5.2 sustainability sustainable design strategy...hr eff = 75% offices and daycare vrf central hrv...

78 ACTON OSTRY ARCHITECTS INC Rezoning Application | Cambie & 49th

sustainability sustainable design strategy 5.2

KaneConsultingispleasedtosubmitthisSustainableDesignStrategyonbehalfoftheProjectTeamandOwnershipforCambie&49th,Vancouver,BC.PathB–LowEmissionsGreenBuildingsTothebestofourknowledge,thedesignassubmittedisontargettomeettherequirementsofthepolicy.Thefollowingdescribesthesustainabledesignelementsandstrategiesincludedintheproject:B.1–LEEDGold:Thissectionisnotapplicabletothisproject.B.2–PerformanceLimits:asummaryofstrategiesandmeasurestoachieveperformancelimits,heatlossandGHGisincludedinthefollowingsection.B.6.2–EmbodiesEmissions:thePreliminaryembodiedemissionscalculations,andadescriptionofspecificmeasuresthatwillbeexploredduringdesigntoreduceembodiedemissionsisincludedinthefollowingsectionB.10–SiteIRMPandGreenInfrastructure:thesiteIRMPanddescriptionisincludedinthefollowingsection.OwnerCommitment:TheOwnerCommitmentisincludedinthefollowingsection.Sincerely,DanielRobertsLEEDAPBD+C,CaGBCFacultyCertifiedPassiveHouseConsultantPartnerKaneConsultingPartnership

SustainableDesignStrategy–RezoningSubmissionProject:Cambie&49th,Vancouver,BC Date:December4,2019

79ACTON OSTRY ARCHITECTS INC Rezoning Application | Cambie & 49th


Project AddressSecondary Address

Project Working TitlePOSSE File Name (City use only)

Gross Floor Area indicated on Arch. Drawings (m²) 15,212 Parkade Area (m²) 6,588

Building Type(s) Modelled Floor Area (m²) Rezoning? TEUI TEDI GHGIResidential, 7+ storeys (Group C except Hotel) 10,939 Yes 120 30 6

Office 3,050 Yes 100 27 3Retail (Group D & E except Office) 1,005 Yes 170 21 3

Total 14,994 TEDI limit for this portion of building 28.8

Building Type Modelled Floor Area (m²) Rezoning?

Enter Other Building Type Baseline Model Performance Energy (kWh) Em. Factor Emissions (kgCO2e) TEUI TEDI GHGITotal Annual Electricity Use 0.011 - Baseline: 0 0 0

Total Annual Natural Gas Use 0.185 - Target: 0 0 0Total Annual District Energy Use 0.070 -

Total - - Total Annual Heat Demand - for TEDI

TEUI TEDI GHGITotal Modelled Floor Area (m²) 14,994 Whole-Building Performance Limits 119.3 28.8 5.2

Modelled Floor Area within 5% of Gross Floor Area? Yes

Energy (kWh) Fuel Type Em. Factor Emissions (kgCO2e) TEUI GHGIInterior Lighting 402,529 Electricity 0.011 4427.819 26.8 0.3

Exterior Lighting 8,760 Electricity 0.011 96.36 0.6 0.0Heating 150,168 Electricity 0.011 1651.848 10.0 0.1Cooling 50,901 Electricity 0.011 559.911 3.4 0.0Pumps 24,178 Electricity 0.011 265.958 1.6 0.0

Fans 290,102 Electricity 0.011 3191.122 19.3 0.2Domestic Hot Water 322,593 Natural Gas 0.185 59679.705 21.5 4.0

Plug Loads 267,396 Electricity 0.011 2941.356 17.8 0.2Heating - Natural Gas 0.185 0 0.0

Enter other end use hereEnter other end use here

Total Annual Electricity Use 1,194,034 0.011 13,134 Total Annual Natural Gas Use 322,593 0.185 59,680

Total Annual District Energy Use - 0.070 - Total 1,516,627 72,814

Total Electricity Generated On-Site (kWh) % of Use 0.0%Total Purchased Renewable Electricity (kWh) % of Use 0.0%

Total Purchased Renewable Natural Gas (kWh) % of Use 0.0%

Adjusted Electricity Emissions Factor (kgCO2e/kWh) 0.011Adjusted Natural Gas Emissions Factor (kgCO2e/kWh) 0.185

Annual Heat Demand of portions with Perf. Limits (kWh) - Total Annual Heat Demand - for TEDI (kWh) 434,015

Total Annual Cooling Demand - for info only (kWh) 281,541 18.8 kWh/m²TEUI TEDI GHGI

Modelled Whole-Building Performance 101.1 28.9 4.9

Heating Degree Days 3111Number of Suite Doors Pressurized 115

Airflow for Pressurization per Door (L/s/door) 3.81Area of Corridors Pressurized (m²) 864.3

Make-Up Air Fuel Type Electricity TEUI TEDI GHGIMake-Up Air Emissions Factor 0.011 Adjustments for Corridor Pressurization 1.3 1.3 0.0

Suite-level Metering for Space Heating No Adjustments for Suite Submetering of Heating 1.5

Adjusted TEDI Performance of Portions with Limits (1.3) Adjusted Whole-Building Performance for Compliance 101.3 27.6 4.8

Zero Emissions Building Plan Energy Checklist

Please complete all fields that apply to the project, using information that represents the current stage of design. For fields that do not apply or for which there is no information yet, please enter "N/A".

