROPOSED _ "'ARSENAL STREET BUILDING 2 ALIGNED Al IA u WILDING 511 I sr BUILDING 311 � � ...... - o ..i . ••...• . PROPOSED WEST _ o o • ................ ..�•• f] �I ....,.. PARKING GARAGE _ r z r T 3 _ e ' 0 PROPOSED OFFICE WOIXEYAVENU E rl I p r BUI ING31 f i ti S ... - zx ••.. • o� BUILDING DIS BUILDING k / �Y___r • BT EXISTING EAST PARKING GARAGE 1 •' `.i _'•rti o _ `....... r . I r r� BUILDING 37 > r r j - r r I V k .I KINGSBURY AVENU PROPOSED =ne - `___ OFFICE ii r� F \ A}11 Y /!j. /'"i%-' _ __- — BUILDING 6O tl T' 11 266' BUILDING 131 1 wx A OFFICE r r mm • O SLUG r..... _ _❑ �o........... \l END 117 • \ PROPOSED •25' IpIp- `•\ OFFCE TAB' ° �° I� �'•� NORTH 1 1 •��f o 1 Approved Site Development Plan Arsenal on the Charles I April 8, 2021 PAGE119 -41 0 .R' -- 25'SIDE SETBACK j AT ARSENAL STREET - r _ _ Z 25'SIDE SETBACK•-----.• --'��_"'�vs• ^ 25'OR 45 DEGREE PLANE NOR T. FROM EDGE OF STREET BEgCONSrREE��r T-- 50'SETBACK EAST OE •••••••• 25'SIDE SETBACK � "T �� py CHARLES RIVER ROAD `, ppp� • �y _... Limit of Work — — Property Line ------ 25'Side Setback T Proposed Master Plan Amendment with Zoning Setbacks ALEXANDRIA. PAGE120 Transportation and Parking A comprehensive Transportation Impact Analysis and Parking Demand The changes to the Campus Plan development program, that was Analysis was performed in support of the original Master Plan Special assessed as a part of the Amended April 2016 Transportation Impact Permit for the Campus. This analysis included a review of traffic Assessment and subsequent related documents that formed the operations and safety at 31 intersections along the Arsenal Street, basis of the July 18, 2016 Campus Master Plan Special Permit, entail North Beacon Street, and School Street corridors under the existing and a shift in the proposed office use to laboratory use. This shift results predicted future conditions. Peak-hour traffic volume increases, resulting in an overall reduction in the amount of commercial space that was from the Campus Plan, were predicted to range from less than 1 percent associated with retail/restaurant uses (-38,616+/- sf), the health/fitness to approximately 4 percent, and the majority of the study intersections center (-37,926+/- sf), and the daycare center (-12,963+/- sf). These were found to be operating under acceptable conditions and would refinements will result in a reduction in the volume of traffic that is continue to operate as such with the implementation of the Campus associated with the Campus Plan of approximately 2,898 vehicle trips Plan and the accompanying roadway, intersection and traffic control on an average weekday (an approximate 16 percent reduction), and improvements. between 145 and 494 vehicle trips during the peak traffic volume periods (a 10 to 37 percent reduction) from the development program that was A comprehensive, multi-modal transportation improvement program was assessed in the Amended April 2016 Transportation Impact Assessment developed to improve traffic flow, enhance safety, and facilitate safe and and subsequent related documents. Accordingly, the elements of the efficient access to the Campus for pedestrians, bicyclists and vehicles. transportation improvement program that were conditioned as a part Some portions of the program have been completed, and some are of the Special Permit and that have been constructed or that are in the currently being advanced. process of being advanced will continue to afford sufficient capacity to accommodate the reduced traffic volumes that will be associated with A central feature of the completed improvements are the connections the modified campus development program. throughout the Campus for pedestrians and bicycles to access the Charles River and its many amenities. The on-going Transportation Demand Management (TDM) program has been successful at reducing the traffic and parking demands of the Campus. Arsenal on the Charles I April 8, 2021 PAGE 121 In furtherance of the multimodal nature of the campus, a transit hub to Transportation Demand Management be serviced by a one-way drive is planned along the Arsenal Street side of the West Garage. This drive will be restricted to shuttle buses (authorized The following Transportation Demand Management (TDM) measures vehicles only), with traffic entering by way of the new traffic signal at have been implemented as a part of the Master Plan Special Permit and the West Garage, and exiting to Arsenal Street by a new driveway that have been successful in reducing the overall number of vehicle trips in the would be regulated (by design and regulatory signs) as right-turn only. area. These measures will continue as a part of the Proposal. The transit hub will allow for the travel route of the campus shuttle to be altered to eliminate the need for it to travel along North Beacon Street. . A full-time, on-site Transportation Coordinator will manage the TDM program Commensurate with the reduction in traffic that will be associated with . Membership to the Watertown TMA the modified campus development program, the overall Campus parking . A privately funded campus shuttle to connect the Campus to area supply will be reduced from 3,167 parking spaces to 2,812 parking public transportation services spaces, or an overall reduction of 355 parking spaces. Zoning requires . Future Tenants leases will require bikeshare membership and that the Campus Plan include a minimum of 2,761 vehicles. Accordingly, transportation benefits for employees. the reduced parking supply will continue to meet the operational . Available information regarding public transportation services requirements of the Campus, while being appropriately balanced to to Campus Tenants and their employees. A "welcome packet" support the TDM program and reduce the potential for off-campus detailing available public transportation services, bicycle and walking parking. alternatives and commuter options available to Campus Tenants and their employees • An Emergency Ride Home (ERH) program available to Campus Tenants and their employees • Pedestrian accommodations that link campus buildings and on-site parking to the sidewalks along Arsenal Street and North Beacon Street • Preferential parking for alternatively fueled vehicles and for car/ vanpools within the Campus parking garages • Electric vehicle (EV) charging stations per the Zoning Ordinance • Shower and lockers rooms will be available to Campus Tenants and their employees • Secure, weather protected bicycle parking and exterior bicycle racks throughout the Campus ALEXAN DRIA. PAGE 122 Parking Requirements Summary Existing Campus This table matches the 2016 MP Land Use Size Units Town Zoning Units Parking Required Per Town Zoning Parking Supply Requirements Office(1st Fir) 245,123 sf 1.0 spaces/350 sf 700 Approved Proposed Office(Other Fir) 483,137 sf 1.0 spaces/400 sf 1,208 East Garage 1,118 1,108 Restaurant 412 seats 1.0 spaces/4 seats 103 West Garage 1,693 1,619 Retail(1st Fir) 0 sf 1.0 spaces/350 sf 0 Surface Parking 132 85 Retail(Other Fir) 0 sf 1.0 spaces/400 sf 0 Tota( 2,943 2,812 Fitness Center 57,926 sf 1.0 spaces/400sf 145 Public Assembly 484 seats 1.0 spaces/5 seats 97 Total Required 2,253 Proposed Change of Uses Town Zoning Change in Parking Required Per Land Use Change in Size Units Units Proposed Short-Term Parking(2-Hour) Requirements Town Zoning Office(1st Fir) -6,999 sf 1.0 spaces/350 sf -20 East Garage(existing) 25 Office(Other Fir) 927 sf 1.0 spaces/400 sf 2 West Garage 0 R&D(Lab-Office) 304,399 sf 1.0 spaces/600 sf 507 Surface Parking 33 Restaurant -75 seats 1.0 spaces/4 seats -19 Total 58 Retail(1st Fir) 0 sf 1.0 spaces/350 sf 0 Retail(Other Fir) 0 sf 1.0 spaces/400 sf 0 Fitness Center -37,926 sf 1.0 spaces/400sf -95 Amenity 31,094 sf 1.0 spaces/375 sf 83 Proposed Accessible Parking (approx.) Public Assembly -45 seats 1.0 spaces/5 seats -9 GFA remaining to be Estimated allocated 23,472 sf 1 0 spaces/400sf 59 Total Proposed Spaces 2,812 Change in Total Required 508 Handicapped Spaces Required(MAAB) 39 Proposed Handicapped Parking Total Existing and New West Garage 12 Land Use Size Units Town Zoning Units Parking Required Per Town Zoning Requirements I I East Garage 22 Office(1st Fir) 238,124 sf 1.0 spaces/350 sf 680 Surface Parking 23 Office(Other Fir) 484,064 sf 1.0 spaces/400 sf 1,210 Total Proposed Handicapped Parking 57 R&D(Lab-Office) 304,399 sf 1.0 spaces/600 sf 507 Restaurant 337 seats 1.0 spaces/4 seats 84 Proposed Electric Vehicle Charging Retail(1st Fir) 0 sf 1 0 spaces/350 sf 0 zoning requirement existing proposed 4 dual chargers Retail(Other Fir) 0 sf spaces/400 sf 0 (charges 8 4 dual chargers 1.0 EV charging stations 5 chargers cars) (charges 8 cars) Fitness Center 20,000 sf 1.0 spaces/400sf 50 Amenity 31,094 sf 1.0 spaces/375 sf 83 (approx.) Public Assembly 439 seats 1.0 spaces/5 seats 88 GFA remaining to be 23,472 sf Estimated spaces/400 sf 59 allocated 1.0 Total Required 2,761 Parking Requirements Summary Arsenal on the Charles I April 8, 2021 PAGE 123 G , J- 77 .rs •:..� ,,.' '; ct.:- .r' J p Q ' ♦fl'511 •.fql .... -E Gara .,. G@5 .R F • - -�'iik- ,M - -_ •- = ; Yz7i Entrance � � I � � �,�: i r _, Arsenal street Building D _ �I ;./ Kingsbury -- , y " Entrance {„__F -_ — C ar 311Arsenal � Talcott - �_ Entrance West Garage •"� �Ae�F t;l AGREEN RSEN L 343Arsenal f - �F�iBhYJ• ( — �Cn, l 300North�1�BH w � d§ 100Talco eacon t � — �LAZA / COMMUNITY _Y f ,.,.# ,�..� T £, ' r LAWN s �'�. r. Talco .. _ PARKy G:`. ;ARRIVAL - O 3 0 Canne o 12 o Fad r5. ` 400 EVENT East Garage ] _ North dP ~ s I P 1 p Beac .- Building - i N.Beacon - 1 200 Talcott i Entrance r . ._ r Buildi ,sng Y p-Off ro I , �,E - F \ ng 2 400 Talcott Arsenal Park '_. ❑ wBright •`€ __. w yE t > k. \` , r Play AreaCommander's_ e 1. � 4 i�,l, - i•• «m r xfc_ •r,_.% - \ `/� Mansion Gardens 'A, Proposed Landscape Plan ALEXANDKIA. PAGE124 Master Plan Special Permit Supporting Statement I Per Section 9.03(C) of the town of Watertown Zoning Ordinance 1. Is the subject site an appropriate location for such use, structure, and/ the surrounding neighborhood during construction. Lastly, the Campus or condition? YES/NO. Explain. Plan is designed to and will be operated to comply with all state noise regulation and local noise ordinances. YES. The Arsenal on the Charles Property is located in the Arsenal Overlay 4. Will adequate and appropriate facilities be provided for the proper Development District (AODD) that specifically contemplated the operation of the proposed use? YES/NO. Explain. Campus Plan and its associated Projects. The Campus development is collaborative and innovative and includes life science, office, retail, YES. and community uses, as well as publicly accessible open spaces and The Campus Plan will be provided with parking, stormwater streetscape improvements that are compatible with existing facilities on management, life-safety and other facilities of high-quality in compliance the Arsenal on the Charles Property. with applicable building and health codes. As noted above, the construction management plan will minimize impacts to the surrounding 2. Will the proposed use/structures adversely affect the neighborhood? neighborhood. YES/NO. Explain. NO. The Campus Plan will improve the neighborhood by creating an attractive new development that will activate the neighborhood and streetscape, enhance safety in the neighborhood, upgrade traffic signals, � .. create new and enhance existing access to bicycle and pedestrian paths, and provide substantial landscape and public amenities. r 3. Is there potential for nuisance or serious hazards to vehicle or pedestrians? YES/NO. Explain. K NO. The Campus Plan will include appropriate and required on-site parking, -with a safe means of ingress and egress, so that the surrounding streets will be unaffected and unobstructed. The Applicant is committed to mitigating adverse traffic impacts created by the Campus Plan through -_ a comprehensive transportation demand management plan. The construction management plan will minimize construction impacts to Arsenal on the Charles April 8, 2021 PAGE 125 Master Plan Special Permit Review Statement I Per Section 9.03(C) of the town of Watertown Zoning Ordinance 1. Landscape 2. Relation of Buildings to Environment The landscape included in the Proposal will be preserved in its natural The architectural expressions of the Proposal's new development state, insofar as practicable, by minimizing tree and soil removal, while celebrate the rich history of the Campus and respect the character of enhancing walkability and pedestrian safety. Minimal grade changes the existing architecture. The materiality and fenestration of the new will insure that the overall landscape will be in keeping with the general buildings draws inspiration from the Campus through the integration of appearance of neighboring developed areas. The proposed revitalization contextual materials and industrial accents. All selected materials will be will preserve and protect the most significant existing trees, while durable, resilient, natural, and sustainable. improving pedestrian routes and internal vehicular circulation. While being respectful of the importance of the principal of preservation, the 3. Open Space Proposal incorporates a range of new gathering spaces and human scale site features throughout the Campus that will help to unify the various The Proposal complies with the Town of Watertown's open space landscape areas into one identifiable and activated environment. The requirements, and also converts several parking areas to landscapes, Proposal also employs a diverse, naturalistic native and adapted plant yielding a net gain of 0.59 acres of usable open space above existing palette that improves both the aesthetic continuity and habitat value of conditions today. the campus. The Proposal will increase and improve the pedestrian experience Adequate landscaping will be provided throughout, including screening throughout the campus, providing an inviting environment that of service and loading areas and utility appurtenances, screening of encourages safe outdoor social interaction. Open spaces are flexibly adjacent residential areas, and provision of new planted buffer strips and designed to accommodate movable furniture, which can be configured street trees along the curbs of internal campus streets. The Proposal ties for social distancing when required. The Campus open spaces will be into the Olmsted historic landscape at the east portion of the property permeable community space, maximizing visibility of destination open along Talcott Avenue and the Commander's Mansion and Arsenal Park spaces and encouraging active use by the public. open spaces east of the Campus on the abutting Town of Watertown properties. Additionally, the Proposal maintains and enhances the The Proposal includes significant upgrades to the interior streetscapes character of the landscape bluff to the South and the monumental iron including new sidewalks, lighting, landscaping, signage and paving. A fencing that borders the majority of the campus. "shared street" concept is proposed for key areas of the Campus that will facilitate a safe pedestrian-oriented environment that also safely The Proposal also includes a long-term comprehensive stormwater accommodates bicycles and vehicles. management strategy for the campus that incorporates several low impact development techniques. ALEXAN DRIA. PAGE 126 r- �'`�or r l TREE REMOVAL ANALYSIS QTY. -- EXISTING TREES WITHIN LOW 442 IEXISTING TREES WITHIN LOW TO REMAIN 180 EXISTING TREES WITHIN LOW TO BE REMOVED >8"DBH 97 <8"DBH 163 / IEXISTING TREES TO BE TRANSPLANTED 2 IPROPOSED TREES 316 - �_ �' -• °- _ j � NET CHANGE IN kOF TREES +75 - IBLOC 311 PARKING GARAGE __ --- BLDG 43 J i �17y VIP rjl v " oU�Ev avEHUE o �.1 BLDG 39 — - - - J k, BLDG 313 =BLDG312 ALCOTT NNE CT O e`en �� •1;1 Z; BLDG 97 IJ ems - V PROPOSEf}� - aLon BLDG 1 PARKING GARAGE - BLDG I] � e Baia r s _ PROPOSED BLDG 2 - - - BLDG 60 BLDG ' -DG 131 D - a :x TSTUDY LEGEND TION eACRIP ow�x� ,a\ \ � ❑ �. I,� \I ,\ i p - •�• w� � � �-''li' .- �\�©ram,—L- ...:`� i •� o am„c�EEro� " t 5 Proposed Tree Preservation and Removal Plan Arsenal on the Charles I April 8, 2021 PAGE127 a a West Garage " Watertown-Cambridge Greenway Entrance I� I Arsenal Street Kingsbury ' Entrance I I I 311 Arsenal Talcott West Garage Entrance I 1/I Ilk Woole Avenue 300 North � I Beacon ' 100 Talcott I L v 312 Q' w Nort r eaco East Garage a North Beacon Street N.Beac Y 200 Talcott o Entrance � 1 Kingsbury L `\ 400 Talcott `\ Arsenal Park Commander's Total site area = 1,281,700 SF (29.42 Acres) Mansion Gardens Total existing open space=504,412 SF (11.58 acres) \ �" N 0 150 300 ft Existing Open Space A L E X A N DRIA. PAGE 128 s ° West Garage " Watertown-Cambridge Greenway Entrance .. Multi-Modal" '--_ Hub � - _ _ Commun - .. Link It - - Kingsbury rEntrance 311 Arsenal _ •• ..1'• 1 7Arse:nal Talcott E�traoce West Garage ' ARSENAL 34 , GREEN , I _ 300 North Drop-Off __ _ -- --- . Beacon _ --� 100 Talcott ' CONITY PPPAAARRR r- Talcott K ARRIVAL = Connect ".r '• .,,,r+ _ LAWN > 312 c EVENT —Building m I 1 w 400 r North i Beaco LAWN East Garage c r Beacon Str et - " I e N. eaeo� Entrance ; 0 Kingsbury I a Je Y° Building 2 s0 ` 1 Kingsbury RIVER F GARDENS 400 Talcott I Total site area = 1,281,700 SF (29.42 Acres) ,� Arsenal Park Required open space= 15%of total site area = 192,255 SF (4.41 Acres) Horizons Total proposed open space= 530,151 SF(12.17 Acres) Play Area •� � Commander's Proposed pervious pavers= 65,101 SF (1.49 Acres) Mansion Gardens N Total pervious surface=420,970 SF (9.66 Acres) 0 150 300 ft Proposed Open Space Arsenal on the Charles I April 8, 2021 PAGE129 The tree-framed green north of Building 312 and adjacent to Arsenal Street will be maintained as a flexible tree-lined open space. be managed to provide optimal circulation for times of day. The four main vehicular access points to the Campus will be maintained. The New open space is developed in the center of the Campus surrounding intersection at North Beacon and School Street will be simplified from the 400 North Beacon Building, ranging in program from a new vehicular the current configuration, while maintaining access to the West garage drop-off court, a welcoming new arrival green, an activated event lawn, from North Beacon Street. Access to the East garage is maintained from a plaza with shade structure, and a series of sensory gardens, walking the signalized Talcott Avenue entrance, from Wooley Avenue to the west, paths, and flexible outdoor work or meeting spaces embedded within or from Kingsbury Avenue off of Arsenal Street. Entrances into the East the gardens. A language of organically shaped granite seat walls and garage will be relocated from the north and south facades to the east planters, concrete unit paving, and robust planting unifies the various side of the garage, providing two, two-way access points from Kingsbury new gathering areas located throughout the campus. Avenue. A new, more informal park landscape of lawn, trees and shrubs that Three main arrival courts will be created to orchestrate vehicular pick-up ties into the path that runs along the southern edge of the Campus is and drop-off throughout the heart of the campus, to prioritize pedestrian developed south of building 2. A new drop-off court unifies the entrances circulation, and to service the newly constructed buildings. Below is a of Building 2, 1 Kingsbury, Branchline, and the east garage. description of the proposed primary drop-off areas: 4. Circulation • At the intersection of Wooley Ave and School Street: This drop-off will serve the new Building 1, 311 Arsenal, and 400 North Beacon Street, The Campus circulation system will be enhanced to maximize convenience as well as allow rideshare vehicles to pick-up/drop-off from the south and safety of vehicular, bicycle, and pedestrian movement within the and then exit back out onto North Beacon Street. campus and in relation to adjacent streets and path connections. The • At the south end of the north-south segment of Kingsbury Avenue: Proposal prioritizes the flow and interaction of pedestrians and cyclists This drop-off will serve the new Building#2, 1 Kingsbury, and retail over motorized vehicles within the Campus. Special attention has been located in the south end of building 312, as well as allow rideshare given to infrastructure and design that will enhance public transit. pick-up/drop-offs to exit back out onto the Talcott Street entrance. • At Arsenal Street near the west garage addition to serve the Wooley Avenue, Kingsbury Avenue and Talcott Avenue will be developed multimodal hub at the Site D building. This drop-off will be for shuttles as "shared streets" to enhance the pedestrian experience while providing only, but otherwise will be closed to personal or rideshare vehicles. access to parking and drop-off zones on Campus. These shared streets will be two-way or one-way as noted on the following diagram, and will ALEXAN DRIA. PAGE 130 A pull off lane on Kingsbury Avenue along the east facade of 311 Arsenal The on-site circulation will create an inclusive and accessible Street also serves as a stop for the campus shuttle. A drop-off/valet area environment. Internal circulation will be ADA/MAAB compliant. is also provided east of the Mosesian Center on Thornton Avenue. Parking for the existing retail component of the project will be provided The proposed building uses reduce overall parking demand, allowing for primarily in the East parking garage, including 25 dedicated short- the reduction of parking from the previously approved plan and enabling term spaces in the lower level, and 33 short-term surface parking are the creation of a more pedestrian friendly, green campus. ADA and also available to visitors along Kingsbury Avenue, Talcott Avenue, and short term parking is retained close to public amenities, such as Panera, Thornton Avenue. Special event parking and non-peak hour parking will Branchline and the Mosesian Theater. Structured parking is located in the also be available in the East garage for visitors to the campus. East and West Garages. The proposed plan reduces surface parking from 138 spaces to 85. Structured parking is reduced from 3,167 to 2,727, and Emergency access to the site will be provided utilizing the existing street is accommodated in the existing east and west garages - the previously network, the shared streets, and the multi-use trail at the west side of the planned third garage is no longer required due to reduced parking west garage. An emergency access route will also be provided to the west demand. Electric vehicle charging stations are provided in the garages per of the 2 and 3 Kingsbury Avenue buildings via an expanded pedestrian the Zoning Ordinance. pathway. The Campus Plan meets the requirements for off-street loading. Minor modifications to the bicycle and pedestrian paths along the western edge of the site are proposed to improve the connection to North Beacon Street. Bicycle access through the site will benefit from the shared street concept as well as enhanced internal bike paths and access points. There will be significant covered and uncovered bicycle storage facilities located throughout the site. The current plan proposes 269 bicycle parking spaces, 92 of which will be long-term (private) parking, secure and protected from the elements, and 177 will be short-term (public or visitor) parking, visible and convenient to building entrances. Arsenal on the Charles April 8, 2021 PAGE 131 West Garage Entrance � � Right-out Multi-Modal I. - Limit of Work Hub • • Kingsbury •• i • ., �Entra nce •� �� Arsenal Street -a— I♦ Community • _ d'••• Talcott • t Link � Entrance I� 311Arsenal _yy}x*,>E: .a� T _J West Garage : ARSENAL' •• • ..