(IRMP) H S T ST (NORTH TOWER , VANCOUVER BC

150-6450 Roberts Street, Burnaby, BC V5G 4E1 604-298-2333

PRELIMINARY INTEGRATED RAINWATER MANAGEMENT PLAN (IRMP)

1065 HARWOOD ST & 1332 THURLOW ST (NORTH TOWER), VANCOUVER BC

BOSA BLUESKY PROPERTIES C/O HENRIQUEZ PARTNERS ARCHITECTS

VECTOR PROJECT NO.: 2513 REV. 0, MARCH 11, 2021

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Page 1 of 10

Preliminary Integrated Rainwater Management Report 1065 Harwood & 1332 Thurlow (North Tower), Vancouver BC

Rev. 0, March 11, 2021

CONTENTS PAGE NO.

1.0 INTRODUCTION ................................................................................... 2 2.0 EXISTING CONDITIONS .......................................................................... 2 3.0 PROPOSED DEVELOPMENT ..................................................................... 2 4.0 STORMWATER MANAGEMENT OBJECTIVES & BEST MANAGEMENT PRACTICES (BMPS) ................................................. 3 5.0 HYDROLOGIC MODEL AND ANALYSIS ........................................................ 7 6.0 MAINTENANCE GUIDELINES ................................................................... 8 7.0 CONCLUSION .................................................................................... 10 Appendix 1 – Preliminary IRMP Pre-Development Plan

Appendix 2 – Preliminary IRMP Post-Development Plan

Appendix 3 – Hydrographs Pre & Post Development Appendix 4 – Landscaping Design and Soil Loading Diagram

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Rev. 0, March 11, 2021

1.0 INTRODUCTION Vector Engineering Services Ltd has been retained to provide civil engineering design and Preliminary Integrated Rainwater Management Plan design on behalf of Bosa BlueSky Properties, located at 1065 Harwood & 1332 Thurlow St (North Tower), in Vancouver, BC. The subject site is located at the North corner of the intersection of Thurlow Street with Harwood Street (see aerial photo in Appendix 1). As a condition of development, the City of Vancouver has requested a Preliminary Integrated Rainwater Management Plan for the site. In response to this requirement, Vector Engineering Services Ltd. was retained to provide analysis of the site drainage and establish a Preliminary Integrated Rainwater management strategy for the proposed new development. The hydrologic calculations and storm modeling of the site are summarized in this report and are hereby submitted to the City for review. 2.0 EXISTING CONDITIONS The subject site is approximately 0.1608 hectares in area, consisting of two 2-storey residential buildings. The current ground cover condition at the site is 88% impervious. The site currently slopes toward the south, south-west direction (see Appendix 1 for the preliminary IRMP pre-development plan). 3.0 PROPOSED DEVELOPMENT

The development plan calls for construction of a 34-storey high-rise residential building with 7 levels of underground parkade and storage. With the proposed development of the site, the total overall impervious site coverage will decrease to 72%. The impervious areas will consist of building roofs, pedestrian rest areas, parkade ramp and hard landscaped areas. The remainder of the site will consist of a variety of landscaped areas, above the parkade roof slab. Permanent intensive green areas with significant soil depths ranging from 450 mm to 1,200 mm are located on the building podium. These areas represent 28% of the total site area. Intensive green roofs will also be provided on the upper tower roofs (see Appendix 4 for landscaping plan). The weighted runoff coefficient for the proposed development was obtained using the following assumed coefficients based on CoV Engineering Design Manual (2018):

• Landscaped areas at 0.18

• Roof areas at 0.85

• Walkways and driveways at 0.88

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Rev. 0, March 11, 2021

4.0 STORM WATER MANAGEMENT OBJECTIVES AND BMPS To improve the quality of rainwater runoff and improve health of natural water bodies, the City of Vancouver has adopted a City Wide Integrated Rainwater Management Plan and a Rezoning Policy for Sustainable Large Developments. This plan requires all new developments requiring rezoning to incorporate rainwater management measures to control post development runoff rates and to improve the quality of rainwater runoff using Best Management Practices. The rainwater management system for this site has been designed in accordance with the City Wide Integrated Rainwater Management Plan criteria and the Rezoning Policy for Sustainable Large Developments requirements. As per City of Vancouver Rainwater Management Bulletin dated July 2018, we have considered options to reduce stormwater discharge volume, reduce the flow rate of peak runoff, and treat surface runoff to reduce contaminants. The proposed measures shall meet the following targets:

• Capture the first 24mm of rainfall in 24 hours.