Note: select yes if the energy used for heating is metered at the suite level

NoNoNo

LimitsBuilding Information and Performance Limits

Project Information (enter all that apply)6409, 6435, 6459 and 6487 Cambie Street

C49 Cambie and 49th

City-Recognized Low Carbon Energy System?

Corridor Pressurization Adjustment

Modelled Building Performance

For building types with Performance Limits, enter this information in this section

Note: purchaes renewables used to demonstrate compliance must be secured to satisfaction of AHJ

For other building types, create a baseline energy model to establish limits, and enter this information in this section

B.2–PerformanceLimits



Summary of Model Inputs Project: C49 Cambie and 49th Issued: December 2, 2019

Building Description The project consists of a ten storey mixed use building and townhouses. The ground floor and mezzanine mainly contain retail units and some residential suites. The second floor contains daycare and office spaces, while the third floor is solely for office spaces. All remaining floors contain residential suites. There is approximately 118,000 ft2 of residential building floor area, 33,000 ft2 of office and daycare floor area and 11,000 ft2 of retail floor area. The above-grade window-to-wall ratio (WWR) is about 41%.

Space conditioning will be provided by VRF systems throughout the building. All above grade ventilation will be heat recovered by systems with at least 75% effectiveness, including ventilation for corridors. Below grade spaces will be freeze protected with electric resistance heat. Domestic hot water will be provided by condensing natural gas boilers.

Inputs Construction thermal properties are as shown in the table below. The above-grade portions of the buildings will be constructed with steel framed walls.

Construction Clear Field U-Values Area (ft2) U·A (Btu/h F) % total heat loss

Steel-framed Wall 0.056 (R18 continuous insulation) 59,195 3,289 17.3% Roof 0.046 (R22) 22,940 1,052 5.5% L1 Floor 0.056 (R18) 21,360 1,193 6.3% Soffit 0.077 (R13) 1,580 122 0.6% Curtainwall 0.41, SHGC = 0.26 (double glazed) 12,684 5,200 27.4% Window Wall 0.41, SHGC = 0.26 (double glazed) 19,866 8,145 42.9%

Default psi values for thermal bridges have been included at this stage to inform the design team of their potential relative importance.

Modelled Above-Ground Wall Area (m²) 7,345 Vertical facade-to-Floor Area Ratio (VFAR) 0.49 Window-to-Wall Area Ratio (WWR) 41% Window-to-Floor Area Ratio 0.20

Infiltration Rate (L/s/m²fac) 0.2Wall Effective R-Value - incl. thermal bridging (m²K/W) 2.1 11.93 (ft²hr°F/Btu) Average Floor Edge Psi-Value (W/m°K) 0Roof Effective R-Value - incl. thermal bridging (m²K/W) 2.8 16.13 (ft²hr°F/Btu) Avg. Window Transition Psi-Value (W/m°K) 0.48

Average Window Effective U-Value (W/m²°K) 2.74 0.48 (Btu/ft²hr°F) Window Solar Heat Gain Coefficient 0.26 Average Suite Occupant Density (m²/pers) 27.3 Average Lighting W/m² 6.81

Average Suite Ventilation Rate (L/s/m²) 0.24 DHW Low-Flow Savings (%) 0Average HRV Effectiveness 75% DHW Drain Heat Recovery Effectiveness n/a

Heating System Type (fuel, plant, distribution, etc.)Cooling System Type (fuel, plant, distribution, etc.)

DHW System Type (fuel, plant, distribution, etc.)

Modeller Name2

CompanyPhone Number

EmailZEBP Energy Checklist v1.5 - 2018-07-27

Ty Bob Consulting Ltd604-390-0035

These results have been created using the COV Energy Modelling Guidelines version:

Modeller Information

Derek Whitehead

VRF

Modelled Inputs

[email protected]

VRF

Natural gas condensing boilers


sustainability sustainable design strategy 5.2Summary of Model Inputs – C49 Cambie and 49th

Page 3 of 3

System assumptions are shown in the table below.