� �' GREEN 343 Arseral I • i N.Beacon - • i 300 I North rop-Off Beacon GARDENS 100Talcott �• • PLAZA 1 �f �• i i T81C0$ r" • Co PARK I� • ARRIVAL I� a nnei d^ I • LAWN v 312 rrr • > o 400 North EVENT s • Beacon LAWN Building East Garage ••• r � 1 Y 200 Talcott N.Beacon •` ) , Entrance •• _ ■ Kingsbury Building 2 •• � Drop-Off I ■ 1 Kingsbury RIVER , ` 4 GARDENS 0 Talc Charles River ` r -- -- - J Arsenal Park Bright I Two-way Shared Road(Bicycle/Vehicular) Horizons V Talcott Avenue gated to —� One-wayShared Road Bic cle Vehicular 'lay Ar.aJ thesouth-noaccessto ( Y / ) Greenough Blvd or North Two-wayRoad Vehicular Commander's Beacon street (Vehicular) �• Mansion Gardens ------ Service/Loading Service/Loading Point N --- --- Limited Vehicular Access(Emergency/Service) • © Existing Signalized Intersection Commander's Mansion 0 rN 150 300 ft Proposed Vehicular Circulation A L E X A N DRIA. PAGE 132 o y Watertown Cambridge Greenway West Gara Entran Multi-Modal - - - Hub / Entrance 311Arsenal IWest Garage — I ARSENAL 343ArsenalN.Bea Entrance WooleY Avenue ��_ J J ' � ' --- on Drop- 300 North Drop-Off Beacon GARDENS 100 Talcott PLAZA COMMUNITY a tt I ARRIVAL - � C n nenect LAWN 312 a I N.Beacon 4 North' L.VAUVN EastGara e _ -- Nor �� Entrance eato/J� Building g North Beacon Street - / 1 4 I . 200 Talcott . Drop-Off t _ Drop-Off I _j 0,et °a Building 1 Kingsbury r� g 2 I RIVER ffQLT..Ic� GARDENS aMBTA Bus Route 70/70A _ _ .. J Arsenal Park L� r OMBTA Bus Stop 70/70A o` at.. Bright +•� Horizons I Play Area Shuttle Route Commander's Mansion Gardens lO Shuttle Stop .` �' © Existing Signalized Intersection ' 0 150 300ft Proposed Transit Arsenal on the Charles I April 8, 2021 PAGE 133 h 0 West Garage r° Entrance Watertown-Cambridge Greenway Qmulti-Modal � "b° '- _ Limit of Work Arsenal Street Kingsbury ------ '_� ,� Entrance Talcott - _ Entrance 313Arsenal d'• 1-• �x'-� .. Q.,t.. ARSENAL 343 Arsenal 1 GR EEN - W001ey Avenue ' I/J 300 North Drop-Off '111 Beacon GAR)NS 200 Talcott PLAZA COMMUNITY alco t PARK ARRIVAL ' C nnect r �„f •,-..t_� LAWN -S 312 - ` -._• Nort EVENT c 0 North•? �-. eaco LAWN G o eaco°Street ---- v �~ 200 Teleott Entrance � �• e eo Kingsbury Dr—op-Off Building 2 ,` 1 Kingsbury .. I a U RIVER Charles River L GARDENS 400 Talcott a , r Arsenal Park Bright Parking Spaces Zoning Approved Proposed Horizons I Requirement Play Area Surface N/A 138 85 +� Commander's Surface Parking Mansion Gardens _ Garage Parking Garage N/A 3,029 2,727 ` N Total 2,683 3,167 2,812 ` 0 150 300 ft Proposed Parking Plan A L E X A N DRIA. PAGE 134 h o c t ;© Watertown-Cambridge Greenway I �© Limit of Work i • � Arsenal Street Community / Link 311 Arsenal © ■ ^r i I I West Garage ARSENAL GREEN + 343Ar5enal y✓oole Avenue -- - --—_ r i 300 North Drop-Off GA NS r ~� , PLA • _ Beacon --- ��■ 100 Talcott � COMMUNITY w I Talm PARK f • ARRIVAL v Co mec r LAWN ¢' 312 •♦� / ' ` ' ♦ 400 NOrt LAWN East Garage °EVENT �� ; ♦ Beacon Building m 1 Y ♦♦Q: 200Talcott , � I •• _ -_ Kingsbury • Drop-Off ' I I Building 2 1 Kingsbury RIVER Charles River GARDEN �40 Tdlcott 9 I Arsenal Park Bright Horizons ' Play Area ------- Crosswalk ` J Commander's Mansion Gardens Sidewalk ` N Primary Pedestrian Path(Off-street) '•` �• Secondary Pedestrian Path(Off-street) © Existing Traffic Signal V• 0 150 300 ft Proposed Pedestrian Circulation Arsenal on the Charles I April 8, 2021 PAGE 135 0 Watertown-Cambridge Greenway _Wulti-Modal / 1Rib� Bike Storage and _ Repair Facility Community - "" . •• I Link Z , • •-_e- 311 Arsenal 1 - I West Garage _ ARSENA 343 Arsenal Improved Bike �� Woo GREEN connection to North ey Avenue Beacon Street(cross at N.Beacon I _ i I Paul Street intersection 300 North Drop-Off _ - to the west) - Beacon - - 100 Talcott ; PLAZA GARDENS Talcott COMMUNITY ARRIVAL > > nnect r t PARK LAWN v 312 a ' • 400 North EVENT g 5 • Beacon LAWN East Garage s Building °O ' 1 Y I I 200 Talcott N.Beacon ` ,• J Entrance -- - _ E - "' Building 2 1 Kingsbury � RI 400 T I oca tt I Charles River GARDENS Arsenal Park r - Two-way Shared Road(Bicycle/Vehicular) ..r. ;:;rE+ •�` Bright Horizons I One-way Shared Road(Bicycle/Vehicular) Play Area Off-Street Shared Path(Bicycle/Pedestrian) •� Commander's Dedicated Bike Lane Mansion Gardens Off-Street Multi-Use Trail(Bicycle/Pedestrian) ♦•` N Bike Dismount Zone /• © Existing Signalized Intersection --�• 0 150 300 ft Proposed Bicycle Circulation A L E X A N DRIA. PAGE 136 a 0 16 Watertown-Cambridge Greenway f -' ' . "°I"-"'I°ha'" Hub Limit of Work .' Proposed 19-Bike Community -. .r Blue Bike Station I Link �, . 331Arsenal Z. mj m�� -•_�,y J I West Garage -�. ARSENAL 343 Arsenal GREEN � Wooley gvenue -- _ • N.Beacon I300 North Drop-Off W Beacon GARDENS 100Talcott COMMUNITY —' PLAZA I PARK alcott C nnect 312 -- ' ARRIVAL a a I � '• ` - LAWN 400North/ EVENT LAWNo • _ Beacon 7) East�Garage omBuilding Y I • � f � � � m 200 Talcott Kingsbury — -----.. �•` Drop-Off m Building 2 ♦ ` 1 Kingsbury m I ♦♦ _ RIVER -......_.. ` GARDENS 40 Talc , I _ Arsenal Park Bike Storage Required by Existing Approved Proposed Bright Q Existing Public Bike Storage Zoning •� Horizons I 0 Proposed Public Bike Storage Long-Term Covered 92 0 143 92 Play Area (Private) Commander's 93 177 100 177 E] Proposed Private Bike Storage Short-Term Mansion Gardens 0 (Public)Proposed Bike Share Location ♦� rf N Total 185 177 243 269 �'` . 0 150 300 ft Proposed Bicycle Parking Arsenal on the Charles I April 8, 2021 PAGE 137 5. Surface Water Drainage • Permeable pavements (Stormwater Management) • Rainwater harvesting • Water quality swales TThe Proposal includes a comprehensive and integrated stormwater • Rain gardens/ Bio-retention systems management plan to enhance the previous campus improvements. One • Tree box filters and soil cells of the Campus Plan design goals is to create a stormwater system that is • Subsurface detention integrated into the landscape and visible to users of the campus where • Subsurface infiltration possible. Walking through the campus you will encounter rain gardens along Kingsbury Avenue, as well as permeable pavements along shared Where practicable, Stormwater will be collected from roofs and paved streets lined with trees planted within bio-retention systems. Native and areas and directed to subsurface detention or detention/infiltration drought tolerant landscape materials are proposed to minimize irrigation. systems, which will, to the extent required, overflow to the municipal drainage system. Those systems will retain stormwater from typical The proposed stormwater management system is designed to meet and frequent storm events and retain and detain stormwater from the Massachusetts Department of Environmental Protection's (DEP's) larger storm events resulting in a significant reduction in the flow rate Stormwater Management Standards. With respect to the recharge and volume of stormwater discharged from the site. Rain gardens, bio- requirements of Chapter 98: Stormwater Management and Erosion retention systems and tree box filters all contribute to a comprehensive Control of the Town of Watertown's Code of Ordinances and the treatment train improving water quality. Full details of the comprehensive corresponding Rules and Regulations, the proposed stormwater stormwater management strategy are described in the Stormwater management system has been designed to the best extent practicable. Report. Off-site mitigation, including drainage improvements at the Commander's Mansion and within Talcott Avenue, has been reviewed and coordinated See Volume 1 of the Plan Set Documents for the overall Stomwater and with the Town. The system has been designed to be implemented in documents phases as individual building sites are developed on the Campus. The overall stormwater management strategy is designed to reduce the rate and volume of stormwater flow discharging from the campus site, including provisions for groundwater recharge and significant water quality improvements. The goals of the overall strategy will be achieved through implementation of a multi-faceted approach that includes Best Management Practices (BMP's) and Low Impact Design (LID) techniques which include: ALEXAN DRIA. PAGE 138 .� ­�' * - "firms . .E e r t Y __0 * ARSENAL S . - `^ Aft i /V C)R7h,3 .. . r 3o , z .i • y+ � l f + Percent Reduction of Peak Flow Rate Stormwater 2-Year 10-Year 25-Year 100-Year d Bio-Retention Area Design Point Storm(3.2") Storm(4-9") Storm(6.2") Storm(8.9") 1 19.3% 22.4% 23.6% 20.4% 2 39.8% 31.0% 24.9% 8.5% Subsurface Stormwater System 3 17.6% 11.3% 10.0% 8.6% 4 95.3% 81.5% 75.1% 73.3% ® Stormwater Design Point S 0.0% o-ago 0-0go 0-0% 7 6 100-0°k 100-004 100-001> 100-15% 7 83.39E 66.29E 49.79E 37.8% Proposed Stormwater Plan Arsenal on the Charles I April 8, 2021 PAGE139 6. Utility Service 7. Environmental Sustainability Full utility service is provided throughout the Campus. All electric, ARE is committed to developing and operating efficient and healthy telephone, cable TV and other communication distribution and service buildings, reducing carbon pollution, and managing climate risk. The infrastructure will remain underground on the Campus. An overall following sustainability strategies are being implemented on the Campus: Campus evaluation of underground utilities is underway to locate, Buildings 1 and 2 will demonstrate compliance with the Section 7 document and assess condition to inform life-cycle analysis and inform Environmental Sustainability criteria and the LEED Gold Certified future construction projects. As individual building sites are developed, requirement using the LEED version 4 Core and Shell rating system. At electric and communication duct banks, conduits, wires and cables will be this time, Building 1 is tracking 64 points as "Yes" with an additional further evaluated and relocated, repaired or replaced as required. 10 "Likely" points, therefore exceeding the required 60-point Gold threshold. Building 2 is tracking 65 points as "Yes" with an additional Water and sanitary sewer distribution mains and related water/sewer 6"Maybe" points, therefore exceeding the required 60-point Gold utility services will be replaced at key locations throughout the campus threshold. as the site is revitalized. New water distribution infrastructure, including Site D will demonstrate compliance with the Section 7 Environmental mains and valving is designed to improve system flow and control to the Sustainability criteria and the LEED Gold Certified requirement using campus facilities. Sanitary sewer flow from the proposed Building 1 and the LEED version 4/4.1 New Construction Rating System. At this Building 2 sites will be directed to the North Beacon Street collection time, the project is tracking 70 points as "Yes" with an additional system. Sewer flow from the proposed Site D Building (West Parking 10 "Maybe" points, therefore exceeding the required 60-point Gold Garage addition) site will be directed to the Arsenal Street collection threshold. Additionally, Site D will demonstrate compliance with Net system. Based on a review of the existing conditions survey, our estimates Zero Energy building standards and will seek certification from the of the expected capacity of the existing municipal sewer system in North International Living Future Institute (ILFI), US Green Building Council Beacon Street and Arsenal Street, and of the existing and projected (USGBC), or an equivalent organization. sewage flows from the Campus Enhancement Plan site, the existing sewer • The project team is working collaboratively with a consultant to plan collection systems have sufficient capacity to convey sewerage generated photovoltaic arrays on the east and west garage roofs. from the Arsenal site from the existing and proposed conditions. • Occupancy sensors and lighting controls will be implemented at the upper levels of the West Garage • Lighting (LED) upgrades will be implemented in common building areas and new LED lighting will be implemented in exterior open spaces ALEXAN DRIA. PAGE 140 • Free electric vehicle charging stations and preferential parking for low 9. Safety emission, fuel efficient vehicles will be provided in the existing East and West Parking Garages The Proposal enhances the safety and security of the public, guests, • Enhanced connections to existing bicycle infrastructure and pathways visitors and employees. The Campus is accessible by emergency vehicles are provided, as well as a new 19-bike Blue Bike share station from Arsenal Street via Kingsbury and Talcott Avenues as well as from • Additional covered storage for bikes, as well as bike repair resources North Beacon Street via School Street. Site D is accessible from Arsenal will be provided Street via the West Garage entrance driveway and shuttle drop-off lane • LID stormwater management strategies will be integrated into the that runs parallel to the north facade of the garage. landscape throughout the campus, including pervious pavers at pedestrian plazas, and bioretention areas and rain gardens where In addition, the Proposal includes new LED outdoor lighting to enhance needed to meet water quality requirements safety. Security cameras will be installed around the property. In addition, • Native and adapted plant species will be planted in new landscapes to a state-of-the-art access control system will provide secure access to the improve habitat value and reduce irrigation demand buildings. • Single stream recycling will be employed 8. Screening The Proposal includes screening strategies to reduce visibility of equipment and infrastructure from adjacent neighborhoods. Rooftop equipment and enclosed penthouses at Buildings 1 and 2 are shielded from view by architectural screen walls. Screen colors and finishes will be designed to complement the aesthetic and material language of the buildings. Ground mounted-equipment will be screened through a combination of screen walls and tree and shrub planting. Loading docks at Buildings 1 and 2 will be depressed into the landscape and will be shielded from view with both screen walls and vegetated buffers. Arsenal on the Charles April 8, 2021 PAGE 141 10. Design The Proposal is informed by the formal design review completed pursuant to Section 9.03(d) and is consistent with the standards identified in the Watertown Design Guidelines and Arsenal Overlay Development District (AODD), including the building scale, massing, setbacks, architectural expression and landscape design. In addition, the Proposal meets all aspects of the siting and design guidelines of section 5.12.g of the Zoning Ordinance. The three new buildings have been designed to enhance and blend into the existing campus and community fabric and to be visually appealing. New construction has been designed to be sensitive to character-defining features of the campus, including building and structure exteriors, fenestration, scale, color, use of material, mass, and views to, from, and across the Olmstead-designed landscape. The design will also be consistent with the requirements of the Secretary of the Interior's Standards for Rehabilitation and Guidelines for Rehabilitating Historic Structures. The design was developed to minimize impacts to abutting properties. Measures include complying with all zoning height and setback requirements, breaking down the massing of buildings to reduce overall scale, and integrating rooftop and site screening to minimize visibility, noise, odor, heat vibration and dust impacts of utility equipment and loading areas. Design of the stormwater system improves the existing off-site conditions and water quality. The proposed transportation management plan and energy efficient building design minimizes impacts on air quality. Lighting will be designed particularly for parking and pedestrian areas of the campus to use cut-off fixtures to minimize impacts on abutting properties. 10. Construction Phasing _ D �GE CE1 CE6 - aG�xG � I / o 1 CE7 „o.G„ CE8 P BunpxGr CE3 O -- - CE10 CE9 CE4 CE2 CE5 Area Designations _ , Buildinq Sites D = BUILDING D 1 = BUILDING 1 2 = BUILDING 2 �O Campus Enhancements ---- CE1 -Wooley Ave and School St �A CE2- Bright Horizons Playground Relocation — CE3- Kingsbury Ave Relocation CE4-South Campus Courtyard CE5-Commander's Mansion and Talcott Ave CE6-321 Arsenal Lawn and Kingsbury Ave (North of wooley Ave) CE7- Kingsbury Ave(south of wouoey Ave.) CE8-Thornton Ave CE9- 1-3 Kingsbury Ave Courtyard CE10-400 Talcott Turnaround Driveway Phasing Plan Arsenal on the Charles I April 8, 2021 PAGE 143 Construction Phasing June 2021 July 2021 CE1—Woolev Ave. and School St. CE1—Woolev Ave. and School St. 1. Underground Utility Work (Water, Sewer, Stormwater, Gas, Electric, 1. Underground Utility Work (Water, Sewer, Stormwater, Gas, Electric, Telecom) Telecom) 2. Permanent Curbing and Sidewalks (North side of Wooley and West 2. Permanent Curbing and Sidewalks (North side of Wooley and West side of School) side of School) 3. Temp Binder and Topcoat Roads for Future 3. Install Sewer & Stormwater Connections in North Beacon St. 4. Landscape Areas Temp. Seeded for Future 4. Temp Binder and Topcoat Roads for Future 5. Landscape Areas Temp. Seeded for Future CE2 - BriRht Horizons PlavRround Relocation 1. Removal & replacement of soil CE2— BriRht Horizons PlavRround Relocation 2. Installation of new fencing 1. Installation of playground fill and rubber surface 3. Install sidewalks from 400 Talcott Ave to the playground 2. Relocation of existing equipment or the installation of new 3. Repair/Install Surrounding Landscaping CE3 - Kin2sbury Ave Relocation 1. Underground Utility Work (Water, Sewer, Stormwater, Gas, Electric, CE3 - KinRsbury Ave Relocation Telecom) 1. Underground Utility Work (Water, Sewer, Stormwater, Gas, Electric, 2. Installation of Stormwater Infiltration System Telecom) 2. Installation of Stormwater Infiltration System CE4—South Campus Courtvard 1. Underground Utility Work (Sewer, Stormwater) 2. Installation of South Portion of Large Stormwater Infiltration CE5—Commander's Mansion and Talcott Ave. 1. Underground Utility Work (Stormwater) 2. Installation of Stormwater Infiltration in 440 Talcott Parking Lot 3. Installation of Stormwater Infiltration at Corner of Talcott Ave and N. Beacon St. Construction Phasing ALEXAN DR IA. PAGE 144 August 2021 September 2021 1 - Buildiniz 1 1 - Buildiniz 1 1. Establish Perimeter Site Fence at Boundaries of Building Construction 1. Maintain Perimeter Site Fence at Boundaries of Building Construction Site Site-All work contained within the site fence 2. Underground Utility Work (Stormwater) 2. Underground Utility Work (Stormwater) 3. Install Stormwater Detention System 3. Install Stormwater Detention System CE1-Woolev Ave. and School St. CE3 - Kin2sbury Ave Relocation 1. Permanent Curbing and Sidewalks (North side of Wooley and West 1. Permanent Curbing and Sidewalks (North side of street only) side of School) 2. Temp Binder and Topcoat Roads for Future 2. Temp Binder and Topcoat Roads for Future 3. Landscape Areas Temp. Seeded for Future 3. Landscape Areas Temp. Seeded for Future CE4-South Campus Courtvard CE3 - Kin2sbury Ave Relocation 1. Underground Utility Work (Sewer, Stormwater) 1. Underground Utility Work (Water, Sewer, Stormwater, Gas, Electric, 2. Installation of South Portion of Large Stormwater Infiltration Telecom) 3. Repair Existing Sidewalks 2. installation of Stormwater Infiltration System 4. Repair Disturbed Softscape Areas 3. Permanent Curbing and Sidewalks (North side of street only) 4. Temp Binder and Topcoat Roads for Future CE5-Commander's Mansion and Talcott Ave. 5. Landscape Areas Temp. Seeded for Future 1. Underground Utility Work (Stormwater) 2. Installation of Stormwater Infiltration in 440 Talcott Parking Lot CE4-South Campus Courtvard 3. Installation of Stormwater Infiltration at Corner of Talcott Ave and N. 1. Underground Utility Work (Sewer, Stormwater) Beacon St. 2. Installation of South Portion of Large Stormwater Infiltration 4. Permanent Curbing and Sidewalks 3. Repair Existing Sidewalks 5. Install Binder and Finish Topcoat Asphalt 4. Repair Disturbed Softscape Areas 6. Repair Disturbed Softscape Areas CE5-Commander's Mansion and Talcott Ave. 1. Underground Utility Work (Stormwater) 2. Installation of Stormwater Infiltration in 440 Talcott Parking Lot 3. Installation of Stormwater Infiltration at Corner of Talcott Ave and N. Beacon St. Arsenal on the Charles April 8, 2021 PAGE 145 Chapter Site D Project Narrative Supporting Amendment to Site Plan Review approval of Phase 1 tvll y„ b � mom y1 J w. P ^ M ` i ( �I l 1 N Approval Summary Chapter Contents The Petitioner, Alexandria Real Estate Equities, Inc., requests an • Enlarged Site Plan Amendment to the Final Site Plan Review granted for Phase 1, PB-2016- • Zoning Summary 04. This Amendment will allow replacing the approved three-story • Architectural Precedent Images 30,000± sf building along Arsenal Street with a single-story building • Renderings connected to the West Garage with community focused programming • Special Permit Supporting Statement and other site and multi-modal transit enhancements. referred to herein • Site Plan Review Statement as "Site D". Narrative information supporting the Amendment to Phase 1 • AODD Design Guideline Summary are located in this chapter. Site D is a one-story addition to the existing West Garage located at the northwest corner of the Arsenal on the Charles campus. The project includes screening the north and portions of the east and west facades of the existing garage. The project also includes the addition of photovoltaic panels to the roof of the existing garage. The building will be designed to achieve LEED Gold and FitWel certification ALEXAN DR IA. PAGE 148 ARSENAI_STREET f t`� �'�/ �' •! � ! �'�y, ��4��. ,yam M ' "v 's`• ( SHUTTLE DROP OFF '001111111pow— VIP— PUBLICLY ACCESSIBLE BIKE ROOM/ AMENITY REPAIR SHOP - —-- EXISTING PARKING GARAGE I ...