• Provide post-development 10-year storm (2100 IDF) runoff release rate of lower or equal rate to the pre-development peak runoff rate for the 10-year 24-hour duration storm (2014 IDF).

• Remove at least 80% of Total Suspended Solids (TSS) by mass from the first 48mm of rainfall over highly polluted areas including driveways and parking, and the first 24mm of all other areas including all walkways, landscaped and roof areas from all levels, before releasing the runoff to the municipal drainage system.

Additional references include the Metro Vancouver Stormwater Source Control Design Guidelines and the Land Development Guidelines for the Protection of Aquatic Habitat which was developed jointly by the Department of Fisheries and Oceans Canada and the British Columbia Ministry of Environment, Lands and Parks (M.O.E.). The source controls adopted for this development consist of several measures to be implemented onsite. The source controls are shown on the attached drawing, Preliminary Integrated Rainwater Management Plan and are summarized below.

4.1 Capture 24mm in 24 hours

To reduce the runoff generated from the site, the stormwater system will capture the first 24mm of rainfall from all areas on the site and retain it as much as possible, given site constraints.

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Rev. 0, March 11, 2021

Remaining volume not retained will be detained, treated for quality and released to the city drainage system. The target for the proposed site is to capture and infiltrate, retain, or treat and detain the first 24mm of rainfall in 24 hours: (24mm x 1608m2) = 38.59m3 of runoff.

4.1.1 Tier 1 Priority Green Infrastructure Practices – Rainwater Harvesting for

Reuse

The primary purpose of rainwater harvesting is to reduce domestic water demand and runoff from impermeable surfaces. Rainwater harvesting involves collecting rainwater and storing it for non-potable uses. The City criteria for using rainwater harvesting is to use the harvested rainwater within a 96-hour period all year round. The use of harvested rainwater for irrigation, non-potable water use, cannot meet this criterion or is very costly at this design stage and therefore the rainwater harvesting source control option has been disregarded.

4.1.2 Tier 2 Priority Green Infrastructure Practices – Retention within Non-

Infiltrating Landscape

Proposed vegetated landscaped areas on all levels will be utilized to retain the required volume of rainfall. Redirection of rainwater surface run-off into the absorbent soil layers will increase the time of concentration and decrease peak storm runoff through evapotranspiration, storage within the soil voids and the holding capacity of the soil particle surface pores. For the purpose of this study, it is assumed that the growing medium has an absorption capacity equal to 20% of the total volume of the soil. The landscaping plan calls for absorbent landscaping areas with soil thickness varying from 450mm in shrub landscaped areas to 1,200mm in treed areas. Finally, any excess moisture in the soil will be collected with a perforated pipe and drained into the mechanical drainage system or overflowed into a drainage facility. Details will be provided at detail design stage.

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Rev. 0, March 11, 2021

Soil retention capacities on each level are presented in the following table:

Level Soil

Depth Landscaped

Area (m2) Volume

(m3)

Soil Retention Capacity

Retention Capacity

(m3) Level 1 900 136.46 122.81 20% 24.56

Level 1 1,200 21.36 25.63 20% 5.13

Level 2 600 28.89 17.33 20% 3.47

Level 2 900 53.61 48.25 20% 9.65

Level 3 450 20.73 9.33 20% 1.87

Level 3 900 133.67 120.30 20% 24.06

Level 34 900 3.72 3.35 20% 0.67

Roof Level 450 10.43 4.69 20% 0.94

Roof Level 900 43.41 39.07 20% 7.81

Total 452.28 390.77 78.15

The total soil volume provided is 390.77 m3 which will have a rainfall volume retaining capacity of 78.15 m3. The hard landscaping such as walkways, pedestrian rest areas and other hard landscaping will be graded to drain towards the adjacent soft landscaped areas, which will be provided with an overflow catch basin tied into the site drainage system inside the underground parkade structure.