System Fan Power Ventilation Rate Heating Setpt (°F)

Cooling Setpt (°F)

Other

Suites VRF Central HRV (distributed HRVs for townhouses)

0.25 W/cfm

0.40 W/cfm supply and exhaust

Studio, 1 bdrm: 30 cfm 2 bdrm: 45 cfm 3 bdrm: 60 cfm Corridor: 0.1 cfm/ft2

72 (Sch G)

75 (Sch G)

HR Eff = 75%

Offices and Daycare VRF Central HRV

0.3 W/cfm 0.40 W/cfm supply

and exhaust

20 cfm/occ

Corridor: 0.1 cfm/ft2

72 (Sch A)

75 (Sch A)

HR Eff = 75%

Lobbies and Amenities VRF HRV

0.25 W/cfm 0.40 W/cfm supply

and exhaust

20 cfm/occ

72 (Sch C)

75 (Sch C)

HR Eff = 75%

Retail VRF Central HRV

0.3 W/cfm

0.40 W/cfm supply and exhaust

0.30 cfm/ft2

Corridor: 0.1 cfm/ft2

Vestibule Pressurization

0.3 W/cfm 50-100 cfm per space

50 n/a Elec res heat

Parkade 0.16 W/cfm 0.75 cfm/ft2 n/a n/a 4 hr/d Storage Exhaust 0.43 W/cfm 0.15 cfm/ft2 n/a n/a 24 hr/d Heating Only n/a n/a 50 n/a Elec res heat

Derek Whitehead, Director Ty Bob Consulting Ltd.

Summary of Model Inputs – C49 Cambie and 49th

Page 2 of 3

Thermal Bridge Psi Value (Btu/h ft F) Applied to Addn’l heat loss (Btu/h F)

Revised U-Values

Wall/Parkade roof 0.461 L1 floor 541 0.081 Parapet 0.216 Roof 378 0.062 Wall/Window 0.278 Window Wall 2,371 0.529 Balconies Wall Corners

0.465 0.020

Walls 1,677 32

0.084

The model was developed using the City of Vancouver Energy Modelling Guidelines. Gains and schedules are as shown in the table below. Lighting power density is assumed to be 80% of 90.1-2010 prescriptive requirements; storage and service rooms are assumed to be 70% of 90.1-2010 prescriptive requirements; suites lighting power density is taken from City of Vancouver Modelling Guidelines. Elevator energy use and domestic hot water use are also taken from City of Vancouver Modelling Guidelines. No reduction in DHW is currently assumed for the use of low flow fixtures. Energy for kitchen range hoods and suite bathroom exhaust has been assigned to the electrical meter, and equates to 2 hr/day operation with a power draw of 146 W for each suite.

Space type/Use Occupancy ft2/occ (Sch)

Lighting W/ft2 (Sch)

Equipment W/ft2 (Sch)

stair 2,152 (C) 0.55 (Hydro) n/a corridor 1,076 (C) 0.53 (24/7) n/a storage 1,076 (E) 0.44 (Hydro) 0.093 (E) service rooms 2,152 (E) 0.67 (Hydro) 0.093 (E) parkade n/a 0.13 (24/7) n/a elevator lobby 108 (C) 0.51 (24/7) 0.093 (C) retail 323 (C) 1.68 (C) 0.232 (C) lobby 108 (C) 0.72 (24/7) 0.093 (C) amenity 54 (C) 0.58 (C) 0.093 (C) office 215 (A) 0.78 (A) 0.697 (A) parents rm/staff rm 54 (C) 0.98 (C) 0.093 (C) quiet rm/nap rm 108 (B) 0.58 (B) 0.093 (B) WC 323 (C) 0.78 (C) 0.093 (C) kitchen 215 (B) 0.79 (B) 0.929 (B) daycare 81 (D) 0.99 (D) 0.465 (D) suite Occs = Bdrms + 1 (G) 0.465 (G) 0.465 (G) elevator n/a n/a 12 kW (G) domestic hot water n/a n/a 0.025 gpm/occ (G) exterior lighting n/a 2 kW (12 h/d) n/a *Schedules taken from NECB 2011 except for lighting schedules that reference BC Hydro’s New Construction Program’s Energy Modelling Guidelines



49th and Cambie

Rezoning Whole-building Life Cycle Assessment

Prepared by:

Bowick Consulting Ltd. 525 McLeod St.