� 31 Site Plan Arsenal on the Charles April 8, 2021 PAGE 149 -41 SITE (FORMERLYBUILDING 2) v� ••-••25'SIDE SETBACK t _ r AT ARSENAL STREET - - - ARSENAL STREET �, 25'SIDE SETBACK•-•••••• -- :_,ti 25`0R 45 DEGREE PLANE••--•-•- NORT FROM EDGE OF STREET N HSEACO STREET Op -44k .... 25'SIDE SETBACK s { "� 50'SETBACK EAST OF .......: ~ s } CHARLES RIVER ROAD ` + u ` � '� � t= i � --�. ,, • � � t�,,, L'.S yr°��r* - �\ ''., .. � # Wit. _ Zoning Setbacks Plan ALEXANDRIA. PAGE150 4W Iw Aft ® � 00 00— 0 mm • `F 92.8' dL r� ' y, f • S7" fi` H ry 84.5' 46 25'-0"(Setback) �t L,L Building Height Analysis Arsenal on the Charles I April 8, 2021 PAGE 151 !pP RMI IL JIM F WN ar ir op- \ I I I I I ■ 411 w �I W- Architectural Precedent Images ALEXANDRIA. PAGE152 r• m79 k h�, 4 Architectural Precedent Images Arsenal on the Charles I April 8, 2021 PAGE153 M09 'M r In 14.k� I AN Ai ��> ` --� •.':.1 l Fist �� P. � !��1� T� � - -�, .. .I i 1 jj r y `,1 4 _ - __- - ` I � c � r� Arsenal Street . - I ��� •� Existing ter,. Bi ke Storage Eye obS y/ I ServiceDoor -�� a nt Pace s� I311 Arsenal I � I r 1 I f West Garage WooleygVen ue s +. 71 r 400 N. Beacon P► . L BIKE CONNECTION L IMPROVMENTS s- �+ �. \ "'`�; `• . N. aCo Sleet n Enlarged Illustrative Plan ALEXANDRIA. PAGE156 e �4 Naturalistic Plantings at Raised Planters - MA_ �� �( r Planters with Granite Seat Walls and Concrete Bollards at Drop-off Unit-pavers at Pedestrian Plaza and Shuttle Drop-off Landscape Precedents Arsenal on the Charles I April 8, 2021 PAGE157 Special Permit Supporting Statement I Per Section 9.05(B) of the town of Watertown Zoning Ordinance 1. Is the subject site an appropriate location for such use, structure, and/ The overall design expression of Site D is consistent with the standards or condition? YES/NO. Explain. identified in the Watertown Design Guidelines and Arsenal Overlay Development District (AODD), and will positively contribute to the YES. architectural evolution of the Arsenal on the Charles campus. Site D is located at northwest corner of the Arsenal on the Charles campus adjacent to the Arsenal Street entrance to the existing West 2. Will the proposed use/structures adversely affect the neighborhood? Garage. Site D is part of an extensive campus-wide masterplan that will YES/NO. Explain. redevelop it into a collaborative and innovative campus including life science, office, retail, and community uses, as well as publicly accessible NO. open spaces and streetscape improvements. The proposed building The proposed Project improves the edge of the campus by screening includes an enclosed, single-story pavilion with community-focused visible portions of the West Garage from Arsenal Street and creating programming as well as a new perforated metal, architectural screen a new pavilion with community-focused programming. The building is covering the north and portions of the east and west fagades of the setback from Arsenal Street to allow 311 Arsenal Street to maintain its existing garage. prominence along the thoroughfare. A new landscaped plaza improves the public realm to the north of the garage and softens the street edge Site D and associated landscape improvements (the "Project") have with a new vegetative buffer. been designed to activate an underutilized portion of the campus and to create a new attractive entry point from Arsenal Street. The building and The site lighting system will be designed to avoid visual impacts to the architectural screen have been designed to soften the exposed concrete abutters in compliance with the zoning requirements and Dark Sky fagade of the existing West Garage. At the center of the north fagade, Initiative. Mechanical systems will be high efficiency designed to operate the garage screen lifts to reveal an activated pavilion with transparent at 90-95% efficiency and to minimize noise levels. Acoustical engineering glazing that allows the building to engage the public realm and enable services have begun and will be continued throughout the design process. interior programming to visually "spill out" onto the plaza. The building's Evaluation of the rooftop and ground noise producing equipment will proposed height and setbacks comply with zoning and Arsenal Overlay be conducted. Equipment that exceeds comfortable noise levels for the Development District (AODD) design guidelines. adjacent residential properties will be properly screened and buffered with acoustical barriers. The architectural expression of Site D is inspired by its surrounding context. The rhythm of the folding metal screen panels echo the The Project will be designed to protect abutting properties from repetition of the window pattern found on the neighboring 311 Arsenal detrimental site characteristics resulting from the proposed use by building. At the base, timber-clad columns and beams with articulated implementing a stormwater management system which will reduce connections reference the common construction found in New England stormwater runoff and water pollutants. Construction related impacts, industrial buildings. The building is setback from Arsenal Street to allow such as dust and erosion, will be mitigated through the implementation of 311 Arsenal Street to maintain its prominence along the thoroughfare. a construction period Stormwater Pollution Prevention Plan (SWPPP). Special Permit Supporting Statement ALEXANDRIA, PAGE 158 3. Is there potential for nuisance or serious hazards to vehicle or 4. Will adequate and appropriate facilities be provided for the proper pedestrians? YES/NO. Explain. operation of the proposed use? YES/NO. Explain. NO. YES. As part of the masterplan, the campus circulation system will be The proposed development will be designed in accordance with the enhanced to maximize convenience and safety of vehicular, bicycle, and Massachusetts State Building Code, the Americans with Disabilities pedestrian movement within the campus and in relation to adjacent Act (ADA), Massachusetts Architectural Access Board (MAAB) and all streets and path connections. The proposed masterplan prioritizes the other relevant governing requirements. Additionally, the Project will flow and interaction of pedestrians and cyclists over motorized vehicles be designed to comply with the requirements of the Stretch Energy within the campus. The four main vehicular access points to the campus Code and will be certifiable with the USGBC for a LEED Gold rating. The will be maintained; however, the internal vehicular circulation will be attached LEED V4 scorecard describes the pathway to certification. enhanced to improve the pedestrian experience and facilitate better The proposed campus stormwater management system is designed to access to the retail and structured parking components. meet the Massachusetts Department of Environmental Protection's (DEP's) Stormwater Management Standards. With respect to the The proposed uses of Site D will reduce overall parking demand, allow for recharge requirements of Chapter 98: Stormwater Management and the reduction of parking from the previously approved plan and enable Erosion Control of the Town of Watertown's Code of Ordinances and the creation of a more pedestrian friendly, green campus. For enhanced the corresponding Rules and Regulations, the proposed stormwater safety, off-street building loading has been situated away from primary management system has been designed to the best extent practicable. vehicular and pedestrian corridors. The on-site circulation will create an Off site mitigation, including drainage improvements at the Commander's inclusive and accessible environment. All primary building access and Mansion and within Talcott Avenue, has been reviewed and coordinated internal site circulation will be ADA/MAAB compliant. with the Town. The system has been designed to be implemented in phases as individual building sites are developed on the Campus. Special Permit Supporting Statement Arsenal on the Charles I April 8, 2021 PAGE 159 Site Plan Review Statement I Per Section 9.03(C) of the town of Watertown Zoning Ordinance 1. Landscape: separates the pedestrian sidewalk from the shuttle drop off vehicular lane. The landscape associated with the Site D building (together, the "Project") includes a pedestrian plaza and shuttle drop-off, as well as a 2. Relation of Buildings to Environment: new streetscape along Arsenal Street. The pedestrian plaza and drop- off landscape are part of the broader Arsenal on the Charles campus In addition to a new landscaped plaza at the edge of Arsenal Street, enhancements project, which employs a consistent language of granite the Site D Project proposes a dynamic addition to the existing West planters, seating elements, and pavements which unify the campus Garage that includes a new architectural screen and an enclosed, single- landscape, and offer human scale areas for gathering and enjoying the story pavilion with community-focused programming. The proposed outdoor public realm of the campus. perforated metal architectural screen will cover the north and portions of the east and west facades of the existing garage. The design will focus on Fixed bollards and granite seat-walled planters separate the drop off from sustainability and energy conservation with a goal of achieving a Net Zero the pedestrian plaza in front of the building, and also act as a vehicular Energy Building certification. deterrent. Lush native and adapted perennials, shrubs, and trees are planted in these planters. The same unit pavers that exist today along the The architectural expression of Site D is inspired by its surrounding service drive west of 311 Arsenal Street are used in the new vehicular and context. The rhythm of the folding metal screen panels echo the pedestrian zones, purposefully unifying the site. repetition of the window pattern found on the neighboring 311 Arsenal building. At the base, timber-clad columns and beams with articulated Vehicular access for shuttles into the new drop off is provided via the connections reference the common construction found in New England existing garage entry/exit drive at the existing signalized intersection, and industrial buildings. The building is setback from Arsenal Street to allow shuttles exit the drop-off via a new curb cut near the northwest corner 311 Arsenal Street to maintain its prominence along the thoroughfare. of the 311 Arsenal Street building, which today has a rolled curb for fire access. The vehicular entry point will be demarked with signage indicating The Project is designed to celebrate the public realm and to create a new that the drop-off is to be used only by shuttles. The exit from the drop-off activated entry point to the campus from Arsenal Street. At the center will be signed as right turn only. Service access for Building D is provided of the north facade, the garage screen lifts to reveal an activated pavilion from inside the West Garage. Service access into an existing loading door with transparent glazing that allows the building to engage the public in the west facade of the 311 Arsenal Street building is maintained. Fire realm and enable interior programming to visually "spill out" onto the and emergency vehicle access between Building D and 311 Arsenal will plaza. The location of the lift provides a focal point to the facade and also be maintained. introduces a dynamic quality to the folding metal garage screen. A new sidewalk, tree lawn, street trees, and brick paving strip—all Town The materiality for Site D draws inspiration from the Arsenal-on-the- of Watertown standard —are provided along Arsenal Street, consistent Charles campus by recalling the rich history of metallurgy and material with the streetscape along this road corridor. A planted strip also exploration found on site through the integration of industrial accents Site Plan Review Statement ALEXAN DRIA. PAGE 160 and details into the facade. The sense of movement generated by the The on-site circulation will be an inclusive and accessible environment. lift in the folding metal garage screen celebrates the dynamic qualities of Internal circulation will be ADA/ MAAB compliant. Emergency access to the material. The wood-clad columns and accents provide warmth to the the site will be provided utilizing the existing street network and drop off building's base and compliment the materiality of adjacent structures. lanes, as well as the combined bikeway and pedestrian access along the A high-performance curtainwall system maximizes the building's energy west side of the West Parking Garage. Fire lanes in the form of shared performance. All selected materials are durable, resilient, natural and streets and paths surrounding the Site D building have been provided. sustainable. Off-street loading has been maintained in the alley between the proposed Site D Building and Building 311. The comprehensive design for the building addition and landscape improvements as part of the Site D Project are informed by the formal design review completed pursuant to Section 9.03(d) and is consistent 5. Surface Water Drainage: with the standards identified in the Watertown Design Guidelines and Arsenal Overlay Development District (AODD), specifically as related The proposed surface water drainage system is designed to meet the to the building scale, massing, setbacks, architectural expression and Massachusetts Department of Environmental Protection's (DEP's) landscape design. Campus site improvements to the public realm beyond Stormwater Management Standards. With respect to the recharge the limit of work line will be addressed in the Masterplan Special Permit requirements of Chapter 98: Stormwater Management and Erosion Application package filed separately. Control of the Town of Watertown's Code of Ordinances and the corresponding Rules and Regulations, given extensive environmental 3. Open Space: limitations throughout the campus site, the stormwater management system meets the infiltration design criteria to the best extent practicable. The drop-off and pedestrian plaza are publicly accessible and visible from The system has been designed to be implemented in phases as individual Arsenal Street. The open space surrounding the building is part of the building sites are developed on the Campus. broader Arsenal on the Charles campus enhancements project; please refer to the master plan special permit amendment for campus-wide The stormwater management system for the proposed Site D building open space calculations. addition builds upon the overall stormwater management strategy for the approved Campus Enhancement Plan. Runoff from existing paved 4. Circulation: areas (including the West Parking Garage roof deck) will continue to be treated and detained in various BMP's recently installed as part of the A new shuttle drop off will be provided to support a transit center use of West Garage Project. Runoff from newly paved areas subject to vehicular the Site D Building project. Vehicular and pedestrian separation has been traffic will be pre-treated with water quality structures. Upon meeting increased between the drop off area and the adjacent sidewalk along the water quality treatment requirements, runoff will be directed to a Arsenal Street. A one-way traffic pattern is provided at the shuttle drop- centralized subsurface, water-tight, precast detention systems located off. south of the West Parking Garage structure. This portion of the campus Site Plan Review Statement Arsenal on the Charles I April 8, 2021 PAGE 161 stormwater network discharges to an existing drainage system in North Beacon Street. Campus Enhancement Plan Phasine The Campus Enhancement Plan documented a complete stormwater management system following full implementation of all project The following stormwater design features of the stormwater management phases. The Project's stormwater management system is designed to strategy from the Campus Enhancement Plan are included in the surface accommodate stormwater runoff from areas of the Campus included in water drainage system for Site D. this Project phase. Subsurface Detention Svstems 6. Utility Service: The Campus Enhancement Plan calls for the installation of three (3) new subsurface detention systems as well as maintaining existing There is adequate capacity in existing utility infrastructure to service detention systems that would retain stormwater and gradually release the campus. All electric, telephone, cable TV and other communication runoff at a controlled rate. The Project's existing subsurface detention distribution and service infrastructure will remain underground on the system network located within the west driveway to the West Parking Campus Plan site. As individual building sites are developed, electric and Garage and south of the West Parking Garage will be maintained and communication duct banks, conduits, wires and cables will be evaluated reconfigured to accept runoff from the Site D site improvements. Outlet and repaired or replaced as required . control structures that maximize storage capacity within each system further reduce the peak rate of runoff leaving this portion of the site. Additional building expansion at the West Parking Garage was considered at the time when the garage project was completed. Accordingly, new Water Qualitv Units water and sanitary sewer service connection were provided and capped The Campus Enhancement Plan includes water quality structures and for a future project. The Site D building project includes new water and various BMP's to capture stormwater runoff from all paved areas for sanitary sewer connections to the existing capped connections provided. vehicular use to provide treatment prior to detention/infiltration and The existing water distribution system at Site D has sufficient pressure subsequent discharge to the municipal drain systems. The Site D Building and supply for the new proposed building. Proposed sanitary sewer flow and site improvements include two (2) water quality units to treat from the Site D Building addition will be directed to the Arsenal Street stormwater runoff in the paved portions of the Project area prior to collection system. collection in the subsurface detention system. Electric Pervious Pavers The existing infrastructure at or immediately adjacent to the Project Site The Campus Enhancement Plan describes the expansion of pervious areas based on current uses is believed to be adequate to