Rain Gardens & Infiltration Bulges

The primary purpose of the rain garden and infiltration bulges is to capture and filter runoff from adjacent impermeable surfaces. We propose that the existing bulge on Thurlow Street remain.

Green Roof

The proposed tower will have intensive green roof on the upper roof as detailed on the landscaping plan. The overhang and ground plan surfaces will incorporate significant areas of intensive green roofs. The significant volumes of absorbent soil will be placed on the intensive green roof areas which will provide the benefits outlined in section 4.1.2 above.

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Rev. 0, March 11, 2021

4.1.3 Tier 3 Priority Green Infrastructure Practices – Mechanical Detention and treatment

Detention tanks collect and store stormwater runoff during a storm event, then release it at controlled rates to the downstream drainage system, thereby attenuating peak discharge rates from the site. The detention tank shall capture the amount of 24mm of rainfall in 24 hours falling over areas that are not graded to drain towards the adjacent soft landscaped areas.

Estimated area = 636.44 m2 Detention volume required = 15.3 m3 Required flow rate = 3.61 L/sec = 0.00361m3/sec

See Min. Detention Hydrograph and Storage Volume diagrams in Appendix 3. Details of the detention and treatment system will be provided at detailed design stage.

4.2 Stormwater Flowrate Reduction to Predevelopment Levels:

Detention volume required to meet the City of Vancouver peak runoff reduction to the ten-year 24-hour (2014 IDF Curve) pre-development level of 0.0289m3/sec is equal to 0.327 m3. However, since a slower flowrate of 0.00361m3/sec is needed to meet the detention requirement, this objective is met with the lower flowrate. The detention facility will be located at the north-east corner of lot, underneath the bike share area (location subject to change). The volume the tank must accommodate will be 15.3m3. The release rate will be controlled by a flow control system situated inside the tank outlet with an appropriately sized orifice. See post-development IRMP drawing in Appendix 2. The details of the detention tank and flow control system will be provided at detailed design stage. See Min. Detention Hydrograph and Storage Volume diagrams in Appendix 3. Details of the detention and treatment system will be provided at detailed design stage.

4.3 Water Quality

According to the City of Vancouver Rainwater Management Bulletin dated July 2018, landscaped planted areas with a minimum soil depth of 450mm are assumed to sufficiently treat runoff resulting from the first 48mm of rainfall over highly contaminated surfaces including driveways, parking and loading areas and the first 24mm of all other areas including walkways and roof. In addition, this plan includes the installation of a treatment system to remove at least 80% of total suspended solids (TSS) by mass from the runoff before releasing the flow into the municipal drainage system (CoV Rainwater Management Bulletin, 2018). The details of the treatment system will be provided at detailed design stage. See Post Development IRMP drawing for a general layout of the system.

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Rev. 0, March 11, 2021

5.0 HYDROLOGIC MODEL AND ANALYSIS

The following drainage modeling and analysis was used for design of the Stormwater Management System for this project.

5.1 Rainfall Data

The rainfall data used in the hydrologic analysis was based on the ten-year return period rainfall, as per the City’s Stormwater Management Design Criteria and City of Vancouver Rainwater Management Bulletin dated July 2018. The City of Vancouver IDF curve (2014) rainfall data for pre-development conditions, and IDF curve (2100) rainfall data for post-development conditions were used for the analysis (Appendix 3).

5.2 Existing Runoff

To simulate the ten-year stormwater runoff for the existing condition, the Rational Method was used. An overall runoff coefficient of 0.70 was compiled based on assumed coefficients for various ground covers as provided by CoV Design Guidelines. The time of concentration was assumed to be 5 minutes as indicated in the CoV 2014 IDF. Finally, a 10-year storm was used for the analysis as required by CoV Rainwater Management Bulletin for systems in the downtown core (west of Main Street includes all of the West End peninsula).