Ottawa, ON K1R 5P9 613.808.5735

B.6.2–EmbodiedEmissions



2

Cambie and 49th Rezoning WB-LCA

General Assessment Information The purpose of this report is to provide the background information required for submittal of preliminary embodied emission calculations as part of the rezoning application for the proposed project at Cambie & 49th, Vancouver. The results presented were generated using the Athena Impact Estimator for Buildings software. The building complex was modelled using a combination of [1] material quantities imported into the software (estimated by Bowick Consulting) and [2] its “Assembly”1 input dialogs. General information on the assessment

Project Name Cambie & 49th

Assessor Matt Bowick, Principal, Bowick Consulting

Verifier (optional) N/A

Internal External

Date of assessment November 22, 2019

Assessment timing

Schematic Design

Construction

Design Development

Operations & Maintenance

Construction Documents

End of Life

Whole-building LCA Results Life Cycle Assessment Impact Measures Value Unit 2

Global warming potential 5,995,579 kg CO2

275 kg CO2/m2 4.59 kg CO2/m2/yr

Optional metrics Stratospheric ozone depletion 0.0458 kg CFC-11 Acidification of land and water 35,719 kg SO2 Eutrophication 2,374 kg N Tropospheric ozone formation 670,701 kg O3 Depletion of non-renewable energy resources 58,756,401 MJ

1 The “Assembly” dialogs modeling approach is intended for use during early project phases when not all design elements have been formalized. Please note that the building bill of materials calculated for structural elements is based on rules-of-thumb and should be viewed as an estimation. 2 Where relevant, m2 refers to gross floor area (21,770 m2), as calculated per the Canadian Institute of Quantity Surveyors’ (CIQS) Elemental Cost Analysis method and includes parking levels.

3


Assessment Scope

The functional equivalent of the building assessed

Building type Mixed-use (commercial, multi-unit residential), mid-rise

Technical and functional requirements

Technical: Vancouver Building ByLaw (VBBL), Green Building Policy for Rezoning – Process and Requirements. Functional: commercial and childcare space (levels 1-3), plus residential space: 21 studio units, and 36 1-BR, 53 2-BR units, 17 3-BR units. Occupant parking and bicycle storage.

Pattern of use Typical for the functions provided.

Required service life 60 years (assumed, no required service life)

Other information (optional) n/a

Construction elements included in the object of assessment.

A1010 Standard Foundations

B2010 Exterior Walls

C1020 Interior Doors

A1020 Special Foundations B2020 Exterior Windows C2010 Stair Construction

A1030 Slab on Grade

B2030 Exterior Doors

C2020 Stair Finishes

A2020 Basement Walls B3010 Roof Coverings

C3010 Wall Finishes

B1010 Floor Construction B3020 Roof Openings

C3020 Floor Finishes

B1020 Roof C1010 Partitions C3030 Ceiling Finishes

Assessment system boundary

A1 Raw material supply

B2 Maintenance C1 De-construction demolition

A2 Transport

B3 Repair

C2 Transport

A3 Manufacturing

B4 Replacement C3 Waste Processing A4 Transport

B5 Refurbishment C4 Disposal

A5 Construction-installation process

B6 Operational EnergyB6 Operational Energy

B1 Use B7 Operational WaterB7 Operational Water


sustainability 5.2

4


Project Description

Summary description of the assumed proposed building design3

Cambie & 49th is a proposed 10-storey mixed-use building and two-storey townhouse complex with 21,770 m2 total gross floor area. The structure includes two parking levels below grade, a mezzanine within the double-height ground floor space, and several low roof terraces. There are three stair/elevator cores, two of which extend the entire building height. The structure is composed of 275 mm two-way concrete slabs supported by concrete columns (9 m x 7.5 m grid) and concrete basement-level walls. The elevator/stair cores are 350-500 mm thick concrete walls. The slab on grade is 125 mm thick with 50 mm extruded polystyrene insulation and vapour retarder. The foundation structural design has yet to be defined. For the purpose of this assessment, the foundation structure material usage (footings and piers) is based on an estimate from another building of similar size and function, scaled to the total building gross floor area. The building’s wall envelope consists of brick veneer with 100 mm semi-rigid mineral wood insulation and 150 mm light gauge steel stud back-up. The building’s glazing includes aluminum-framed, double-pane window units, and curtain wall at the ground and second floor levels. The roof envelopes are assumed to be 2-ply SBS membrane, with 125 mm extruded polystyrene insulation. Roof areas are covered with ballast, concrete pavers, or an intensive green roof system.

Proposed measures that will be explored during design to reduce embodied emissions.

▪ Selection of lower impact concrete mixes including those that contain supplementary cementitious materials (SCMs) such as fly ash.

▪ Refinement of the concrete structural design, including slab and wall thicknesses, and the foundation design.

▪ Investigations on the use of different envelope products/systems, including cladding, glazing, and insulation alternatives.

Please note: since this assessment is based on a schematic design and material quantification rules-of-thumb, the assessment conducted for building permit may be of higher impact.

3 Please note that the assumed building design is schematic and subject to change

5


LCA Software Summary

General Information

Report template generated by

Software version 5.4.0101

Date this report was created 22 November 2019

Software Data Sources

Life Cycle Scenarios Scenarios used in this assessment come from databases maintained by the Athena Sustainable Materials Institute.

Life Cycle Inventory (LCI) LCI data used in this assessment is from the Athena LCI database and is compliant with ISO 14040 and ISO 14044.