support the Project. throughout the campus. The paved areas adjacent to the proposed Site D The Project will be served from existing on-campus infrastructure. Building includes about 5,000 SF of pervious pavers to contribute to the Electric service to the campus comes from underground feeds in both overall campus strategy to reduce impervious areas. North Beacon Street and Arsenal Street. The provider for this utility is Site Plan Review Statement ALEXAN DRIA. PAGE 162 Eversource. Location and Transportation: LEED credits in this category are awarded based on existing community Telecom/Data infrastructure and services. In addition, LEED v4 added a significant Based on review of utility plans provided by Verizon and Comcast, amount of requirements to credits in this category. Because the project it is VHBs understanding that both Verizon Fios and Comcast fiber site is on a campus and in the heart of Watertown, several credits are telecommunications and data services are available in the area. Service available. will be drawn from existing on-campus infrastructure. The project is adjacent to an existing garage and is on previously 7. Environmental Sustainability: developed land, which will result in one point for the Sensitive Land Protection credit. In addition, the project site is adjacent to a variety The projects goal is to provide both an energy-conscious building and of community amenities and has a Walkscore of 79, which will earn significant site improvements that address environmental sustainability the project three points for Surrounding Density and Diverse Uses. An and conservation of resources. Making sustainable choices for the built additional one points will be achieved in the same credit rewarding the environment requires the collaboration of all design disciplines in an project for being sited in an area with relatively high FAR. integrated process. To that end, the team has held sustainability-focus meetings to define the project sustainability goals and outlining tasks and Although there are bus stops on Arsenal Street, only Line 70 runs past responsibilities going forward. these bus stops. This provides 86 weekday and 64 weekend trips, which is sufficient to earn one point in the Access to Quality Transit credit. Under The projects will demonstrate compliance with the Section 7 the LEED v4.1 methodology, it may be possible for private shuttles to Environmental Sustainability criteria and the LEED Gold Certified further contribute, which may result in an additional point. requirement using the LEED version 4/4.1 New Construction Rating System. At this time, the project is tracking 70 points as "Yes" with an The project is adjacent to an existing bike network, including bike lanes on additional 10 "Maybe" points, therefore exceeding the required 60-point Arsenal Street and the Watertown Greenway. The project is also providing Gold threshold. Please see the included scorecard. interior bike storage, however because there is a desire to not provide a shower for security reasons the Bicycle Facilities Credit is not likely to Below is a section-by-section breakdown detailing the project's approach: be achieved. The team is providing Bike Rental at the building and will attempt an alternative compliance path. Integrative Process: The project team has been using an integrated process and opportunities Demonstrating compliance with the Reduced Parking Footprint and Green to achieve synergies across disciplines and building systems. Early energy Vehicles credits can prove challenging on campus settings due to the modeling efforts are underway and a water balance is being explored. The nature of shared parking which means that all campus parking should be project anticipates one point for this credit. included. The campus is anticipating 2,812 parking spaces this is in excess of the threshold for the Reduced Parking credit. The project is evaluating Site Plan Review Statement Arsenal on the Charles I April 8, 2021 PAGE 163 the feasibility of earning the LEED Green Vehicles credit through either Significant water metering will be planned, including water used for a single building or campus approach by and is holding the credit as irrigation and domestic hot water. One point is available if two of these "Maybe." systems are separately metered under the Water Metering credit. Wherever possible, native and adapted plantings that require limited Sustainable Sites: irrigation are being used. This will allow the project to earn one point in The project team has spent significant time reviewing existing site the Outdoor Water Use Reduction credit. A cooling tower is not planned conditions in relation to topography, hydrology, climate, vegetation, for the project so the associated credits are not available. soils, human use, and human health and will earn one point for the Site Assessment credit. Enerav and Atmosphere: The project is evaluating HVAC systems and looking to include The campus has significant green space with pedestrian amenities, which photovoltaics (PV) on the adjacent garage roof to support a Net Zero will be enhanced through the development process, meeting the intent Energy (NZE) goal. The project is planning an all electric highly efficient for the Open Space credit. However, the limited area of site disturbance VRF system, the project is currently holding all 18 points in "Yes" for may not allow formal compliance and therefore this credit is not targeted. Optimize Energy Performance. The PV system and NZE project goal The site is adjacent to an existing parking garage, and as a result, one will support the achievement of three points in the Renewable Energy point for the Heat Island Reduction credit is anticipated for providing Production Credit. parking in a structure. The unique "roof" of the building may make demonstrating compliance challenging and for this reason the second Building commissioning helps ensure that the building meets set credit is being held as a "Maybe." performance goals. LEED v4 offers credits for both building system and envelope commissioning, and enhanced and monitoring-based Due to somewhat limited site disturbance related to development on commissioning are planned for the project. Envelope commissioning is an existing campus, neither the Rainwater Management nor the Site also planned. Development credits are being targeted. The project plans on earning one point for the Light Pollution Reduction credit through selection of A credit is available if the project meters all building end energy uses dark sky compliant fixtures and care in location of site lighting. of more than 10%, this is being held as a "Maybe" under the Advanced Energy Metering Credit. Water Efficiencv: Alexandra Real Estate offsets its energy use with Green Power purchases, A high level of water savings is anticipated using low flow aerators on and therefore the project is anticipating two points in the Green Power sinks, low flow toilets and urinals. Depending on final occupancy, these and Carbon Offsets credit for purchasing RECs and carbon offsets for fixtures in combination will result in 30%to 35% water savings, earning 100% of the energy use for 5 years. the project 2-3 points. Water Sense Labeled fixtures will be specified where eligible, as LEED v4 requires this. The project is planning a VRF system so the Enhanced Refrigerant Management Credit more challenging, although the team is evaluating 0 Site Plan Review Statement ALEXAN DR IA. PAGE 164 a hydronic hybrid VRF system which could limit refrigerant and allow under the Indoor Air Quality Assessment credit, with a second point as achievement of the credit. The Demand Control credit requires significant "Maybe" if the team decides to pursue a testing option. load shedding but for this building type is likely achievable with through a combination of increased set points and reduced lighting power. Care in material selection is critical for optimizing credits in this category. Unlike LEED 2009, v4.0 & v4.1 looks at emissions of materials, beyond Materials and Resources: VOCs. LEED v4.1 provides opportunities for teams to earn more credits One of the most significant changes in LEED v4 is in the Materials and than were available in LEED v4.0, and this path will be pursued. The Resources section. The focus has changed from materials themselves project will target paints and coatings, composite wood, flooring, ceilings, to material transparency. Manufacturers are quickly adapting to this and insulation for these credits, and anticipates earning all three points in change, with more of the information required to earn these credits the Low-Emitting Materials credit. becoming available as more EPDs, HPDs, and CSRs are developed. The project will target a minimum of 20 EPDs and 20 HPDs in addition to The project anticipates earning the Thermal Comfort credit and also sourcing materials with sustainability attributes (i.e. recycled content, FSC the controllability point for the Interior Lighting Credit. The team will wood, rapidly renewable material, C2C certification). This will allow the evaluate the newly released LEED v4.1 Quality lighting option for this project to earn one point in each of the following Building Discloser and credit, which is currently held as a "Maybe." The Acoustic Performance Optimization credits: Environmental Product Declarations, Sourcing of credit has also recently been updated and is also being held as a "Maybe" Raw Materials, and Material Ingredients. currently. The project will have excellent views and is anticipated to earn the point for the Quality Views Credit. A whole building life cycle assessment provides the team an understanding of the environmental impact of the project construction. Innovation: This study will be conducted and will earn the project three points for The project anticipates earning all credits in the Innovation and Design the Life-Cycle Impact Reduction credit. In addition, the project will target Category. These credits will be selected to help the project tell the story Construction Waste Recycling with 75% diversion, including three waste that the client is most excited about. Although these credits have yet to streams, to earn two points in this credit. be selected, they may include the following: • Walkable Project Site Indoor Environmental Qualitv: • Designing for Nature The Enhanced IAQ Strategies credit will be targeted with a focus on • Design for Active Occupants filtration, walk off mats, exhausting chemical storage rooms. This will earn • Green Building Education the project one point, and a second point for providing demand control • O+M Starter Kit ventilation is planned. In addition, the Construction IAQ Management • Integrated Analysis of Building Material Plan credit will be targeted, and the specifications will require the • WELL Credits construction team to develop and implement a plan. An additional point • Fitwel Credits will be available for conducting a building flush and is being held as "Yes" • Occupant Survey Site Plan Review Statement Arsenal on the Charles I April 8, 2021 PAGE 165 The Project site is accessible from Arsenal Street via the West Garage Regional Prioritv: entrance driveway and shuttle drop-off lane that runs parallel to the The following credits are regional priorities. Additional points are north facade of the garage. The campus is accessible by emergency available for these credits if they are earned at the listed thresholds: vehicles from Arsenal Street via Kingsbury and Talcott Avenues as well as • Rainwater Management (3 points) from North Beacon Street via School Street. Fire truck access is around • Optimize Energy Performance (8 points) the perimeter of the building as indicated in the Fire Truck Maneuvering • Building Life Cycle Impact Reduction (3 points) figure attached. • Indoor Water Use Reduction (3 points) • Renewable Energy Production (2 points) The existing West Garage has three separate egress stairs. All exits lead to • High Priority Sites (2 points) an easily identifiable open space away from the building. All exits within the one-story Site D addition will be clearly marked as required by code. 8. Screening: 10. Design: The previous masterplan for Arsenal-on-the-Charles proposed a 3-story building to the north of the West Garage (previously referred to as The Project will be designed to protect abutting properties from Building 2). This building was unrealized and the facade of the West detrimental site characteristics resulting from the proposed use by Garage facing Arsenal Street remains largely unscreened. implementing a stormwater management system which will reduce stormwater runoff and water pollutants. Construction related impacts, The Project screens visible portions of the West Garage from Arsenal such as dust and erosion, will be mitigated through the implementation of Street with a new folding metal architectural screen. Additionally, a new a construction period Stormwater Pollution Prevention Plan (SWPPP). landscaped plaza improves the public realm to the north of the garage and softens the street edge with a new vegetative buffer. The previous masterplan for Arsenal-on-the-Charles proposed a 3-story building to the north of the West Garage (previously referred to as Service access to the Site D building will be provided from within the Building 2). This building was unrealized and the facade of the West existing West Garage; the building does not have an external loading Garage facing Arsenal Street remains largely unscreened. The proposed dock. Views from Arsenal Street to the existing service door on the west Project is smaller in scale than what was previously proposed and screens facade of the 311 Arsenal building are screened by the eastern planter in visible portions of the West Garage from Arsenal Street with a new the pedestrian plaza, which is planted with perennials, shrubs, and trees. folding metal architectural screen. The building is setback from Arsenal Street to allow 311 Arsenal Street to maintain its prominence along the thoroughfare. A new landscaped plaza improves the public realm to the north of the garage and softens the street edge with a new vegetative 9. Safety: buffer. The site lighting system will be designed to avoid visual impacts to the abutters in compliance with the zoning requirements and Dark Sky 0 Site Plan Review Statement ALEXAN DR IA. PAGE 166 Initiative. Mechanical systems will be high efficiency designed to operate at 90-95% efficiency and to minimize noise levels. Acoustical engineering services have begun and will be continued throughout the design process. Evaluation of the rooftop and ground noise producing equipment will be conducted. Equipment that exceeds comfortable noise levels for the adjacent residential properties will be properly screened and buffered with acoustical barriers. See Renderings showing the new building in the surrounding context for reference. Site Plan Review Statement Arsenal on the Charles I April 8, 2021 PAGE 167 w. P i • Arsenal 1 PAGE •i Building Massing & Setbacks 1 REFERENCING SCALE The folding, perforated metal screen wraps the existing West Garage, which closely aligns to the height of the 311 Arsenal Street. The folding pattern on the screen follows a similar rhythm to the repetitive window spacing found on 311 Arsenal Street. 2 VERTICAL ELEMENTS The panels on the garage screen are organized into a vertical folding pattern, which breaks up the horizontality of the facade. 3 MASSING VARIATION The lifting base reveals an activated 4 base that engages the round lane 9 p 11. 1iy 4 I and provides porosity to the existing imposing garage facade. The location of the lift provides a focal point to the facade and introduces a dynamic quality to the screen. 4 SETBACKS The building is setback from Arsenal Street to allow for a landscaped plaza at the street's edge that functions as an intermodal transportation hub. The setback allows 311 Arsenal Street to maintain its prominence along the thoroughfare. AODD Design Guidelines Summary Arsenal on the Charles I April 8, 2021 PAGE169 Building Height 1 UPPER STORY SETBACKS As the garage screen lifts, it slopes away from the base diminishing the overall scale of the building. From the ground level perspective, this gesture emphasizes the human scale of the enclosed pavilion space rather than the overall garage screen. 2 REFERENCES TO CONTEXT Two key elements of the building e reference its historic surroundings. First, the folding pattern on the screen follows a similar rhythm to the repetitive window F spacing found on 311 Arsenal Street. Second, the use of timber-clad columns and beams with articulated connections is a reference to the common construction s. found New England industrial buildings. g g _ 3 GROUND FLOOR OVERHANG The recessed ground floor facade protects pedestrians from the elements, reduces solar gain, and delineates the base of the building from the garage screen above. AODD Design Guidelines Summary ALEXANDRIA. PAGE 170 Facade Treatment & Materials 1 HIGH QUALITY AND NATURAL MATERIALS The material palate for Site D celebrates the industrial heritage of the Arsenal on the Charles campus. The perforated metal garage screen complements the industrial aesthetic of the site and references the site's rich history in material exploration. �4 The wood columns with articulated joinery 0 reference heavy timber construction. A v © high-performance curtainwall system maximizes the building's energy performance.All selected materials are V durable, resilient, natural and sustainable. TEXTURE, VARIATION,AND TACTILITY 2 Ashifting horizontal datum separates the two differing facade treatments that �uf iiy y together foster a balanced composition. Above, the folding perforated metal panels a --T provide interest through the interplay of light and shadow and are ever evolving 9 through the day. Below, selected wood materials celebrate variations in tone and texture and provide a warmth to the facade. TRANSPARENCY AT GROUND LEVEL 3 Transparent glazing at the enclosed pavilion space allow the building to engage the public realm and enable interior programming to visually"spill out"onto the street front plaza. Ground floor uses focused on activating both the interior and exterior allow the building to become a welcoming focus point. AODD Design Guidelines Summary Arsenal on the Charles I April 8, 2021 PAGE 171 I Chapter Building 1 Project Narrative Supporting Site Plan Review Approval of Phase 2 of the Campus Master Plan T■ ' g ek 14 i• �-" ,�3. '�- Y.="� � t, f�A4. i°:,4�. y� q9+� .,,� ?f116v K'}b.t � }y ���-ry�� tJF •� j I I . ■ ... 5 .im Approval Summary Chapter Contents The Petitioner, Alexandria Real Estate Equities, Inc., requests a Final Site • Enlarged Site Plan Plan Review for Phase 2. Phase 2 will comprise of Building 1 and Building • Zoning Summary 2, new four-story office and research laboratory buildings and related • Architectural Precedent Images site enhancements. Narrative information supporting the Final Site Plan • Renderings Review Approval for Building 1 is located in this chapter. • Special Permit Supporting Statement • Site Plan Review Statement Building 1 is a four-story office and research laboratory building located at • AODD Design Guideline Summary the heart of the Arsenal on the Charles campus. The project also includes the addition of photovoltaic panels to the roof of the existing East Garage. The building will be designed to achieve LEED Gold and FitWel certification. ALEXAN DR IA. PAGE 174 VVOOLEYAVEN UE -------------- NEW PROGRAMMING IN EXISTING a \ ��/__\�� ► , GARAGE AT GROUND FLOOR ONLY ♦ 400 N. BEACON `aF BLDG 1 EAST PARKING E - GARAGE o--NEW PROGRAMMING IN EXISTING ---- \ GARAGE AT GROUND FLOOR ONLY NpRTy gF ` , ; n9 N STREET - - &`Z. LOADING , .� r DOCK rds . . . . . � Building 1 Site Plan Arsenal on the Charles I April 8, 2021 PAGE 175 -41 0 zo -. ARSENAL STREET v REET _ _ -- I ---••25'SIDE SETBACK r AT ARSENAL STREET - - - ' 25'SIDE SETBACK•••••••• a - Or 25'OR 45 DEGREE PLANE••---•-• NORTy FROM EDGE OF STREET BEACON STREET a, a -.vrC- al s� �r..:- - t • { e c ---- 25'SIDE SETBACK - r f yea � • 50'SETBACK EAST OF -•-•-•-� _ CHARLES RIVER ROAD , 't * f ❑ e !r `C:. �.- \r Zoning Setbacks Plan ALEXANDRIA. PAGE 176 � ,, f � •�� �E, `i t6 1 r 1 F � rr - •� jiMr'� EF Fri Op or 0. .�rool�� " Mechanical Penthouse T 24'-0" W i 24'-0" 1•. W 24' --�- ` ,. lir 3f �45c . 50'-0"(Setback) Building Height Analysis Arsenal on the Charles I April 8, 2021 PAGE 177 r i � Illl� l � llllh� i�� il � II it � � - - - - I r� 1 .. fl l " I � - '��� uE ��'�:+:e�}�' v 4�4K1 .�n�{� ��� 'ry � � r�� `'t� � •'�;`.y ,�"�'- ° 39 � G - r Building 1 from Wooley Avenue Arsenal on the Charles I April 8, 2021 PAGE 179 Arsenal I_ � _' ^. 3�ry4 .f=may;•+a'w'• . -l .� ,�•. � - _-� - <s i tir. Building 39 • �' }4~ rt , AlaftI Y77 IIIII . . wBuilding Overhang P' CAM Vs !, East �'� •. 3 400 N. Garage D Beacon ±;r ID M. v [awry.. Reconfigured V Garage ° �. Building 1 Entrance/Exit i J - t Bra chl'n as N Bacon tQ`° et UtI'lit Reconfigured <'is Enclosre Garage �eS Entrance/Exit G,�at �„ t �'��,��" �' F Wit' •��. -;. � Entrance/ t� 9 `LIL a day ` I Kingsbu p-, u7 ` .►�� •` �, : �� g Transformers Off Cdirt � V ti �t f f oading All.7 r re I 1 Kingsbury € Enlarged Illustrative Plan A L E X A N DRIA. PAGE 180 --z - C , r: .'�;: � •. � �f•.. _ .