Based on the described parameters above, the peak runoff value and volume for the ten-year storm event was calculated to be as follows: Five-year existing peak flow and total rain volume Existing Site Q10yr = 0.0289 m3/sec Total rain volume V10yr = 8.679m3 Allowable Release Rate In accordance with the City Vancouver Integrated Rainwater Management Design Criteria, allowable release rate = Existing Q10yr

Max. Q10yr, prop = 0.0289 m3/sec

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Rev. 0, March 11, 2021

A copy of the modeling results for existing pre-development conditions has been attached in Appendix 3. 5.3 Post Development Runoff

The post development stormwater runoff was also analyzed and hydrologic models were computed using the Modified Rational Method. The following parameters were assumed for the analysis, based on the CoV Rainwater Management Bulletin and the CoV Engineering Design Manual:

• Overall Runoff coefficient = 0.66 (weighted average of all types of ground covers)

• The analysis was conducted using a 10-year 2100 IDF curve data

• A Time of Concentration of 5 minutes was assumed, as per the Rainwater Management Bulletin.

Based on the described parameters above, the peak runoff flowrate and volume for the ten-year rainfall event for the City of Vancouver IDF curve (2100) was calculated as follows: Ten-year 24-hour post development peak flow and volume Proposed Site Q10yr = 0.0300 m3/s Total rain volume V10yr = 9.006 m3 A copy of the post-development conditions results has been attached in Appendix 3.

6.0 MAINTENANCE GUIDELINES The absorbent landscaping is a key component of the proposed Stormwater Management Plan for this development. It has been designed as a permanent low-maintenance system requiring regular monitoring and periodic maintenance. Monitoring and maintenance of individual components of the system will consist of the following measures described below: Catchbasins and Oil-Water Separators

• Inspect oil-water separator and all catch basins for debris and sediment accumulation.

• Remove grate/lid.

• Remove debris as found.

• Remove accumulated sediment and oil using truck mounted suction pump equipment with storage tank when sediment reaches ½ of the sump depth.

• Sediment shall be disposed offsite at an approved landfill.

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Rev. 0, March 11, 2021

• Replace grate/lid.

• All catchbasins to be recharged with clean water after silt/sediment removal. Landscaping

Monitoring (annually by Landscape Architect):

• Inspect plants for die-back, for growth and for general health.

• Observe extent of yearly dieback.

• Forward growing medium sample to laboratory for testing if general plant health in question.

• Inspect plants for signs of pests or diseases.

• Inspect plants for breakage or wind damage.

• Review lawn maintenance operations.

• Observe plant and planter maintenance, weed and debris removal.

• Observe growing medium settlement.

• Review planter edging, flashing, gravel borders.

• Inspect for standing water, saturation or other indications of poor drainage.

• Review irrigation system function and coverage where applicable.

• Prepare annual report.

Maintenance Operations (by maintenance contractor):

• Perform establishment maintenance operations to BCSLA/BCLNA BC Landscape Standard, latest edition for 55 days from Substantial Performance.

• Perform general maintenance operations to BCSLA/BCLNA BC Landscape Standard, latest edition after 55 days from Substantial Performance.

• Replace dead or dying plant materials regularly.

• Fertilize plant materials per plant requirements.

• Respond to laboratory soil test recommendations if indicated.

• Perform pest/disease management as required.

• Prune dead, diseased or broken branches, prune shrubs and trees for form and to optimize flowering yearly.

• Perform standard lawn maintenance operations regularly.

• Stabilize trees or shrubs where indicated.

• Remove weeds, debris and cultivate growing medium regularly.

• Add soil amendment where soil settlement has occurred yearly.

• Maintain and repair edging, flashing, and gravel borders as required.

• Observe, report and perform drainage improvements where indicated.

• Adjust irrigation system regularly for coverage.

• Repair irrigation system leaks immediately.

APPENDIX 1

PRELIMINARY IRMP – PRE-DEVELOPMENT PLAN

UE

PIPE

METAL FENCE

D/W

DO

OR

WA

Y

CO

NC

.

WALKCONC.

WA

LKC

ON

C.