Life Cycle Impact Assessment (LCIA) method TRACI v2.1

See the software's User Manual and Transparency Document for further information on data sources.

LCA Software Inputs

Project Information Baseline/Proposed Building Project Location Vancouver

Units SI

Building Type Multi Unit Owner Occupied

Building Life Expectancy (i.e. reference study period) 60

Building Height (m) 40.15

Gross floor area (m2) 21,770



6


Life Cycle Building Bill of Materials Unit Baseline 1/2" Regular Gypsum Board m2 3,353 1/2" Glass Mat Gypsum Panel m2 5,737 5/8" Regular Gypsum Board m2 5,737 6 mil Polyethylene m2 3,292 Aluminum Extrusion Tonnes 17.5 Aluminum Window Frame kg 5,726 Ballast (aggregate stone) kg 521,441 Coarse Aggregate Crushed Stone Tonnes 1,177 Cold Rolled Sheet Tonnes 1.33 Concrete Benchmark CAN 25 MPa m3 424 Concrete Benchmark CAN 30 MPa m3 9,564 Concrete Brick m2 1,460 Double Glazed Soft Coated Argon m2 4,256 EPDM membrane (black, 60 mil) m2 437 Expanded Polystyrene m2 (25mm) 256 Extruded Polystyrene m2 (25mm) 22,663 FG Batt R11-15 m2 (25mm) 4,096 Galvanized Sheet Tonnes 5.95 Galvanized Studs Tonnes 29.3 Glazing Panel Tonnes 60.7 Joint Compound Tonnes 5.73 Metric Modular (Modular) Brick m2 5,476 Modified Bitumen membrane m2 18,537 Mortar m3 144 MW Batt R11-15 m2 (25mm) 28,194 Nails Tonnes 0.54 Paper Tape Tonnes 0.0657 Polyethylene Filter Fabric m2 7,022 Rebar, Rod, Light Sections Tonnes 1,293 Screws Nuts & Bolts Tonnes 1.69 Solvent Based Alkyd Paint L 23.2 Spandrel Panel Tonnes 4.61 VR 1/2" Drainage Mat m2 5,693 VR 20 mil Root Barrier m2 2,166 VR Intensive Growing Medium m2 (25mm) 9,623

B.10–SiteIRMPandGreenInfrastructure



RAINWATER MANAGEMENT REPORT – DEVELOPMENT PERMIT SUBMISSION CAMBIE STREET & WEST 49TH AVENUE, VANCOUVER, BC

APLIN & MARTIN CONSULTANTS LTD. PROJECT NO. 19-5155 DECEMBER 02, 2019

TABLE OF CONTENTS 11..00 BBAACCKKGGRROOUUNNDD//DDEESSIIGGNN OOBBJJEECCTTIIVVEESS ............................................................................................................................................ 11 22..00 SSIITTEE CCHHAARRAACCTTEERRIISSTTIICCSS.................................................................................................................................................................................................. 22

2.1 SITE LAYOUT ........................................................................................................................ 2 2.2 UNDERGROUND PARKING ............................................................................................ 2 2.3 GROUNDWATER INFLOW ............................................................................................. 2

33..00 RRAAIINNWWAATTEERR MMAANNAAGGEEMMEENNTT SSTTRRAATTEEGGYY .............................................................................................................................. 22 3.1 RAINWATER FLOW ROUTING .................................................................................... 2 3.2 FLOW CONTROL ................................................................................................................ 3 3.3 DETENTION STORAGE .................................................................................................... 3 3.4 TSS REMOVALS ................................................................................................................... 3

44..00 DDEESSIIGGNN PPAARRAAMMEETTEERRSS ........................................................................................................................................................................................................ 44 4.1 DESIGN RAINFALL EVENTS ......................................................................................... 4 4.2 RUNOFF COEFFECIENTS ............................................................................................... 4 4.3 DESIGN RELEASE RATE ................................................................................................. 4

55..00 SSUUMMMMAARRYY ............................................................................................................................................................................................................................................................ 55 AAPPPPEENNDDIICCEESS APPENDIX A CAMBIE ST. & W 49TH AVE. RAINWATER MANAGEMENT PLAN

RRAAIINNWWAATTEERR MMAANNAAGGEEMMEENNTT SSTTRRAATTEEGGYY RREEPPOORRTT For the proposed Development: Cambie Street and West 49th Avenue, Vancouver, BC RRee--IIssssuueedd ffoorr RReezzoonniinngg SSuubbmmiissssiioonn Project No: 19-5155 December 02, 2019 Aplin & Martin Consultants Ltd.