�� ,:ram:- �_�,. ;y� i ,.ter. � '� �rk$' #��• �.-"�. f r .� - �i '"- - I ^t _ v .J-� 1.-. # �ryi� ef'i.- A - ^...i .y ✓ r *%dw Ti . Ail 'Now _E t q� r7 1 r. z ! F t � �'� ��'d� �° _.��."�.- .dy. c.: ''�'-���0. F '��"'':"L.'� y+�"+k..t 'r.'> $z -F a' �j4j .•�'•�� '{�' � s�.a Y's2*�6,8. j ' I.. ��. { :�, R „�yi.. 1J .z 'A,�_ .� `.� .�yfi* `� '`tr��, a .�$'{r + �.� •��rs.P.�. OT ff ,`,, #'arm `t ,- y -b YJ_{. t1S„ 5 F i B t•Y *' .a. iOUT. , 101 W44 �vt low '�,*F!�4- t is �^' ,M r�xs•�� E i � F n �' !� t,Y..� �t17..:wr.'..<"c..'?'"z� � +`�t� 9.•r as .:, Ot"t"�.�.aa�"c.: _ Special Permit Supporting Statement I Per Section 9.05(B) of the town of Watertown Zoning Ordinance 1. Is the subject site an appropriate location for such use, structure, and/ 2. Will the proposed use/structures adversely affect the neighborhood? or condition? YES/NO. Explain. YES/NO. Explain. YES. NO. The Building 1 site is located at the heart of the Arsenal on the Charles The placement of the building was carefully considered and designed campus. Building 1 is part of an extensive campus-wide masterplan that to minimize impacts to the adjacent neighborhood, integrate into will redevelop it into a collaborative and innovative campus including life the historic fabric of the campus and respect the site's topography. science, office, retail, and community uses, as well as publicly accessible Efforts were taken to mitigate the building's impact on surrounding open spaces and streetscape improvements. The proposed building is neighborhoods, including breaking down the building's mass by consistent in use with several nearby office and research + development organizing it into two primary sections and by following the 50-foot buildings that have contributed to a significant lab/ R&D cluster along zoning setback to preserve the riparian corridor along North Beacon Arsenal Street. Street and the river's edge. Furthermore, the vertical fins on the Building 1 and associated landscape improvements (the "Project") have building's primary facade will mitigate evening light emanation from been designed to integrate into the existing fabric of the historic Arsenal interior program spaces. on the Charles campus. The building has been positioned the shield the west facade of the existing East Garage from view and to activate the The site lighting system will be designed to avoid visual impacts to the edge of the newly designed publicly-accessible greenspace at the center abutters in compliance with the zoning requirements and Dark Sky of the campus that will be improved as part of the AOTC masterplan. The Initiative. Mechanical systems will be high efficiency designed to operate building's proposed height and setbacks comply with zoning and Arsenal at 90-95% efficiency and to minimize noise levels. Acoustical engineering Overlay Development District (AODD) design guidelines. Its massing services have begun and will be continued throughout the design process. is formed by the intersection of two linear volumes that generate a Evaluation of the rooftop and ground noise producing equipment will composition that breaks down the overall building scale and diminishes be conducted. Equipment that exceeds comfortable noise levels for the its apparent height. adjacent residential properties will be properly screened and buffered with acoustical barriers. The materiality for Building 1 draws inspiration from the Arsenal on the Charles site and integrates fagade elements that celebrate the campus' The Project will be designed to protect abutting properties from industrial past. The angled copper-tone sun shading fins reference detrimental site characteristics resulting from the proposed use by the site's rich history of industry and metallurgy. Selected natural implementing a stormwater management system which will reduce materials such as wood and stacked masonry echo the variations in stormwater runoff and water pollutants. Construction related impacts, tone and texture found in the heavy masonry architecture of adjacent such as dust and erosion, will be mitigated through the implementation of structures. The overall design expression of Building 1 is consistent with a construction period Stormwater Pollution Prevention Plan (SWPPP). the standards identified in the Watertown Design Guidelines and Arsenal Overlay Development District (AODD), and will positively contribute to the architectural evolution of the Arsenal on the Charles campus. Special Permit Supporting Statement ALEXANDRIA, PAGE 184 3. Is there potential for nuisance or serious hazards to vehicle or The proposed campus stormwater management system is designed to pedestrians? YES/NO. Explain. meet the Massachusetts Department of Environmental Protection's (DEP's) Stormwater Management Standards. With respect to the NO. recharge requirements of Chapter 98: Stormwater Management and As part of the masterplan, the campus circulation system will be Erosion Control of the Town of Watertown's Code of Ordinances and enhanced to maximize convenience and safety of vehicular, bicycle, and the corresponding Rules and Regulations, the proposed stormwater pedestrian movement within the campus and in relation to adjacent management system has been designed to the best extent practicable. streets and path connections. The proposed masterplan prioritizes the Off site mitigation, including drainage improvements at the Commander's flow and interaction of pedestrians and cyclists over motorized vehicles Mansion and within Talcott Avenue, has been reviewed and coordinated within the campus. The four main vehicular access points to the campus with the Town. The system has been designed to be implemented in will be maintained; however, the internal vehicular circulation will be phases as individual building sites are developed on the Campus. enhanced to improve the pedestrian experience and facilitate better The proposed landscape will be preserved in its natural state, insofar access to the retail and structured parking components. as practicable, by minimizing tree and soil removal. Minimal grade changes will insure that the overall landscape will be in keeping with The proposed uses of Building 1 will reduce overall parking demand, the general appearance of neighboring developed areas. Adequate allow for the reduction of parking from the previously approved plan landscaping will be provided, including screening, provision of street and enable the creation of a more pedestrian friendly, green campus. trees, landscape islands in the parking lots and a landscape buffer along For enhanced safety, off-street building loading has been situated away the street frontage as needed. While being respectful of the importance from primary vehicular and pedestrian corridors. The on-site circulation of this component of the overall landscape plan, the Plan will incorporate will create an inclusive and accessible environment. All primary building compelling site features throughout the campus that will complement access and internal site circulation will be ADA/MAAB compliant. the overall character. In addition, the Plan provides significant screening of adjacent residential areas, incorporates significant trees along internal 4. Will adequate and appropriate facilities be provided for the proper streets and green spaces and a robust buffer along the street frontage. operation of the proposed use? YES/NO. Explain. Other landscape enhancements will include rain gardens, the use of native plant materials and urban agriculture feature including a working YES. orchard. The proposed development will be designed in accordance with the Massachusetts State Building Code, the Americans with Disabilities The proposed site plan is part of a long term comprehensive landscape Act (ADA), Massachusetts Architectural Access Board (MAAB) and all and integrated stormwater strategy for the campus. Currently, there are other relevant governing requirements. Additionally, the Project will several mono-cultures of tree plantings and our strategy is to develop be designed to comply with the requirements of the Stretch Energy a diverse, more naturalistic and native plant palette that improves the Code and will be certifiable with the USGBC for a LEED Gold rating. The aesthetics and habitat of the campus. The proposed revitalization will attached LEED V4 scorecard describes the pathway to certification. preserve and protect the most significant existing trees, while improving Special Permit Supporting Statement Arsenal on the Charles I April 8, 2021 PAGE 185 pedestrian plaza areas, walkways, and internal vehicular circulation, as well as courtyard and buffer plantings. The Plan takes advantage of its relationship to the Olmsted historic landscape at the east portion of the property along Talbot Avenue and on the abutting property of the Town of Watertown. Additionally, the proposed strategy also maintains and enhances the character of the landscape bluff to the South and the monumental iron fencing that borders the majority of the Campus Special Permit Supporting Statement ALEXAN DRIA. PAGE 186 Site Plan Review Statement I Per Section 9.03(C) of the town of Watertown Zoning Ordinance 1. Landscape: the new building loading dock will receive delivery vehicles coming from Kingsbury Avenue. The loading area is depressed four feet below The landscape associated with Building 1 (together, the "Project") is part the finished grade of the building, allowing trucks to access the loading of the broader Arsenal on the Charles ("AOTC") campus enhancements dock at the desired elevation. New transformer utilities associated with project, which employs a consistent language of granite seating elements Building 1 are located within the walled loading area. Retaining walls, and edges, unit pavements, and robust planting which unify the campus flush with the landscape to the south, separate the loading area from the landscape, and offer human scale areas for gathering and enjoying the adjacent landscape. 42" screen walls mounted on top of the retaining outdoor public realm of the campus. walls provide fall protection and visual screening at the loading dock edge. The loading dock is further separated from the community path by Landscape surrounding Building 1 a landscape buffer planted with shrubs and trees. The Building 1 front door is located in the center of the west facade, aligned with a primary pathway leading from the drop-off court to the School Street Improvements and New Drop-Off Court west between the gardens and event lawn. Visitors to the building can School Street is realigned and smoothed out to a continuous slope to be dropped at the large drop-off to the west on School Street, as well as provide atree-lined boulevard into the campus off of North Beacon within the East Garage, which is connected to Building 1. Street. A planted bioswale is located in the boulevard's planted median, North of the front door, along the west facade, the building overhang receiving surface stormwater runoff from adjacent paved surfaces. creates a covered area for tables and chairs where the Building 1 tenants Evergreen tree planting west of School Street will screen the loading area may extend their collaborations outdoors. Along Wooley Avenue, a new for the 300 North Beacon Street building, which is also held at a lower expanded sidewalk, clearly marked crosswalks, and street trees enhance elevation than School Street. At the north end of School Street the grade the pedestrian-friendly nature of the streetscape. levels off, a new vehicular arrival court allows for rideshare and personal vehicle drop off in the center of the campus, with proximate access to the South of the entry plaza, a linear bioretention basin wraps the west 311 Arsenal Street building, 400 North Beacon Street building, and new and south facades, receiving stormwater from the roof of the existing Building 1. The arrival court is curbed and paved in concrete unit pavers east garage that is conveyed under the new building. This feature is with a planted bioretention area in the center of the turnaround. coordinated with the stormwater management strategy for this area of the campus. The bioretention area is planted with a mix of native grasses, Woolev Avenue Improvements perennials, and shrubs that are well-suited to inundation and help to filter Wooley Avenue is rebuilt with wider sidewalks and planted buffers the roof runoff water. between the sidewalk and the curb. Where subsurface utilities allow, new street trees frame the corridor. A new loading dock is carefully integrated Along the south facade, east of the bioretention basin, service and egress into the south facade of 311 Arsenal Street. A drop-off lane on the south doors connect to a service pathway that is separated from the community side of the Wooley Avenue streetscape accommodates the turning path by a landscape buffer planted with shrubs and trees. Away from the movements of vehicles pulling into the interior loading bay. event lawn, farther to the east and immediately south of the East Garage, Site Plan Review Statement Arsenal on the Charles I April 8, 2021 PAGE 187 Campus Heart Landscape bar is a three-story angled projection featuring a seamless curtainwall The landscape around 400 North Beacon Street is enhanced to support that is bordered by a wood and dark metal frame. The angle of this special events and day-to-day activities in the center of the campus. West volume is parallel to the footprint of 400 North Beacon and orients the of 400 North Beacon, the existing surface parking lot is replaced with a view of the Event Lawn toward the Charles River. At the convergence of lawn with paths that draw pedestrians into the campus heart. Informal the two volumes is a carved recess that defines the building entrance. tree planting reinforces the ecological corridor along the southern edge Together, the two volumes form a composition that breaks down the of the campus. North of 400 North Beacon, a new pavilion offers shade in overall building scale and diminishes its apparent height. summer and protection from the elements year-round over a large plaza populated with movable tables and chairs. East of the pavilion, small The materiality for Building 1 draws inspiration from the Arsenal on outdoor rooms defined by sculptural granite seat edges are embedded the Charles site. The angled copper-tone fins reference the site's rich in sensory garden plantings. An open lawn area is maintained south of history of industry and metallurgy. The blackened steel frame, wood the gardens to accommodate large events. The existing screened utility soffit and stacked linear brick are a modern reference to the existing enclosure east of 400 North Beacon is expanded. The existing stonedust vernacular architecture on site. A high-performance curtainwall system path along the southern edge of the campus is maintained and enhanced maximizes the building's energy performance. Differing facade treatments with additional tree and shrub planting, as well as new LED lighting. emphasize the two primary volumes of Building 1 and generate a balanced composition. Selected natural materials such as wood and 2. Relation of Buildings to Environment: stacked masonry celebrate variations in tone and texture. The angled copper-tone fins provide depth to the building's facade and add interest Building 1 is a four-story office and research laboratory building that is through the interplay of light and shadow. All selected materials are designed to achieve LEED Gold and FitWel certification. The design of durable, resilient, natural and sustainable. Building 1 has been inspired by its location in the heart of the historic Arsenal on the Charles campus and its proximity to the rich natural The comprehensive design for Building 1 and accompanying site beauty of the Charles River Greenway. Building 1 borders the west improvements is informed by the formal design review completed facade of the existing six-story East Garage and faces the newly designed pursuant to Section 9.03(d) and is consistent with the standards identified greenspace at the center of the campus that will be improved as part of in the Watertown Design Guidelines and Arsenal Overlay Development the AOTC masterplan. District (AODD), specifically as related to the building scale, massing, setbacks, architectural expression and landscape design. Campus site Building 1 is informed by its surrounding context and consists of two improvements to the public realm beyond the limit of work line will be primary volumes. The first is a long, linear bar that shields the garage addressed in the Masterplan Special Permit Application package filed from view and is lifted from the ground plane to create a transparent, separately. activated facade at the base. This bar is clad with copper-tone, vertical sun shading fins that improve solar performance and mitigate evening light emanation from interior program spaces. Complementing the lifted Site Plan Review Statement ALEXAN DRIA. PAGE 188 3. Open Space: parking and dedicated spaces in the lower level of the East Parking Garage. The campus heart landscape will be publicly accessible and visible from Wooley Avenue and North Beacon Street. Access to the existing Emergency access to the site will be provided utilizing the existing street community path along the southern edge of the campus will be network, the shared streets and the combined bikeway and pedestrian maintained and the path will be resurfaced and new lighting added. As access along the west side of the West Parking Garage. Fire lanes in the open space is part of the broader Arsenal on the Charles campus the form of shared streets and paths surrounding Building 1 have been enhancements project, please refer to the master plan special permit provided. Off-street loading has been provided for in Building 1. amendment for campus-wide open space calculations. 5. Surface Water Drainage: 4. Circulation: The proposed surface water drainage system is designed to meet the The overall campus circulation system will be enhanced to maximize Massachusetts Department of Environmental Protection's (DEP's) convenience and safety of vehicular, bicycle, and pedestrian movement Stormwater Management Standards. With respect to the recharge within the Campus and in relation to adjacent streets. The internal streets requirements of Chapter 98: Stormwater Management and Erosion fronting and accessing Building 1 will be developed as "shared streets" to Control of the Town of Watertown's Code of Ordinances and the enhance the pedestrian experience while providing access and parking corresponding Rules and Regulations, given extensive environmental to the major elements of the campus buildings and open spaces. These limitations throughout the campus site, the stormwater management shared streets will be two-way or one-way and will be managed to system meets the infiltration design criteria to the best extent practicable. provide optimal circulation for times of day and events. The system has been designed to be implemented in phases as individual building sites are developed on the Campus. Internal vehicular circulation in the Building 1 area will be enhanced to improve the pedestrian experience and facilitate better access to the The Stormwater management system related to Building 1 builds upon adjacent East Parking Garage structure. Access to the East Parking Garage the overall Stormwater management strategy for the approved Campus will be from either Kingsbury Avenue, from the signalized Talcott Avenue Enhancement Plan. Runoff from paved areas subject to vehicular traffic entrance, or from Wooley Avenue -the two-way shared street south of will be pre-treated with either water quality structures, water quality building 311. Vehicles leaving the East garage will be directed to Talcott swales, rain gardens, and/or with bio-retention cells. Upon meeting the water quality treatment requirements, runoff will be directed to Avenue. a centralized subsurface, water-tight detention system located east of The on-site circulation will be an inclusive and accessible environment. Building 97. This portion of the proposed stormwater network ultimately Internal circulation will be ADA/ MAAB compliant. Parking for the retail discharges to an existing drainage system along North Beacon Street. component of the project and the other public elements of the site will There is a significant increase in landscaped areas as well as pervious be available to visitors during peak periods through managed on-street pavers throughout the Building 1 project area. Site Plan Review Statement Arsenal on the Charles I April 8, 2021 PAGE 189 The following stormwater design features of the stormwater management throughout the campus. The landscaped and pedestrian areas adjacent to strategy from the Campus Enhancement Plan are included in the surface proposed Building 1 feature pervious pavers that contribute to the overall water drainage system for Building 1. reduction in impervious areas by about 2.5% campus wide. Subsurface Detention Svstems Campus Enhancement Plan Phasing The Campus Enhancement Plan calls for the installation of three (3) new The Campus Enhancement Plan documented a complete stormwater subsurface detention systems as well as maintaining existing detention management system following full implementation of all project systems that would retain