CONCWALK

CONC.WALK

DOORWAY

CONC.WALK

HARWOOD STHARWOOD ST

MAXINE LANE

EOAEOA

EOAC

ON

C. S

/W

CO

NC

. S/W

CONC. D/WCONC. S/W CONC. S/W

CONC. S/WCONC. S/W

CONC. S/W

CO

NC

. S/W

CO

NC

. S/W

CO

NC

. S/W

CONC. S/W

CONC.RET.WALL

CO

NC

. RE

T. W

ALL

CO

NC

. WA

LK

CO

NC

RE

TE

#1100

#1050

#1030

#133

2

#1065

WA

LKC

ON

C.

CO

NC

. S/W

12 13

1110PLAN 92 PLAN 92

20

D

W 25' 8STRATAPLAN VR1437

BRICK

BR

ICK

CONC. RET. WALL

1Rem 8

B L O C K 13

TOP OF SLOPE

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NT

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PLA

NT

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PLA

NT

ER

PLA

NT

ER

CO

NC

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T. W

ALL

#1066

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EB

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6.40323 DEAD GAS

2.70

114

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GA

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114

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GA

S

42m

m G

AS

21m

m G

AS

4.88

300m

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0.91200mm VCP STM

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4.40

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10.0

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CP

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0mm

VC

P S

AN

7.60TELUS

7.60TELUS

1x4"

HY

DR

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UC

T

TH

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LOW

ST

200mm VCP STM

1065 HARWOOD STREET / 1332THURLOW STREET (NORTH TOWER)

VANCOUVER, BC

1:250H (24"X34" PAPER) FEB 2021

AM AM

RU VS

0

DESIGN

IMPORTANT:CONTRACTOR IS RESPONSIBLE TO SCOPE AND EXPOSE EX. UTILITIES/SERVICES, ANDRECORD LOCATION, SIZE & INVERT ELEVATIONS AT PROP. OR POTENTIAL CROSSINGSPRIOR TO CONSTRUCTION. THE AS-BUILT UNDERGROUND INFORMATION SHOWN ONTHIS DRAWING IS DERIVED FROM THIRD PARTY RECORDS AND VECTOR ENGINEERINGIN NO WAY WARRANTS IT'S ACCURACY. REPORT ANY DISCREPANCIES AND/ORCONFLICTS TO CONTRACT ADMINISTRATOR PRIOR TO CONSTRUCTION.

2513 BOSA BLUE SKY PROPERTIES

REV NO REVISIONS DATE DRAWN DESIGN

0 ISSUED FOR REZONING APPLICATION 10 MAR 2021 AM AMvectoreng.ca

604 298-2333

ENGINEERING

PRELIMINARY IRMPPREDEVELOPMENT

THE SEAL ON THIS DRAWING SIGNIFIES CERTIFICATION OF

CIVIL ENGINEERING ASPECTS OF THIS SITE, BUT DOES NOT

SIGNIFY RESPONSIBILITY FOR GEOTECHNICAL OR

ENVIRONMENTAL ENGINEERING DESIGN. IN NO WAY DOES

VECTOR ENGINEERING SERVICES LTD. OR ITS EMPLOYEES

ACCEPT LIABILITY OR WARRANTY THE WORK WITH RESPECT

TO THE EFFECT OF SETTLEMENT ON THE CIVIL WORKS.

PRE-DEVELOPMENT 10 YEAR 24HOUR (2014 IDF) PEAK FLOW = 0.0289m3/secPRE-DEVELOPMENT 10 YEAR 24HOUR (2014 IDF) AVERAGE FLOW = 0.0145m3/secPRE-DEVELOPMENT 10 YEAR 24HOUR (2014 IDF) RAINFALL VOLUME = 8.679m3

SEE ARCHITECTURAL DRAWINGSFOR BUILDING DETAILS

SITE AREA =1608m² = 0.1608 ha.RUNOFF COEFFICIENT = 0.70Tc = 5min

PLOT DATE: March 9, 2021

SCALE START DATE

DRAWN BY DESIGN BY

CHECKED BY APPROVED BY

DWG. NO.

REV.

DESIGN NO.

DESTROY ALL PRINTS BEARING PREVIOUS NO.