APLIN & MARTIN CONSULTANTS LTD. PAGE 2 PROJECT NO. 19-5155 DECEMBER 02, 2019

2.0 SITE CHARACTERISTICS

2.1 SITE LAYOUT The Cambie Street & West 49th Avenue development site has a total area of 3411 m2

including a road dedication of 1.0m (3 ft. 3 in.) north of the existing south property line. The site is proposed to have a mixed-use commercial/residential building and a residential townhouse building on the northwest of the property, along with pedestrian walkways, planted areas, patios, and underground parking access. The site generally slopes from the northwest corner to the southeast corner. The site features a 3.3m (10 ft. 8 in.) wide City dedication along the east edge of the property, as well as a 3.6m (11 ft. 10 in.) wide City dedication along the new south edge of the property. The proposed site layout is shown on the rainwater management drawings in Appendix A.

2.2 UNDERGROUND PARKING To accommodate the full parking requirements for the development, underground parking will extend up to the north, east edges of the property line. There is a parkade setback of 1.25m (4 ft. 1 in.) from the new property line at the southeast corner which gradually meets the new property line at the southwest corner, as well as a parkade setback of 0.6m (2 ft.) along the west edge of the property line. Due to the location of the underground building, an infiltration system can not be used on site. The underground building footprint outline is shown on the rainwater management drawings in Appendix A.

2.3 GROUNDWATER INFLOW For the purposes of the rainwater management plan design, it is assumed that measures will be implemented to prevent groundwater flows from entering the site storm system. Therefore, groundwater inflows have not been considered in the rainwater management analysis. A geotechnical report will be required to confirm if any special considerations need to be made to accommodate groundwater flows into the parkade perimeter drainage system.

3.0 RAINWATER MANAGEMENT STRATEGY

3.1 RAINWATER FLOW ROUTING The proposed site slopes from northwest to southeast. Therefore, the proposed site will have all rainwater falling on hardscaped surfaces directed to a detention tank in the southeast corner of the site. As mentioned previously, at this stage of the design, onsite non-infiltrating landscape area that can have water directed to them is limited. Where possible, roof runoff will be directed to onsite planters. These locations will be determined as the site landscape design and mechanical design progresses.



1.0 BACKGROUND/DESIGN OBJECTIVES This report has been prepared by Aplin & Martin Consultants Ltd (Aplin Martin) to outline the proposed Rainwater Management Plan for the proposed development at Cambie Street & West 49th Avenue (the site) which is being developed by Gryphon Development (Gryphon). This report is based on the rainwater management requirements provided in the City of Vancouver’s (the City’s) “Rainwater Management Bulletin” (July 11, 2018), and the guidelines in the City’s Engineering Design Manual (2018). The Cambie Street & West 49th Avenue development site is located on the west side of Cambie Street and on the north side of West 49th Avenue and is a consolidation of four existing parcels (6409, 6435, 6459, and 6487). The 0.34-hectare site is bounded by Cambie Street to the east, a lane to the west, West 49th Avenue to the south, and an existing mixed-use building to the north. The rainwater management system is designed based on the City’s Rainwater Management Bulletin. The specific targets are as follows: • VVoolluummee RReedduuccttiioonn TTaarrggeett:: Capture 24 mm of rainfall in 24-hours (equivalent to 70%

of the average annual rainfall volume) from all surfaces on site, prioritizing Tier 1 (infiltration into in-situ soils, rainwater harvesting & re-use, and green roofs) where possible.

• RReelleeaassee RRaattee TTaarrggeett:: Peak flow runoff rate discharging to the City storm system from the site shall be limited to the pre-development peak flow rate. The pre- and post-development runoff rates were calculated using the City’s 2014 and 2100 IDF curves respectively for a 5-year storm event and a time of concentration of 10 minutes for all calculations.

• WWaatteerr QQuuaalliittyy TTaarrggeett:: The first 24 mm of rainfall for all the hard surfaces (for impervious surfaces with high pollutant loads, e.g. a driveway, it will be the first 48mm) shall be treated to remove 80% of Total Suspended Solids (TSS).

For the site, a Tier 3 strategy will be employed to meet the volume retention target. The Tier 1 stormwater volume retention objectives cannot be met due to the proposed underground building footprint; the available space for an engineered infiltration system that will not drain back into the building perimeter drain is limited. The area available for Tier 2 non-infiltrating landscape measures that can have runoff water directed to them is limited. Where possible, roof runoff will be directed to onsite planters. These locations will be determined as the site landscape design and mechanical design progresses. At this time, it is assumed Tier 2 facilities cannot fully meet the volume reduction target; therefore, a Tier 3 facility will be provided. The release rate target is met given that the Tier 3 rainwater management facility will have sufficient storage volume to meet the detention volume required to attenuate peak flow rate.





The approximate flow direction of the rainwater is shown on the rainwater management drawings in Appendix A.