stormwater and gradually release runoff at phases. The Project's stormwater management system is designed to a controlled rate. All runoff associated with building roof and surface accommodate stormwater runoff from areas of the Campus included in drainage within the Building 1 project area will be collected, treated, and this Project phase. detained to control outlet volume leaving the site. 6. Utility Service: Water Qualitv Units The Campus Enhancement Plan describes the inclusion of water quality There is adequate capacity in existing utility infrastructure to service structures to capture stormwater runoff from all paved areas for vehicular the campus. All electric, telephone, cable TV and other communication use to provide treatment prior to detention/infiltration and subsequent distribution and service infrastructure will remain underground on the discharge to the municipal drain systems. Building 1 and its related site Campus Plan site. As individual building sites are developed, electric and improvements include eight (8) water quality units to treat stormwater communication duct banks, conduits, wires and cables will be evaluated runoff in the paved portions of the Project area prior to collection in the and repaired or replaced as required. subsurface detention system. Critical water and sanitary sewer distribution mains and related water/ Bio-retention Areas sewer utility services will be replaced at key locations throughout the As part of the campus-wide water quality treatment efforts, bio-retention campus as the site is revitalized. The existing water distribution system areas in the form of rain gardens, tree box filters, and bio-swales are at the Building 1 site has sufficient pressure and supply for the new included. Bio-retention is a treatment process in which contaminants proposed building. New water distribution infrastructure and valving is and sedimentation are removed from stormwater runoff through plant designed to improve flow for Building 1. Interconnection designed to media filtering prior to discharge. Surface drainage from paved areas for improve flow and provide better control of the water distribution system vehicular use will be directed to bio-retention areas for treatment prior in provided. Proposed sanitary sewer flow from Building 1 will be directed to detention/infiltration and subsequent discharge to municipal drainage to the North Beacon Street collection system. Based on a review of the systems. existing conditions survey, our estimates of the expected capacity of the existing municipal sewer system in North Beacon Street, and of the Pervious Pavers existing and projected sewage flows from the Campus Enhancement Plan, The Campus Enhancement Plan describes the expansion of pervious areas the existing sewer collection system in North Beacon Street has sufficient capacity to convey sewerage generated from Building 1. Site Plan Review Statement ALEXAN DRIA. PAGE 190 Electric Integrative Process: The existing infrastructure at or immediately adjacent to the Project Site The project team has been using an integrated process and opportunities based on current uses is believed to be adequate to support the Project. to achieve synergies across disciplines and building systems. Early energy The Project will be served from existing on-campus infrastructure. modeling efforts are underway and a water balance is being explored. The Electric service to the campus comes from underground feeds in both project anticipates one point for this credit. North Beacon Street and Arsenal Street. The provider for this utility is Eversource. Location and Transportation: Telecom/Data LEED credits in this category are awarded based on existing community Based on review of utility plans provided by Verizon and Comcast, infrastructure and services. In addition, LEED v4 added a significant it is VHBs understanding that both Verizon Fios and Comcast fiber amount of requirements to credits in this category. Because the project telecommunications and data services are available in the area. Service site is on a campus and in the heart of Watertown, several credits are will be drawn from existing on-campus infrastructure. available. 7. Environmental Sustainability: The project is adjacent to an existing garage and is on previously developed land, which will result in two points for the Sensitive Land The projects goal is to provide both an energy-conscious building and Protection credit. In addition, the project site is adjacent to a variety significant site improvements that address environmental sustainability of community amenities and has a Walkscore of 79, which will earn and conservation of resources. Making sustainable choices for the built the project three points for Surrounding Density and Diverse Uses. An environment requires the collaboration of all design disciplines in an additional two points will be achieved in the same credit rewarding the integrated process. To that end, the team has held sustainability-focus project for being sited in an area with relatively high FAR. meetings to define the project sustainability goals and outlining tasks and responsibilities going forward. Although there are bus stops on Arsenal Street, only Line 70 runs past these bus stops. This provides 86 weekday and 64 weekend trips, which is The projects will demonstrate compliance with the Section 7 sufficient to earn one point in the Access to Quality Transit credit. Under Environmental Sustainability criteria and the LEED Gold Certified the LEED v4.1 methodology, it may be possible for private shuttles to requirement using the LEED version 4 Core and Shell rating system. At further contribute, which may result in an additional point. this time, the project is tracking 64 points as "Yes" with an additional 10 "Likely" points, therefore exceeding the required 60-point Gold threshold. The project is adjacent to an existing bike network, including bike lanes on Please see the included scorecard. Arsenal Street and the Watertown Greenway. The project is also providing interior bike storage and showers and will therefore earn one point under Below is a section-by-section breakdown detailing the project's approach: the Bicycle Facilities credit. Demonstrating compliance with the Reduced Parking Footprint and Green Site Plan Review Statement Arsenal on the Charles I April 8, 2021 PAGE 191 Vehicles credits can prove challenging on campus settings due to the The project plans on earning one point for the Light Pollution Reduction nature of shared parking which means that all campus parking should be credit through selection of dark sky compliant fixtures and care in location included. The campus is anticipating 2,812 parking spaces this is in excess of site lighting. In addition, the project will provide a Tenant Design and of the threshold for the Reduced Parking credit. The project is evaluating Construction document to prospective tenants, which will earn one point the feasibility of earning the LEED Green Vehicles credit through either for this credit. a single building or campus approach by and is holding the credit as "Maybe." Water Efficiencv: A high level of water savings is anticipated using low flow aerators on Sustainable Sites: sinks, low flow toilets and urinals, and low flow showerheads. Depending The project team has spent significant time reviewing existing site on final occupancy, these fixtures in combination will result in 40% water conditions in relation to topography, hydrology, climate, vegetation, savings, earning the project 4 points. Water Sense Labeled fixtures will be soils, human use, and human health and will earn one point for the Site specified where eligible, as LEED v4 requires this. Assessment credit. Significant water metering will be planned, including water used for The campus has significant green space with pedestrian amenities, which cooling tower, irrigation and domestic hot water. One point is available if will be enhanced through the development process, meeting the intent two of these systems are separately metered under the Water Metering for the Open Space credit with approximately 50% of the site area being credit. assumed for the LEED project boundary counting towards compliance. This open space includes significant native plantings, and the team is Wherever possible, native and adapted plantings that require limited anticipating also earning Site Development-Protect and Restore Habitat irrigation are being used. This will allow the project to earn one point in under a LEED v4.1 methodology, which will include a small pollinator the Outdoor Water Use Reduction credit. One additional point for the garden. Cooling Tower credit will be earned for testing water and maximizing the number of cycles allowable. The site is adjacent to an existing parking garage, and as a result, one point for the Heat Island Reduction credit is anticipated for providing Enerev and Atmosphere: parking in a structure. Light colored roofing and hardscaping is also The project is evaluating HVAC systems and looking to include planned, which may make an additional point available, pending final photovoltaics (PV) on the adjacent garage roof to support aggressive color selections. energy goals. The early phase energy models is showing an energy savings of approximately 17%, the project is currently holding 8 points in "Yes" Due to somewhat limited site disturbance related to development on for Optimize Energy Performance. The team is still evaluating a series an existing campus, neither the Rainwater Management is not being of Energy Conservation measures (see energy model) which will increase targeted. the energy performance of the building, and these points are being held as "More Likely" and "Less Likely." The PV system could support the Site Plan Review Statement ALEXAN DRIA. PAGE 1 92 achievement of all points in the Optimize Energy Performance Credit and becoming available as more EPDs, HPDs, and CSRs are developed. The also allow three points to be earned in the Renewable Energy Production project will target a minimum of 20 EPDs and 20 HPDs in addition to Credit depending upon the structure of the system's purchase and sourcing materials with sustainability attributes (i.e. recycled content, FSC allocation (or purchase) of Renewable Energy Credits to offset renewable wood, rapidly renewable material, C2C certification). This will allow the production allocated to the building. project to earn one point in each of the following Building Discloser and Optimization credits: Environmental Product Declarations, Sourcing of Building commissioning helps ensure that the building meets set Raw Materials, and Material Ingredients. performance goals. LEED v4 offers credits for both building system and envelope commissioning, and enhanced and monitoring-based A whole building life cycle assessment provides the team an commissioning are planned for the project. Envelope commissioning is understanding of the environmental impact of the project construction. also planned. This study will be conducted and will earn the project three points for the Life-Cycle Impact Reduction credit. In addition, the project will target The project will install meters for future tenant spaces so that tenants will Construction Waste Recycling with 75% diversion, including three waste be capable of independently metering energy consumption (electricity, streams, to earn two points in this credit. chilled water, etc.) for all systems dedicated to their space. This will earn one point in the Advanced Energy Metering credit. Indoor Environmental Qualitv: Alexandra Real Estate offsets its energy use with Green Power purchases, The Enhanced IAQ Strategies credit will be targeted with a focus on and therefore the project is anticipating two points in the Green Power filtration, walk off mats, exhausting chemical storage rooms. This will earn and Carbon Offsets credit for purchasing RECs and carbon offsets for the project one point, and a second is being held as "Maybe" and will 100% of the energy use for 5 years. continue to be evaluated. In addition, the Construction IAQ Management Plan credit will be targeted, and the specifications will require the It is assumed that environmentally friendly refrigerants will be used, so construction team to develop and implement a plan. credits for both fundamental and enhanced refrigerant management are anticipated. The Demand Control can be challenging for Core and Shell Care in material selection is critical for optimizing credits in this category. projects, as it requires significant load shedding; however, under LEED Unlike LEED 2009, v4.0 & v4.1 looks at emissions of materials, beyond v4.1 there may be an option for compliance, so the credits are being held VOCs. LEED v4.1 provides opportunities for teams to earn more credits as "Less Likely." than were available in LEED v4.0, and this path will be pursued. The project will target paints and coatings, composite wood, flooring, ceilings, Materials and Resources: and insulation for these credits, and anticipates earning all three points in One of the most significant changes in LEED v4 is in the Materials and the Low-Emitting Materials credit. Resources section. The focus has changed from materials themselves to material transparency. Manufacturers are quickly adapting to this The floorplate of the project and its connection to the parking garage change, with more of the information required to earn these credits makes achievement of the Daylight and Views credits unlikely, and Site Plan Review Statement Arsenal on the Charles I April 8, 2021 PAGE 193 therefore they are not being targeted. equipment will be screened through a combination of landscape elements (trees and shrubs) and fixed screen walls or fences. Innovation: The project anticipates earning all credits in the Innovation and Design As with most lab buildings, Building 1 requires a robust loading and Category. These credits will be selected to help the project tell the story receiving area to accommodate equipment and material for the lab that the client is most excited about. Although these credits have yet to tenants. For Building 1, the loading dock is located to the south of the be selected, they may include the following: East Garage and accessed from the building via an internal corridor • Walkable Project Site through the garage. The loading dock will be accessed by vehicles from a • Designing for Nature driveway connecting to Kingsbury Avenue. To mitigate the visibility of the • Design for Active Occupants loading dock, it has been recessed into the landscape by 4 feet and will be • Green Building Education shielded from view with both an architectural screen wall and a heavily • O+M Starter Kit landscaped buffer. • Integrated Analysis of Building Material • WELL Credits 9. Safety: • Fitwel Credits • Occupant Survey The campus is accessible by emergency vehicles from Arsenal Street via Kingsbury and Talcott Avenues as well as from North Beacon Street via Regional Prioritv: School Street. Fire truck access is around the perimeter of the building The following credits are regional priorities. Additional points are as indicated in the Fire Truck Maneuvering figure attached. The building available for these credits if they are earned at the listed thresholds: has two separate egress stairs. One stair exits directly from the building, • Rainwater Management (3 points) the other exits through the lobby. Both exits lead to an easily identifiable • Optimize Energy Performance (8 points) open space away from the building. • Building Life Cycle Impact Reduction (3 points) • Indoor Water Use Reduction (3 points) 10. Design: • Renewable Energy Production (2 points) • High Priority Sites (2 points) The Project will be designed to protect abutting properties from detrimental site characteristics resulting from the proposed use by 8. Screening: implementing a stormwater management system which will reduce stormwater runoff and water pollutants. Construction related impacts, Rooftop equipment and enclosed penthouse are shielded from such as dust and erosion, will be mitigated through the implementation of public view by a perforated metal screen. The screen color and finish a construction period Stormwater Pollution Prevention Plan (SWPPP). complements the building facade and is designed to be compatible with Efforts were taken to mitigate the building's impact on surrounding the aesthetic and material language of the building. Ground mounted- neighborhoods, including breaking down the building's mass by Site Plan Review Statement ALEXANDRIA, PAGE 194 organizing it into two primary sections and by following the 50-foot zoning setback to preserve the riparian corridor along North Beacon Street and the river's edge. Furthermore, the vertical fins on the building's primary facade will mitigate evening light emanation from interior program spaces. The site lighting system will be designed to avoid visual impacts to the abutters in compliance with the zoning requirements and Dark Sky Initiative. Mechanical systems will be high efficiency designed to operate at 90-95% efficiency and to minimize noise levels. Acoustical engineering services have begun and will be continued throughout the design process. Evaluation of the rooftop and ground noise producing equipment will be conducted. Equipment that exceeds comfortable noise levels for the adjacent residential properties will be properly screened and buffered with acoustical barriers. See Renderings showing the new building in the surrounding context for reference. Site Plan Review Statement Arsenal on the Charles I April 8, 2021 PAGE 195 Building Massing & Setbacks 1 REFERENCING SCALE The scale of Building 1 references its adjacencies. The linear bar is a nod to the long facade of 311 Arsenal Street and length of the building closely aligns to that of the East Garage. 2 VERTICAL ELEMENTS In order to break up the primary horizontal 0 ...,- building facade, a wrapping frame folds to the ground and carves away the main _ volume of the building to define the lobby entrance. ' 3 MASSING VARIATION -�--iIbl� _ �� � In order to break down the overall massing _ g of the building it is broken into two distinct ID volumes, each with its own facade treatment. The lower, angled volume is parallel to the footprint of 400 North Beacon. Together, the buildings define the perimeter of the central lawn and frame the view to the Charles River. 4 SETBACKS The building form follows the 50 foot setback to preserve the riparian corridor along North Beacon Street and the river's edge. The setback maintains the existing pedestrian and bike trail at the edge of the campus and allows for continued permeability of the site to the community. The existing pathway will be revitalized with landscaping, trail-markers, and appropriate illumination for safety. AODD Design Guidelines Overview ALEXANDRIA. PAGE 196 Building Height 1 RANGE OF HEIGHTS/ UPPER STORY SETBACKS In order to respect campus surroundings, the overall scale of the building has been broken down by differing the heights of its two main volumes. Furthermore, the stepback above the angular volume diminishes the building's apparent height and breaks down its scale facing the Event Lawn. 2 REFERENCES TO CONTEXT Rr: Two key elements of the building x ' reference its historic surroundings. First, }� © the long, linear form of the primary building volume provides a counterpoint r tY to the long, repetitive facade of 311 Arsenal Street. Second, the lower volume matches the angled footprint of 400 North Beacon Street to define the perimeter of �`` � ��a , the Event Lawn and frame the view to the _ F �+ Charles River. �a • �� f .� i �. it ) F �i£�W,C.{. II � �4 Rq� YC 3 MECHANICAL PENTHOUSE `^ Rooftop mechanical equipment and enclosed penthouse are shielded from public view by a perforated metal screen. The screen color and finish complements the building facade and designed to be compatible with the aesthetic and material language of the building. 4 GROUND FLOOR OVERHANG The recessed ground floor facade protects pedestrians from the elements, reduces solar gain, and delineates the base of the building from the upper stories. AODD Design Guidelines Overview Arsenal on the Charles I April 8, 2021 PAGE 197 Facade Treatment & Materials 1 HIGH QUALITY AND NATURAL MATERIALS The material palate for Building 1 draws inspiration from the Arsenal on the Charles site. The angled copper-tone fins reference the site's rich history of industry and metallurgy. The blackened steel frame, wood soffit and stacked linear brick are a modern reference to rr _ the existing vernacular architecture on site. A high-performance curtainwall 0 © _r� system maximizes the building's energy �rr�rrrri performance.All selected materials are r� durable, resilient, natural and sustainable. — ; 2 TEXTURE, VARIATION,AND TACTILITY Differing facade treatments emphasize ' = the two primary volumes of Building 1 >-` and generates a balanced composition. Selected natural materials such as wood and stacked masonry celebrate variations in tone and texture. The angled copper- .. _ t + �,.,h.a,®..;-•�''ik„ tE l , r -, �• '� �' ` ` - - tone fins introduce depth into the building's facade and adds interest through the - -- ` ' interplay of light and shadow. 