VECTOR JOB NO. CLIENT

SWM2OF1

DATUM-GEODETICBENCHMARK: MON. V-3508 ATHARWOOD ST AND BUTE STELEV = 27.850m CVD28GVRD DATUM

SITE

APPENDIX 2

PRELIMINARY IRMP – POST-DEVELOPMENT PLAN

UE

PIPE

METAL FENCE

D/W

DO

OR

WA

Y

CO

NC

.

WALKCONC.

WA

LKC

ON

C.

CONCWALK

CONC.WALK

DOORWAY

CONC.WALK

HARWOOD STHARWOOD ST

MAXINE LANELANE

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EOA

EOA

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. S/W

CO

NC

. S/W

CONC. D/WCONC. S/W CONC. S/W

CONC. S/WCONC. S/WCONC. S/W

CONC. S/W

CO

NC

. S/W

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CO

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. RE

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CO

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2

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C.

12

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A

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W 25' 8STRATAPLAN VR1437

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1Rem 8

PLA

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NT

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114

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21m

m G

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4.88

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5.00

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m V

CP

ST

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8.50

200m

m V

CP

SA

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1x4"

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UC

T

TH

UR

LOW

ST

200mm VCP STM

1:250H (24"X34" PAPER) FEB 2021

AM AM

RU VS

0

DESIGN

IMPORTANT:CONTRACTOR IS RESPONSIBLE TO SCOPE AND EXPOSE EX. UTILITIES/SERVICES, ANDRECORD LOCATION, SIZE & INVERT ELEVATIONS AT PROP. OR POTENTIAL CROSSINGSPRIOR TO CONSTRUCTION. THE AS-BUILT UNDERGROUND INFORMATION SHOWN ONTHIS DRAWING IS DERIVED FROM THIRD PARTY RECORDS AND VECTOR ENGINEERINGIN NO WAY WARRANTS IT'S ACCURACY. REPORT ANY DISCREPANCIES AND/ORCONFLICTS TO CONTRACT ADMINISTRATOR PRIOR TO CONSTRUCTION.

2513 BOSA BLUESKY PROPERTIES

REV NO REVISIONS DATE DRAWN DESIGN

0 ISSUED FOR REZONING APPLICATION 10 MAR 2021 AM AMvectoreng.ca

604 298-2333

ENGINEERING

PRELIMINARY IRMPPOST DEVELOPMENT

THE SEAL ON THIS DRAWING SIGNIFIES CERTIFICATION OF

CIVIL ENGINEERING ASPECTS OF THIS SITE, BUT DOES NOT

SIGNIFY RESPONSIBILITY FOR GEOTECHNICAL OR

ENVIRONMENTAL ENGINEERING DESIGN. IN NO WAY DOES

VECTOR ENGINEERING SERVICES LTD. OR ITS EMPLOYEES

ACCEPT LIABILITY OR WARRANTY THE WORK WITH RESPECT

TO THE EFFECT OF SETTLEMENT ON THE CIVIL WORKS.

SEE ARCHITECTURAL DRAWINGSFOR BUILDING DETAILS

POST-DEVELOPMENT IRMP SOURCE CONTROL SUMMARY:IRMP CRITERIA:1. RUNOFF VOLUME REDUCTION : RETAIN THE FIRST 24mm OF RAINFALL IN

24-HOURS, AS PER CoV RAINWATER MANAGEMENT BULLETIN (JULY 2018)

TOTAL RAINFALL TARGET FOR CAPTURE = 1608m² x 24mm = 38.59m³

TIER 1 - ONSITE RAINWATER HARVESTING:

SINCE THE BUILDING FOUNDATION WILL COVER THE ENTIRE EXTENTS OF THESITE, INFILTRATION INTO IN SITU SOILS IS NOT POSSIBLE. THEREFORE, TIER 1STRATEGIES COULD NOT BE USED FOR THIS DEVELOPMENT.

TIER 2 - ONSITE RAINWATER RETENTION:

THE SITE HAS OPPORTUNITIES FOR ABSORBENT LANDSCAPED AREAS ONGROUND LEVEL, ROOF AND OVERHANG.