3.2 FLOW CONTROL A flow control orifice of 110mm diameter will be provided downstream of the detention system to limit the post-development peak flow rate entering the City drainage system to the pre-development flow rate (based on the CoV 2014 IDF curve). An assumed height of 1.0m was used for the detention storage system and is subject to change as the architectural design and mechanical design progresses. The approximate location of the flow control device and the flow control orifice size calculation is shown on the rainwater management drawings in Appendix A.

3.3 DETENTION STORAGE A detention system with a minimum capacity of 13.30m3 will be placed in the southeast corner of the site to capture the required onsite rainwater from the hardscape surfaces. The required detention was determined using 5-year storm event data with a 10-minute time of concentration, the CoV 2014 IDF curve for the pre-development peak flow rates, and the CoV 2100 IDF curve for post-development peak flow rates, then applying the rational method. The capacity of the storage tank is based on the release flow rate achieved with the 110mm diameter flow control orifice. The detention storage volume calculations are shown on the rainwater management drawings in Appendix A.

3.4 TSS REMOVALS Water quality TSS removals will be achieved using a CDS Unit mechanical oil/grit separator, designed to meet the 80% TSS removal outlined in the City’s Rainwater Management Bulletin. The CDS unit will be placed upstream of the detention storage system to minimize maintenance requirements for the detention system. The approximate location of the CDS Unit is shown on the rainwater management device drawings in Appendix A.



4.0 DESIGN PARAMETERS 4.1 DESIGN RAINFALL EVENTS Pre-development peak flow rates are based on the City of Vancouver’s 2014 IDF curve. Post-development peak flow rates are based on the City of Vancouver’s 2100 IDF curve. Detention storage is based on the 5-year rainfall event using a 10-minute time of concentration for all calculations as per the City’s Rainwater Management Bulletin and the City’ Engineering Design Manual. A post-development peak release flow rate below the pre-development peak flow rate is achieved using a flow control device.

4.2 RUNOFF COEFFECIENTS Runoff coefficients were calculated on a sitewide basis using runoff coefficients primarily based on Table 5-2 found in section 5.2.2.1 of the City of Vancouver Engineering Design Manual, with specific notes as follows:

• Runoff coefficients for building roofs are taken directly from the City’s Engineering Design Manual.

• Runoff characteristics for the existing asphalt pavement surfaces within the site are assumed to be similar to “Asphalt Streets” in the City’s Engineering Design Manual.

• Runoff characteristics for the proposed hardscape surfaces within the site are assumed to be similar to “Concrete Streets” in the City’s Engineering Design Manual, as a worst-case scenario.

• Runoff characteristics of the proposed landscape areas are assumed to be similar to “Average (2-7%) Lawns, Heavy Soil” in the City’s Engineering Design Manual.

Table 1 below summarizes the runoff coefficients for the various surface types used in the analysis.

TTaabbllee 11:: SSuurrffaaccee TTyyppee//DDeevveellooppmmeenntt RRuunnooffff CCooeeffffiicciieenntt

BBuuiillddiinngg

RRooooff LLaannddssccaappeedd

AArreeaass AAsspphhaalltt

PPaavveemmeenntt PPrrooppoosseedd

hhaarrddssccaappeess

RRuunnooffff CCooeeffffiicciieenntt

0.85 0.23 0.83 0.88

The various surface treatments are shown on the rainwater management drawings in Appendix A.

4.3 DESIGN RELEASE RATE Per the City’s Rainwater Management Bulletin and the City’s Engineering Design Manual, the post-development peak flow rate target for the site shall be limited to the pre-development peak flow rate for the 5-year return period rainfall event with a 10-minute time of concentration, utilizing the City’s 2014 IDF curve.





Table 2 below shows the calculation of the sitewide release rate using the rational method. The resultant pre-development peak flow target for the site is 0.027 m3/s.

TTaabbllee 22:: PPrree--DDeevveellooppmmeenntt PPeeaakk FFllooww RRaattee CCaallccuullaattiioonn

TTiimmee ooff

CCoonncceennttrraattiioonn ((mmiinn))

RRuunnooffff CCooeeffffiicciieenntt

AArreeaa ((HHaa))

IInntteennssiittyy 55--yyeeaarr ssttoorrmm

((mmmm//hhrr)) nn

QQ ((mm33//ss))

Qpre (2014 IDF)

10 0.54 0.3411 52.99 0.00278 0.027

Understanding that a maximum peak release rate of 0.027 m3/s needs to be met, a 111.88mm diameter orifice is required. Using a standard sized orifice of 110mm diameter, a peak release rate of 0.026 m3/s is achieved. Peak flow calculations and orifice sizing calculations are also shown on the rainwater management drawings in Appendix A.

5.0 SUMMARY In summary, the rainwater management system is designed based on the City’s “Rainwater Management Bulletin” (July 11, 2018), and the guidelines in the City’s Engineering Design Manual (2018). The analysis results can be summarized as follows:

• Tier 3 rainwater management facility will be used on site.