3 TERRACES The introduction of a fourth floor terrace provides the opportunity for exterior greenspace and fosters a healthy work environment by celebrating the concept of biophilia. AODD Design Guidelines Overview ALEXAN DR IA. PAGE 198 v10 G . _ 1 A4 Milo Chapter Building 2 Project Narrative Supporting Site Plan Review Approval of Phase 2 of the Campus Master Plan 3 t $. � ri N Approval Summary Chapter Contents The Petitioner, Alexandria Real Estate Equities, Inc., requests a Final Site • Enlarged Site Plan Plan Review for Phase 2. Phase 2 will comprise of Building 1 and Building • Zoning Summary 2, new four-story office and research laboratory buildings and related • Architectural Precedent Images site enhancements. Narrative information supporting the Final Site Plan • Renderings Review Approval for Building 2 is located in this chapter. • Special Permit Supporting Statement • Site Plan Review Statement Building 2 is a four-story office and research laboratory building located • AODD Design Guideline Summary in the eastern half of the Arsenal on the Charles campus. The building will be designed to achieve LEED Gold and FitWel certification. ALEXAN DRIA. PAGE 1 102 z 321 ARSENAL > 200TALCOTT Q z O z O .» KINGSBURY AVENUE S � 1 KINGSBURY 400TALCOTT :r 2 KINGSBURY Arsenal on the Charles April 8, 2021 PAGE1103 -41 ARSENAL STREET + ' I t r '----_ _���.-,�•�+ .....25'SIDE SETBACK r AT ARSENAL STREET - - } .r 25'SIDE SETBACK•-••••... _ ��...ti�..� 25'OR 45 DEGREE PLANE•-=-•- NORTy FROM EDGE OF STREET BEACO T _! 74► Ike E _, .. _ ,_, -,yam .� sJ �: - ;. - R• ' - I • � � «,s.r •.. dam � wd,. �•-••...25'SIDE SETBACK 50'SETBACK EAST OF . "T ❑ ■ } CHARLES RIVER ROAD Zoning Setbacks Plan ALEXANDRIA. PAGE 1 104 w� s//0% 000 0- // 0001011110 00�,/ 0 \\ �bN* 00 ' ti 24'-0" I� 24'0" 24'-0- , e 24'-0" M \ I� Rio 24'-0„ Il�l la � Al 11 lv AA _AA- 11 1J AAA A A 1la 1 Ip AI AA AA A 1111 11_.-1 A A .A AA AA 11 A 11 A�A 1 AA, 11 AA Building Height Analysis Arsenal on the Charles I April 8, 2021 PAGE 1 105 11-1 rry imo _ � r fA do 4{}r 7{ open qnr r^ re A4T 4 d?q � i�fll r i F I -= '-op-q � ! Architectural Precedent Images A L E X A N DRIA. PAGE1106 r� L 1s ■ f N � 2 J I �IDID slim r *,. "`;',' + I��II III —�s...i�tl� ii •�i�o�� g. � � :� � �i �s � � r - . East 321 Arsenal Garage 200 Ta Icott 1/ + a n Kingsbury ' o DroP-Off,Court .. fie Retaining Wall "'P"e PCB Building 2 Screen surrou� Dro Off Loading r �` I �41 oadingl rea 1 Kingsbury " Transformers t. 400 Talcott Lawn and Park Space r 117M. or y _ x • - - - - - - - ;. / J Bright Horizons Playground r Y r' Enlarged Illustrative Plan ALEXANDRIA. PAGE1108 r�- ram' ' '. :..�.�;4... w -• � 1 .fF: �- Ni IaA �. �I � ��K R 'i l'�� �;�,• Yl�a"i°'.s Y. �'9•�. b'�. 4 f 'S` -F 1{y R ,,7� yam. _ v • f t �■ w° � � t _ 'ro Sf���+'a4,{ 'w _ ; f,4'Y'a LL 7.1 } s, r j � ..I .�`•. � : t Retaining all at Building Blue Bike A Arsenal Street Station j4 77' a s a Shuttle Stop ,Asenal Green Building 43 �I 311 Arsenal _; r 4 Wooley Avenue 71 M Mosesian osesian • ' II Center for Drop-Offs the Arts t Improved T ',' East cafe terrace ' , 4k Garage . v Talcott o Connector aw � D rr 1 v Tf Reconfigured , Garage 321 Entrance/Exit Arsenal "" Dog Rellet Area Load i r Dock Fe . ( 200 Talcott "•�` `' r- nchlin O A L E X A N DRIA. PAGE I110 Special Permit Supporting Statement I Per Section 9.05(B) of the town of Watertown Zoning Ordinance 1. Is the subject site an appropriate location for such use, structure, and/ 2. Will the proposed use/structures adversely affect the neighborhood? or condition? YES/NO. Explain. YES/NO. Explain. YES. NO. The Building 2 site is located in the eastern half of the Arsenal on The placement of the building was carefully considered and designed the Charles campus. Building 2 is part of an extensive campus-wide to minimize impacts to the adjacent neighborhood, integrate into the masterplan that will redevelop it into a collaborative and innovative historic fabric of the campus and respect the site's topography. Building 2 campus including life science, office, retail, and community uses, as well is located toward the interior of the campus and will have limited visibility as publicly accessible open spaces and streetscape improvements. The from surrounding neighborhoods. Where the building is visible from proposed building is consistent in use with several nearby office and the campus exterior, mitigation measures will be implemented. These research + development buildings that have contributed to a significant include vegetative screening along Talcott Avenue and landscape buffers lab/ R&D cluster along Arsenal Street. to reduce building visibility from adjacent neighborhoods. Building 2 and associated landscape improvements (the "Project") have been designed to integrate into historic fabric of the campus and form a The site lighting system will be designed to avoid visual impacts to the series of defined public spaces at its periphery that will be improved as abutters in compliance with the zoning requirements and Dark Sky part of the AOTC campus masterplan. The building's proposed height and Initiative. Mechanical systems will be high efficiency designed to operate setbacks comply with zoning and Arsenal Overlay Development District at 90-95% efficiency and to minimize noise levels. Acoustical engineering (AODD) design guidelines. Its massing 2 is a linear form that echoes the services have begun and will be continued throughout the design process. footprints of the existing industrial buildings on the campus. Evaluation of the rooftop and ground noise producing equipment will be conducted. Equipment that exceeds comfortable noise levels for the The materiality and facade expression of Building 2 draw inspiration from adjacent residential properties will be properly screened and buffered the Arsenal on the Charles campus through the integration of contextual with acoustical barriers. materials and industrial accents. The facade blends the organization and repetition found on the masonry facades of the campus with modern The Project will be designed to protect abutting properties from glass and metal materials. The expressed C-Channel frame organizes detrimental site characteristics resulting from the proposed use by the facade into bays and articulated facade elements give it a sense of implementing a stormwater management system which will reduce depth. The overall design expression of Building 2 is consistent with the stormwater runoff and water pollutants. Construction related impacts, standards identified in the Watertown Design Guidelines and Arsenal such as dust and erosion, will be mitigated through the implementation of Overlay Development District (AODD), and will positively contribute to a construction period Stormwater Pollution Prevention Plan (SWPPP). the architectural evolution of the Arsenal on the Charles campus. Special Permit Supporting Statement Arsenal on the Charles I April 8, 2021 PAGE 1111 3. Is there potential for nuisance or serious hazards to vehicle or 4. Will adequate and appropriate facilities be provided for the proper pedestrians? YES/NO. Explain. operation of the proposed use? YES/NO. Explain. NO. YES. As part of the masterplan, the campus circulation system will be The proposed development will be designed in accordance with the enhanced to maximize convenience and safety of vehicular, bicycle, and Massachusetts State Building Code, the Americans with Disabilities pedestrian movement within the campus and in relation to adjacent Act (ADA), Massachusetts Architectural Access Board (MAAB) and all streets and path connections. The proposed masterplan prioritizes the other relevant governing requirements. Additionally, the Project will flow and interaction of pedestrians and cyclists over motorized vehicles be designed to comply with the requirements of the Stretch Energy within the campus. The four main vehicular access points to the campus Code and will be certifiable with the USGBC for a LEED Gold rating. The will be maintained; however, the internal vehicular circulation will be attached LEED V4 scorecard describes the pathway to certification. enhanced to improve the pedestrian experience and facilitate better The proposed campus stormwater management system is designed to access to the retail and structured parking components. meet the Massachusetts Department of Environmental Protection's (DEP's) Stormwater Management Standards. With respect to the The proposed uses of Building 2 will reduce overall parking demand, recharge requirements of Chapter 98: Stormwater Management and allow for the reduction of parking from the previously approved plan Erosion Control of the Town of Watertown's Code of Ordinances and and enable the creation of a more pedestrian friendly, green campus. the corresponding Rules and Regulations, the proposed stormwater For enhanced safety, loading has been situated off-street and away from management system has been designed to the best extent practicable. primary pedestrian corridors and building entries. The on-site circulation Off site mitigation, including drainage improvements at the Commander's will create an inclusive and accessible environment. All primary building Mansion and within Talcott Avenue, has been reviewed and coordinated access and internal site circulation will be ADA/MAAB compliant. with the Town. The system has been designed to be implemented in phases as individual building sites are developed on the Campus. Special Permit Supporting Statement ALEXAN DR IA. PAGE 1 112 Site Plan Review Statement I Per Section 9.03(C) of the town of Watertown Zoning Ordinance 1. Landscape: The loading dock is located along the east facade of Building 2 and The landscape associated with Building 2 (together, the "Project") is part accommodates three WB-40 tractor trailers, which approach the dock of the broader Arsenal on the Charles ("AOTC") campus enhancements from Kingsbury Avenue. The driveway to the loading dock slopes down project, which employs a consistent language of granite planters, seating four feet from Kingsbury Avenue to allow trucks to align with the desired elements, unit pavements, and robust plantings which unify the campus loading dock elevation. New transformers associated with building 2 are landscape, and offer human scale areas for gathering and enjoying the located within the loading area, as is a trash compactor. Retaining walls outdoor public realm of the campus. separate the loading area from the adjacent landscape, and 42" high screen walls on top of the retaining walls provide fall protection and Kingsbury Avenue Realignment visual screening along the edges of the loading drive. Shrub planting To accommodate Building 2, the east-west segment of Kingsbury Avenue further screens the loading area from the park landscape and streetscape. is realigned to the north of its current location. The new streetscape along this east-west segment of Kingsbury Avenue includes a six foot wide New pathways maintain connections to existing entrances of the 400 tree lawn, new columnar street trees, and a six foot wide sidewalk. A Talcott building, including the ADA ramps along the west and north landscape buffer is provided between the sidewalk and the north facade facades of building 2. New light poles integrated into the streetscape provide appropriate illumination levels for both vehicles and pedestrians. The River Gardens and Bright Horizons Plavground planted central island at the intersection with Talcott Avenue is reshaped Immediately south of Building 2, new tree plantings provide passive solar to accommodate the turning radii of delivery vehicles accessing the shading to the south building facade. Further south of Building 2, a new campus' life science facilities. New evergreen shrub plantings along the park landscape with open lawns and informal groupings of trees and eastern edge of Talcott Avenue opposite from the new loading dock shrubs adds to the open space on campus. The existing Bright Horizons between 100 and 200 Talcott prevent headlights from reaching the playground associated with the daycare facility within 400 Talcott condominium windows across the campus property line. Avenue, currently located just west of 400 Talcott, is relocated south of 3 Kingsbury to allow for a more publicly accessible landscape just south Kingsbury DroD-Off Court and Building 2 landscape of Building 2. The existing surface parking lot south of 1 Kingsbury is The main entry to Building 2 is located on the west facade, facing a new also replaced with a park-like landscape of lawn, trees, and shrubs. The vehicular arrival court and generously sized entry plaza, complete with shuttles currently parked in this location will be stored at an off-site ARE concrete unit paving, trees and planted areas, and space for movable property. The existing loading area south of 1 Kingsbury is relocated west tables and chairs. The arrival court accommodates the campus shuttle, of the building adjacent to the screened loading area for building 1 south as well as rideshare and personal vehicle drop-off, and has a bioretention of the East Garage. The building's transformers and utility appurtenances area at the center of the turnaround. The arrival court also provides a will remain south of the building and will be enclosed by a screen wall new address for the 1 Kingsbury Avenue building, whose front door opens and buffered with shrub and tree planting. onto the plaza. Site Plan Review Statement Arsenal on the Charles I April 8, 2021 PAGE 1 113 The stonedust path that runs along the southern edge of the campus is is positioned amongst a collection of historic masonry buildings with maintained and enhanced with new plantings and LED site lighting. varying scales and orientations. The design of Building 2 weaves together the historic fabric of the campus and forms a series of defined public Kinesbury Avenue and the Arsenal Green spaces at its periphery that will be improved as part of the AOTC campus The north-south segment of Kingsbury Avenue is realigned to connect masterplan. to the new arrival court west of Building 2. The intersection with Arsenal Street remains right-turn-in-only, and at its current width. Within the Building 2 is a linear form that echoes the footprints of the existing campus,just south of the Arsenal intersection, the curb of Kingsbury industrial buildings on the campus. Its massing is a singular design Avenue is altered to accommodate the turning movements of large gesture, with a volume that is elevated from the ground plane to form a delivery vehicles serving the campus' life science facilities. A pull off recessed base. At the building's western edge, the upper volume lifts to lane along the east facade of Building 311, on the west side of Kingsbury form a double-height lobby wrapped in transparent glass that faces the Avenue, accommodates the campus shuttle, as well as rideshare and new Kingsbury Avenue arrival court that is envisioned as part of the AOTC personal vehicle drop-off, including for special events at the Mosesian campus masterplan. The scale of the lobby references the height of the Center. An expanded drop-off along Thornton Avenue, east of the adjacent buildings and provides visibility from the arrival court to the Mosesian Center, provides a second location for drop-off and valet south lawn. parking for special events at the Theater. The existing double row of sweetgum trees framing the Arsenal Green are protected and preserved The materiality and facade expression of Building 2 draw inspiration from on all three sides, with the exception of the two southernmost trees in the Arsenal on the Charles campus through the integration of contextual the western allee, which are removed to allow new utility connections, materials and industrial accents. The facade blends the organization and including stormwater piping, to the new stormwater chambers to be repetition found on the masonry facades of the campus with modern buried below the Arsenal Green. glass and metal materials. The expressed C-Channel frame organizes the facade into bays and articulated facade elements give it a sense of depth. The existing double row of trees west of Kingsbury Avenue along the East The wood soffits and masonry provide warmth to the building's base and Garage are protected and preserved. The landscape east of Kingsbury compliments the materiality of adjacent structures. A high-performance Avenue is enhanced with a new bioretention area and tree plantings. curtainwall system maximizes the building's energy performance. All Landscape features surrounding the Branchline restaurant are protected selected materials are durable, resilient, natural and sustainable. and maintained. The comprehensive design for Building 2 and accompanying site 2. Relation of Buildings to Environment: improvements is informed by the formal design review completed pursuant to Section 9.03(d) and is consistent with the standards identified Building 2 is a four-story office and research laboratory building that in the Watertown Design Guidelines and Arsenal Overlay Development is designed to achieve LEED Gold and FitWel certification. Building 2 District (AODD), specifically as related to the building scale, massing, anchors the eastern side of the Arsenal on the Charles campus and setbacks, architectural expression and landscape design. Campus site Site Plan Review Statement ALEXAN DRIA. PAGE 1 114 improvements to the public realm beyond the limit of work line will be large open plaza space. addressed in the Masterplan Special Permit Application package filed separately. The on-site circulation will be an inclusive and accessible environment. Internal circulation will be ADA/ MAAB compliant. Parking for the retail 3. Open Space: component of the project and the other public elements of the site will be available to visitors during peak periods through managed on-street The landscape associated with this project is publicly accessible and parking and dedicated spaces in the lower level of the East Parking visible from Kingsbury Avenue and the path that runs along the southern Garage. edge of the campus that is frequently used by community members. This open space is part of the broader Arsenal on the Charles campus Emergency access to the site will be provided utilizing the existing street enhancements project; please refer to the master plan special permit network including Kingsbury Avenue, Talcott Avenue and School Street. amendment for campus-wide open space calculations. Fire lanes in the form of streets and paths surrounding Building 2 have been provided. Off-street loading has been provided for Building 2. 