1) GROWING MEDIUM, ASSUMING 20% RETENTION CAPACITY: 390.77m³ x 20% = 78.15m³

WATER RETENTION CAPACITY:

2) TOTAL RAINFALL ON HARD LANDSCAPED AREA NOT DRAINED TO SOFT LANDSCAPE AREA (ROOF) = 636.44m² X 24mm RAIN = 15.27m³

THEREFORE, DETENTION TANK SIZE REQUIRED= 15.3m³REQUIRED FLOW RATE= 3.6 l/sec = 0.0036 m³/sec

2. RELEASE RATE: POST DEVELOPMENT PEAK RELEASE RATE MUST EQUAL ORBE LESS THAN THE PREDEVELOPMENT PEAK RUNOFF RATE

PREDEVELOPMENT 10-YEAR STORM (2014 IDF) RUNOFF RATE = 28.93 l/sec =0.02893m³/secPOST DEVELOPMENT 10-YEAR (2100 IDF) PEAK RUNOFF RATE = 30.02 l/sec =0.03002m³/secREQUIRED STORAGE TO PROVIDE A RELEASE RATE OF 28.93 l/sec = 0.33m³(MODIFIED RATIONAL METHOD)

DETENTION TANK WILL BE PROVIDED AT BASEMENT LEVEL. A FLOW CONTROLORIFICE SIZED TO RELEASE 0.0036m³/sec WILL BE INSTALLED TO ENSURE THEPROPER DETENTION VOLUME IS PROVIDED. DETAILS ON THE FLOW CONTROLMANHOLE WILL BE PROVIDED AT DETAILED DESIGN STAGE.

2. WATER QUALITY: REMOVE 80% TSS FROM THE FIRST 48mm OF RAINFALL OVERHIGHLY POLLUTED SURFACES INCLUDING DRIVEWAYS AND PARKING, AND24mm OVER ALL OTHER SITE SURFACES. SOME TREATMENT WILL BE PROVIDEDBY THE GROWING MEDIUM. THE REMAINING TREATMENT WILL BE PROVIDEDWITH A TREATMENT SYSTEM. DETAILS OF THE TREATMENT SYSTEM WILL BEPROVIDED AT DETAILED DESIGN STAGE.

PLOT DATE: March 9, 2021

SCALE START DATE

DRAWN BY DESIGN BY

CHECKED BY APPROVED BY

DWG. NO.

REV.

DESIGN NO.

DESTROY ALL PRINTS BEARING PREVIOUS NO.

VECTOR JOB NO. CLIENT

SWM2OF2

OUT LINE OF ROOFAREA = 688.3m²

PROPERTY LINESITE AREA = 1608m²

DETENTION TANK TOPROVIDE MIN 15.3m³DETENTION VOLUME.DETAILS WILL BEPROVIDED AT DETAILDESIGN STAGE.

STORM TREATMENTSYSTEM TO REMOVEMINIMUM 80% TSS.DETAILS WILL BEPROVIDED AT DETAILEDDESIGN STAGE.

FLOW CONTROLMANHOLE TO PROVIDE AMAX 3.608L/sec RELEASERATE. DETAILS WILL BEPROVIDED AT DETAILEDDESIGN STAGE

PROP. 5.3m 200Ø PVCSDR35 STM CONN AT 2%,C/W I.C. AT PL.INV. AT PL = 33.48m (CALCFROM GIS)TIE TO EX 200Ø STM SEWER

1065 HARWOOD STREET / 1332THURLOW STREET (NORTH TOWER)

VANCOUVER, BC

DATUM-GEODETICBENCHMARK: MON. V-3508 ATHARWOOD ST AND BUTE STELEV = 27.850m CVD28GVRD DATUM

SITE CATCHMENTAREAS

IMPERVIOUSRATIO

72%POST-DEVELOPMENT

78%PRE-DEVELOPMENT

PERVIOUSRATIO

28%

22%

SOFT LANDSCAPING - LEVEL 1

SOFT LANDSCAPING - ROOF

SITE CATCHMENT AREA BOUNDARY

DIRECTION OF FLOW

SOFT LANDSCAPING - OVERHANG

APPENDIX 3

HYDROGRAPHS PRE & POST DEVELOPMENT

VESL-2513 - Preliminary IRMP Location: 1065 Harwood 1332Thurlow (North Tower)

0.000

5.000

10.000

15.000

20.000

25.000

30.000

35.000

0 10 20 30 40

Flo

w R

ate

(LP

S)

Time Duration (min.)