• The available space for an engineered infiltration system that will not drain back into the building perimeter drain is limited due to the proposed underground building footprint. Therefore, a Tier 1 rainwater management facility will not be used.

• Non-infiltrating landscape measures that can have runoff water directed to them is limited. Where possible, roof runoff will be directed to onsite planters. These locations will be determined as the site landscape design and mechanical design progresses. At this time, it is assumed that Tier 2 management facilities cannot fully meet the volume reduction target.

• The post-development peak flow rate discharged from the site shall be limited to the pre-development peak flow rate for the 5-year rainfall event, using a 10-minute time of concentration, calculated based on the City’s 2014 IDF curve. Based on these parameters, the post-development peak release flow rate discharged from the site shall be equal to or less than 0.027 m3/s.

• Detention storage of 13.30m3 will be provided on the southeast corner of the site. Using a 110mm flow control device, total post-development peak release flow rate discharged from the site will be designed to be 0.026 m3/s. Therefore, the rainwater management plan meets the peak flow target.

• Water quality targets (80% TSS removal) will be achieved using a CDS unit, which

will be located upstream from the detention system to minimize maintenance requirements and maintain long-term function of the detention system.



We trust that the above information is helpful in outlining the proposed rainwater management strategy and design for the Cambie Street and West 49th Avenue development site. Should you have any question or concern, please do not hesitate to contact the undersigned. AAPPLLIINN && MMAARRTTIINN CCOONNSSUULLTTAANNTTSS LLTTDD.. RReevviieewweedd BByy::

Robert Lew, P.Eng. Project Engineer Enclosure 19-5155rsllt01.docx



RAINWATER CATCHMENT ANALYSISPRE & POST CONDITIONS

0 5 25m1:500

01 OF 0201

CAMBIE STREET & W. 49TH AVENUE, VANCOUVER, BC

GRYPHON DEVELOPMENT

19-5155

19-5155 -

CLIENT:

PROJECT:OCTOBER, 2019

2Aplin & Martin Consultants Ltd.

#1818 – 1177 West Hastings Street Vancouver, B.C. V6E 2K3Tel: (604) 678-9434, Fax: (604) 597-9061, Email: [email protected]

PH. 604-620-82966107 WEST BOULEVARD, VANCOUVER, BC, V6M 3X3

6409, 6435, 6459, 6487 CAMBIE STREET, VANCOUVER, BC, V5Z 3B2

PRE-CONSTRUCTION AREASAND RUNOFF COEFFECIENTS

CA

MB

IE S

TRE

ET

W. 49TH AVENUE

LAN

E

CA

MB

IE S

TRE

ET

W. 49TH AVENUE

LAN

E

LEGEND:

BUILDING ROOF

ASPHALTPAVEMENT

GREENSPACE

PROPOSED PROPERTYLINE

EXISTING PROPERTYLINE

LEGEND:

BUILDING ROOF

PROPOSED HARDSCAPE

LANDSCAPED AREAS(ASSUME MIN. 0.3m DEPTH)

PROPOSED PROPERTY LINE

EXISTING PROPERTY LINE

PROPOSED S.R.W. SETBACK

PRE-CONSTRUCTION STAGECATCHMENT AREAS

POST-CONSTRUCTION STAGECATCHMENT AREAS

POST-CONSTRUCTION AREASAND RUNOFF COEFFECIENTS



RAINWATER MANAGEMENT PLAN

0 5 25m1:500

02 OF 0202

CAMBIE STREET & W. 49TH AVENUE, VANCOUVER, BC

GRYPHON DEVELOPMENT

19-5155

19-5155 -

CLIENT:

PROJECT:OCTOBER, 2019

2Aplin & Martin Consultants Ltd.

#1818 – 1177 West Hastings Street Vancouver, B.C. V6E 2K3Tel: (604) 678-9434, Fax: (604) 597-9061, Email: [email protected]

PH. 604-620-82966107 WEST BOULEVARD, VANCOUVER, BC, V6M 3X3

6409, 6435, 6459, 6487 CAMBIE STREET, VANCOUVER, BC, V5Z 3B2

MODIFIED RATIONAL METHOD CALCULATIONSFOR CAMBIE STREET & W. 49TH AVENUE

2. CITY OF VANCOUVER RAINWATER RELEASE RATEREQUIREMENT

³

CA

MB

IE S

TRE

ET

W. 49TH AVENUE

LAN

E

LEGEND:

BUILDING ROOF

PROPOSED HARDSCAPE

PLANTING AREAS(ASSUME MIN. 0.3m DEPTH)

OUTLINE OF UG BLDGFOOTPRINT

PROPOSED PROPERTY LINE

EXISTING PROPERTY LINE

PROPOSED S.R.W. SETBACK

FLOW DIRECTION

3. CITY OF VANCOUVER WATER QUALITYREQUIREMENT

³

³