4. Circulation: S. Surface Water Drainage: The overall campus circulation system will be enhanced to maximize convenience and safety of vehicular, bicycle, and pedestrian movement The proposed surface water drainage system is designed to meet the within the Campus and in relation to adjacent streets. The internal streets Massachusetts Department of Environmental Protection's (DEP's) fronting and accessing Building 2 will be developed as "shared streets" to Stormwater Management Standards. With respect to the recharge enhance the pedestrian experience while providing access and parking to requirements of Chapter 98: Stormwater Management and Erosion the major elements of the campus buildings and open spaces. Kingsbury Control of the Town of Watertown's Code of Ordinances and the Avenue will be relocated southerly from the vicinity of the East Parking corresponding Rules and Regulations, given extensive environmental Garage entrance driveway to a new location at its intersection with Talcott limitations throughout the campus site, the stormwater management Avenue. The two-way portion of the street will be managed to provide system meets the infiltration design criteria to the best extent practicable. optimal circulation for times of day and events. The system has been designed to be implemented in phases as individual building sites are developed on the Campus. Internal vehicular circulation in the Building 2 area will be enhanced to improve the pedestrian experience and facilitate better access to the The stormwater management system related to Building 2 builds upon adjacent East Parking Garage structure. Access to the East Parking Garage the overall stormwater management strategy for the approved Campus will be from either a one-way entrance from Kingsbury Avenue, from the Enhancement Plan. Runoff from paved areas subject to vehicular traffic signalized Talcott Avenue entrance, or from Wooley Avenue. Vehicles will be pre-treated with either water quality structures, water quality leaving the East garage will be directed to exit the site at Talcott Avenue. swales, rain gardens, and/or with bio-retention cells. Upon meeting An expanded drop off area is proposed west of Building 2 supported by a the water quality treatment requirements, runoff will be directed to Site Plan Review Statement Arsenal on the Charles I April 8, 2021 PAGE1115 centralized subsurface infiltration systems located just south of Building media filtering prior to discharge. Surface drainage from paved areas for 2, south of Building 37, and north of Building 43. This portion of the vehicular use will be directed to bio-retention areas for treatment prior proposed stormwater network ultimately discharges to an existing to detention/infiltration and subsequent discharge to municipal drainage drainage system along North Beacon Street. There is a significant increase systems. in landscaped areas as well as pervious pavers throughout the Building 2 Pervious Pavers project area. The Campus Enhancement Plan describes the expansion of pervious areas throughout the campus. The landscaped and pedestrian areas adjacent to The following stormwater design features of the stormwater management proposed Building 2 feature pervious pavers that contribute to the overall strategy from the Campus Enhancement Plan are included in the surface reduction in impervious areas by about 2.5% campus wide. water drainage system for Building 2 Campus Enhancement Plan Phasine Subsurface Infiltration Svstems The Campus Enhancement Plan documented a complete stormwater The Campus Enhancement Plan calls for the installation of six (6) new management system following full implementation of all project subsurface infiltration systems that provide groundwater recharge for the phases. The Project's stormwater management system is designed to campus site. Three (3) of those systems are located within the Building 2 accommodate stormwater runoff from areas of the Campus included in Project area. All runoff associated with building roof and surface drainage this Project phase. within the Project area will be collected, treated and detained/infiltrated to provide groundwater recharge and control outlet volume leaving the 6. Utility Service: site. There is adequate capacity in existing utility infrastructure to service Water Qualitv Units the campus. All electric, telephone, cable TV and other communication The Campus Enhancement Plan describes the inclusion of water quality distribution and service infrastructure will remain underground on the structures to capture stormwater runoff from all paved areas for vehicular Campus Plan site. As individual building sites are developed, electric and use to provide treatment prior to detention/infiltration and subsequent communication duct banks, conduits, wires and cables will be evaluated discharge to the municipal drain systems. Building 2 and its related site and repaired or replaced as required. improvements include nine (9) water quality units to treat stormwater runoff in the paved portions of the Project area prior to collection in the Critical water and sanitary sewer distribution mains and related water/ subsurface detention system. sewer utility services will be replaced at key locations throughout the campus as the site is revitalized. The existing water distribution system Bio-retention Areas at the Building 2 site has sufficient supply for the new proposed building. As part of the campus-wide water quality treatment efforts, bio-retention New water distribution infrastructure and valving is designed to improve areas in the form of rain gardens, tree box filters, and bio-swales are flow for Building 2. Interconnection designed to provide better control of included. Bio-retention is a treatment process in which contaminants the water distribution system is provided. Proposed sanitary sewer flow and sedimentation are removed from stormwater runoff through plant Site Plan Review Statement ALEXAN DRIA. PAGE 1 116 from Building 2 will be directed to the North Beacon Street collection The projects will demonstrate compliance with the Section 7 system. Based on a review of the existing conditions survey, our estimates Environmental Sustainability criteria and the LEED Gold Certified of the expected capacity of the existing municipal sewer system in North requirement using the LEED version 4 Core and Shell rating system. At Beacon Street, and of the existing and projected sewage flows from the this time, the project is tracking 65 points as "Yes" with an additional Campus Enhancement Plan, the existing sewer collection system in North 6"Maybe" points, therefore exceeding the required 60-point Gold Beacon Street has sufficient capacity to convey sewerage generated from threshold. Please see the included scorecard. Building 2. Below is a section-by-section breakdown detailing the project's approach: Electric The existing infrastructure at or immediately adjacent to the Project Site Integrative Process: based on current uses is believed to be adequate to support the Project. The project team has been using an integrated process and opportunities The Project will be served from existing on-campus infrastructure. to achieve synergies across disciplines and building systems. Early energy Electric service to the campus comes from underground feeds in both modeling efforts are underway and a water balance is being explored. The North Beacon Street and Arsenal Street. The provider for this utility is project anticipates one point for this credit. Eversource. Location and Transportation: Telecom/Data LEED credits in this category are awarded based on existing community Based on review of utility plans provided by Verizon and Comcast, infrastructure and services. In addition, LEED v4 added a significant it is VHBs understanding that both Verizon Fios and Comcast fiber amount of requirements to credits in this category. Because the project telecommunications and data services are available in the area. Service site is on a campus and in the heart of Watertown, several credits are will be drawn from existing on-campus infrastructure. available. 7. Environmental Sustainability: The project is on a previously developed site, which will result in two points for the Sensitive Land Protection credit. In addition, the project site The projects goal is to provide both an energy-conscious building and is adjacent to a variety of community amenities and has a Walkscore of significant site improvements that address environmental sustainability 79, which will earn the project three points for Surrounding Density and and conservation of resources. Making sustainable choices for the built Diverse Uses. An additional two points will be achieved in the same credit environment requires the collaboration of all design disciplines in an rewarding the project for being sited in an area with relatively high FAR. integrated process. To that end, the team has held sustainability-focus meetings to define the project sustainability goals and outlining tasks and Although there are bus stops on Arsenal Street, only Line 70 runs past responsibilities going forward. these bus stops. This provides 86 weekday and 64 weekend trips, which is sufficient to earn one point in the Access to Quality Transit credit. Under the LEED v4.1 methodology, it may be possible for private shuttles to Site Plan Review Statement Arsenal on the Charles I April 8, 2021 PAGE 1 117 further contribute, which may result in an additional point. points for the Heat Island Reduction credit. The project is adjacent to an existing bike network, including bike lanes on Due to somewhat limited site disturbance related to development on Arsenal Street and the Watertown Greenway. The project is also providing an existing campus, neither the Rainwater Management is not being interior bike storage and showers and will therefore earn one point under targeted. the Bicycle Facilities credit. The project plans on earning one point for the Light Pollution Reduction Demonstrating compliance with the Reduced Parking Footprint and Green credit through selection of dark sky compliant fixtures and care in location Vehicles credits can prove challenging on campus settings due to the of site lighting. In addition, the project will provide a Tenant Design and nature of shared parking which means that all campus parking should be Construction document to prospective tenants, which will earn one point included. The campus is anticipating 2,812 parking spaces this is in excess for this credit. of the threshold for the Reduced Parking credit. The project is evaluating the feasibility of earning the LEED Green Vehicles credit through either Water Efficiencv: a single building or campus approach by and is holding the credit as A high level of water savings is anticipated using low flow aerators on "Maybe." sinks, low flow toilets and urinals, and low flow showerheads. Depending on final occupancy, these fixtures in combination will result in 40% water Sustainable Sites: savings, earning the project 4 points. Water Sense Labeled fixtures will be The project team has spent significant time reviewing existing site specified where eligible, as LEED v4 requires this. conditions in relation to topography, hydrology, climate, vegetation, soils, human use, and human health and will earn one point for the Site Significant water metering will be planned, including water used for Assessment credit. cooling tower, irrigation and domestic hot water. One point is available if two of these systems are separately metered under the Water Metering The campus has significant green space with pedestrian amenities, which credit. will be enhanced through the development process, meeting the intent for the Open Space credit with approximately 35% of the site area being Wherever possible, native and adapted plantings that require limited assumed for the LEED project boundary counting towards compliance. irrigation are being used. This will allow the project to earn one point in This open space includes significant native plantings, and the team is the Outdoor Water Use Reduction credit. One additional point for the anticipating also earning Site Development-Protect and Restore Habitat Cooling Tower credit will be earned for testing water and maximizing the under a LEED v4.1 methodology, which will include a small pollinator number of cycles allowable. garden. Enerev and Atmosphere: The project is planning light colored roofing and also light colored The project is evaluating HVAC systems and other opportunities for pedestrian hardscaping. Combined with shading associated driveways energy efficiencies in the project. The early phase energy models is with significant new trees, it is anticipated that the project will earn both showing an energy savings of approximately 17%, the project is currently Site Plan Review Statement ALEXAN DRIA. PAGE 1 118 holding 8 points in "Yes" for Optimize Energy Performance. The team Materials and Resources: is still evaluating a series of Energy Conservation measures (see energy One of the most significant changes in LEED v4 is in the Materials and model) which will increase the energy performance of the building, and Resources section. The focus has changed from materials themselves these points are being held as "More Likely" and "Less Likely." PV systems to material transparency. Manufacturers are quickly adapting to this elsewhere on campus could support the achievement of all points in change, with more of the information required to earn these credits the Optimize Energy Performance Credit and also allow three points to becoming available as more EPDs, HPDs, and CSRs are developed. The be earned in the Renewable Energy Production Credit depending upon project will target a minimum of 20 EPDs and 20 HPDs in addition to the structure of the system's purchase and allocation (or purchase) of sourcing materials with sustainability attributes (i.e. recycled content, FSC Renewable Energy Credits to offset renewable production allocated to the wood, rapidly renewable material, C2C certification). This will allow the building. project to earn one point in each of the following Building Discloser and Optimization credits: Environmental Product Declarations, Sourcing of Building commissioning helps ensure that the building meets set Raw Materials, and Material Ingredients. performance goals. LEED v4 offers credits for both building system and envelope commissioning, and enhanced and monitoring-based A whole building life cycle assessment provides the team an commissioning are planned for the project. Envelope commissioning is understanding of the environmental impact of the project construction. also being planned. This study will be conducted and will earn the project three points for the Life-Cycle Impact Reduction credit. In addition, the project will target The project will install meters for future tenant spaces so that tenants will Construction Waste Recycling with 75% diversion, including three waste be capable of independently metering energy consumption (electricity, streams, to earn two points in this credit. chilled water, etc.) for all systems dedicated to their space. This will earn one point in the Advanced Energy Metering credit. Indoor Environmental Qualitv: The Enhanced IAQ Strategies credit will be targeted with a focus on Alexandra Real Estate offsets its energy use with Green Power purchases, filtration, walk off mats, exhausting chemical storage rooms. This will earn and therefore the project is anticipating two points in the Green Power the project one point, and a second is being held as "Maybe" and will and Carbon Offsets credit for purchasing RECs and carbon offsets for continue to be evaluated. In addition, the Construction IAQ Management 100% of the energy use for 5 years. Plan credit will be targeted, and the specifications will require the construction team to develop and implement a plan. It is assumed that environmentally friendly refrigerants will be used, so credits for both fundamental and enhanced refrigerant management are Care in material selection is critical for optimizing credits in this category. anticipated. The Demand Control can be challenging for Core and Shell Unlike LEED 2009, v4.0 & v4.1 looks at emissions of materials, beyond projects, as it requires significant load shedding; however, under LEED VOCs. LEED v4.1 provides opportunities for teams to earn more credits v4.1 there may be an option for compliance, so one point is still being than were available in LEED v4.0, and this path will be pursued. The held as "Maybe." project will target paints and coatings, composite wood, flooring, ceilings, Site Plan Review Statement Arsenal on the Charles I April 8, 2021 PAGE 1 119 and insulation for these credits, and anticipates earning all three points in 8. Screening: the Low-Emitting Materials credit. The floorplate of the project and large expanse of windows makes the Rooftop equipment and enclosed penthouse will be shielded from view Daylight credits unlikely due to glare concerns, and therefore they are by a perforated metal architectural screen wall with a color and finish that not being targeted. The Views Credit may be achievable is appropriate is complementary to the building facade. Ground mounted-equipment sample tenant fit plans are established and this credit is being held as will be screened through a combination of landscape elements (trees and "Maybe." shrubs) and fixed screen walls or fences. Innovation: As with most lab buildings, Building 2 requires a robust loading and The project anticipates earning all credits in the Innovation and Design receiving area to accommodate equipment and material for the lab Category. These credits will be selected to help the project tell the story tenants. For Building 2, the loading dock is located to the east of the that the client is most excited about. Although these credits have yet to building and will be accessed by vehicles from a driveway connecting to be selected, they may include the following: Kingsbury Avenue. To mitigate the visibility of the loading dock, it has • Walkable Project Site been recessed into the landscape and will be shielded from view by a • Designing for Nature heavily landscaped buffer. • Design for Active Occupants • Green Building Education 9. Safety: • O+M Starter Kit • Integrated Analysis of Building Material The campus is accessible by emergency vehicles from Arsenal Street via • WELL Credits Kingsbury and Talcott Avenues as well as from North Beacon Street via • Fitwel Credits School Street. Fire truck access is around the perimeter of the building • Occupant Survey as indicated in the Fire Truck Maneuvering figure attached. The building has two separate egress stairs. One stair exits directly from the building, Regional Priority: the other exits through the lobby. Both exits lead to an easily identifiable The following credits are regional priorities. Additional points are open space away from the building. available for these credits if they are earned at the listed thresholds: • Rainwater Management (3 points) • Optimize Energy Performance (8 points) • Building Life Cycle Impact Reduction (3 points) • Indoor Water Use Reduction (3 points) • Renewable Energy Production (2 points) • High Priority Sites (2 points) 0 Site Plan Review Statement ALEXAN DR IA. PAGE 1 120 10. Design: The Project will be designed to protect abutting properties from detrimental site characteristics resulting from the proposed use by implementing a stormwater management system which will reduce stormwater runoff and water pollutants. Construction related impacts, such as dust and erosion, will be mitigated through the implementation of a construction period Stormwater Pollution Prevention Plan (SWPPP). Building 2 is located toward the interior of the campus and will have limited visibility from surrounding neighborhoods. Where the building is visible from the campus exterior, mitigation measures will be implemented such as landscape buffers and vegetative screening to shield the building from view. The site lighting system will be designed to avoid visual impacts to the abutters in compliance with the zoning requirements and Dark Sky Initiative. Mechanical systems will be high efficiency designed to operate at 90-95% efficiency and to minimize noise levels. Acoustical engineering services have begun and will be continued throughout the design process. Evaluation of the rooftop and ground noise producing equipment will be conducted. Equipment that exceeds comfortable noise levels for the adjacent residential properties will be properly screened and buffered with acoustical barriers. See Renderings showing the new building in the surrounding context for reference. Site Plan Review Statement Arsenal on the Charles I April 8, 2021 PAGE 1 121 Building Massing & Setbacks 1 REFERENCING SCALE The primary facade of Building 2 lifts at the west end of the building to reveal a large, S� activated lobby. The double-height lobby .-- � Snowrapped in transparent glass references the scale of the adjacent buildings and r w - ------ ,1� ,._ provides visibility from the arrival court to the south lawn. 2 EMPHASIZING CORNERS A vertical communicating stair anchors t 0 the corner of Building 2 facing the arrival court. The verticality of this feature stair is © h emphasized by transparent ground level 71 glazing and a glass roof bulkhead. M _ > 3 MASSING VARIATION r, The expressed stair tower, recessed ground floor facade and lifted facade at the lobby provide articulation to the building's massing and reference its surrounding context. � 4 VERTICAL ELEMENTS :. ;.. Vertical C-Channels at the facade express t the building's structural grid and become %. articulated columns at the base. These vertical elements divide the horizontality of the facade and mitigates the building's linear presence. AODD Design Guidelines Summary ALEXAN DR IA. PAGE 1 122 Building Height 1 RANGE OF HEIGHTS/ The glass-enclosed, communicating stair bulkhead extends above the roofline, providing a visual focal point at the corner r of the building.n . or. TV v 2 REFERENCES TO CONTEXT © The height of Building 2 complies with 0 I ] zoning requirements and is harmonious to the scale of adjacent buildings. The a _ building's lobby and feature stair are oriented toward the arrival court and the 0 transparent lobby provides visibility to the © south lawn. 3 MECHANICAL PENTHOUSE Rooftop mechanical equipment and enclosed penthouse are shielded from public view by a perforated metal screen. The screen color and finish complements < t „�• \ the building facade and designed to be compatible with the aesthetic and material language of the building. 4 GROUND FLOOR OVERHANG The recessed ground floor facade protects pedestrians from the elements, reduces 3 'n solar gain, and delineates the base of the building from the upper stories. AODD Design Guidelines Summary Arsenal on the Charles I April 8, 2021 PAGE1123 Facade Treatment & Materials 1 HIGH QUALITY AND NATURAL MATERIALS The material palate for Building 2 draws 11 inspiration from the Arsenal on the Charles .11 site by integrating industrial materials and elements. The metal facade frame , E wood soffits and masonry base evoke ' an industrial aesthetic that compliments the site's existing architecture. A high-performance curtainwall system maximizes the building's energy performance.All selected materials are 4.., durable, resilient, natural and sustainable. 2 TEXTURE, VARIATION,AND TACTILITY The facade of Building 2 references the scale and articulation of historic industrial buildings. The expressed C-Channel frame organizes the facade into bays and ;.� articulated facade elements give it a sense of depth. 3 TERRACES 41 j A rooftop terrace activates the top of the building and softens the edges with F plantings and greenery. AODD Design Guidelines Summary ALEXAN DR IA. PAGE 1 124 ram' -r• ice- a - .�c„dy. . �� x '{E t J � � "�." a.� �. �' 1Fr'` - - ■ tea- ��� .x'4 Z• � - '•p}'��`+�.�' � 1 -- - Y Building Avenue Arsenal on April • 2021 �..r • � Njl q -.�.:\ '?EY �. :'.- :. � ,.✓ � 2r�A X .� ._ rgvt:y,7� .� 4�. C��� ��B"}l�{c.