Hydrograph

Tr=Tc Flow (LPS)

Peak Flow [Post] (LPS)

Max Release Rate Qrel (LPS)

-0.050

0.000

0.050

0.100

0.150

0.200

0.250

0.300

0.350

0.400

0 10 20 30 40 50 60 70

Vo

lum

e (

cub

ic m

ete

r)

Time (minutes)

Required Storage Volume

Required Storage Volume (cm)

2021-03-11

VESL-2513 - Preliminary IRMP Location: 1065 Harwood 1332Thurlow (North Tower)

Max Release Rate Qrel (LPS)

y = 23.56x-0.548

R² = 1

0.0

5.0

10.0

15.0

20.0

25.0

0 5 10 15 20 25 30

Rai

nfa

ll In

ten

sity

(m

m/h

r)

Duration (Hr)

CoV 2014 IDF-5 Yr Return (mm/hr)

Rainfall Intensity (mm/hr)

y = 26.43x-0.542

R² = 1

0.0

5.0

10.0

15.0

20.0

25.0

30.0

0 5 10 15 20 25 30

Rai

nfa

ll In

ten

sity

(m

m/h

r)

Duration (Hr)

CoV 2100 IDF-5 Yr Return (mm/hr)

Rainfall Intensity(mm/hr)

2021-03-11

APPENDIX 4

LANDSCAPING DESIGN AND SOIL LOADING DIAGRAM

THURLOW AND HARWOOD 2

Ground Level Plan

North Tower

CHILDREN’S

PLAY AREA

OUTDOOR

LOBBY

Resting bench

Stormwater infiltration

Water feature

Bike racks

Casual seating

Stormwater runnel water feature

Resting bench

LIN

EA

R G

AR

DE

N

STORMWATER GARDEN

N

THURLOW AND HARWOOD 10

Roof Plan

North Tower

N

N

CONSULTANT

DRAWING TITLE

JOB TITLE

DATE DRAWN

SCALE CHECKED

JOB NO.

ISSUED FOR: DATE

Copyright reserved. The documents and design as an instrumentof service are and at all times remain the exclusive property ofHENRIQUEZ PARTNERS ARCHITECTS and may not bereproduced without the express written consent of HENRIQUEZPARTNERS ARCHITECTS. All designs and related information inwhole or in part shown on these documents are for the express usefor the specified project only and shall not be used otherwisewithout the express written consent of HENRIQUEZ PARTNERSARCHITECTS.

The Contractor shall verify and be responsible for all dimensions onsite and shall inform HENRIQUEZ PARTNERS ARCHITECTS ofany variations from the dimensions and conditions shown on thedocuments. Shop drawings shall be submitted to HENRIQUEZPARTNERS ARCHITECTS for review and approval prior tofabrication.

HENRIQUEZ PARTNERS ARCHITECTS do not warrant that thedrawings are produced to scale. Dimensions may not be scaledfrom the documents.

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Soil Retained Volume

Thurlow and Harwood -

North Site1065 Harwood St/ 1332 Thurlow St

Vancouver, BC

1602

Author

Checker

02/18/21

Soil Volume

Level Type Depth Area Volume

LEVEL 1Generic SoilDepth 900

900 136.46 m² 122.81 m³


1,200 21.36 m² 25.63 m³


600 28.99 m² 17.40 m³


900 53.61 m² 48.25 m³


450 20.73 m² 9.33 m³


900 133.67 m² 120.31 m³


900 3.72 m² 3.34 m³

ROOF LEVELGeneric SoilDepth 450

450 10.43 m² 4.69 m³

ROOF LEVELGeneric SoilDepth 900

900 43.41 m² 39.07 m³

Grand total: 14 452.38 m² 390.83 m³

Documents

(IRMP) H S T ST (NORTH TOWER , VANCOUVER BC