functional servicing and stormwater management …
TRANSCRIPT
1 Issued for Re-Zoning November 16, 2018
No. Revision Date
Prepared For:
Minto Cordova LP
FUNCTIONAL SERVICING AND STORMWATER MANAGEMENT REPORT IN SUPPORT OF RE-ZONING APPLICATION 12, 16, AND 20 CORDOVA AVENUE
City of Toronto
Etobicoke York District
8395 Jane Street, Suite 100 Vaughan, Ontario L4K 5Y2 Tel: (905) 326-1404 File Number: 18056
Minto Cordova LP
12, 16, and 20 Cordova Avenue
Project No.: 18056
November 2018 Page 2
EXECUTIVE SUMMARY This Functional Servicing and Stormwater Management Report has been prepared on behalf of Minto Cordova LP in support of an Official Plan Amendment and Re-Zoning applications, to provide for site specific regulations for the subject site. This Report presents a site servicing strategy for the proposed development that addresses the requirements of the applicable regulatory agencies and provides the basis for detailed servicing design. The servicing strategy for the proposed development is summarized as follows:
WATER SERVICING:
• The proposed development is to be serviced by one (1) connection to the existing 300 mmø watermain located on Cordova Avenue. The water demand requirement of the proposed development for Maximum Day Demand plus Fire Flow is 8104 L/min. The proposed development results in an increase in Maximum hour and Maximum Day demand. Site specific watermain pressure tests indicate that the existing 300 mmø watermain meets the water demand for the proposed development.
FOUNDATION DRAINAGE:
• The long-term foundation drainage discharge rate is estimated to be 187.4 m3/day (2.17 L/s) for the caisson wall option. A peak flow rate of 75 USgpm (4.73 L/s) has been incorporated into the sanitary analysis. Discharge of foundation drains will be in accordance with Toronto Municipal Code, Chapter 681 Sewers.
• The short-term foundation drainage discharge rate is estimated to be 162.8 m3/day (1.88 L/s) for the caisson wall option. A peak flow rate of 50 USgpm (3.15 L/s) has been incorporated into the sanitary analysis. Discharge of foundation drains will be in accordance with Toronto Municipal Code, Chapter 681 Sewers.
• The quality limits for discharge to the sanitary sewer will satisfy the limits as listed in Table 1 – Limits for Sanitary and Combined Sewer Discharge in both short and long-term scenarios.
SANITARY SERVICING:
• The proposed development is to be serviced by a new sanitary connection to the
existing 450 mmø concrete sanitary sewer located on Cordova Avenue. The estimated
peak sanitary flow of the existing site is 0.24 L/s. The peak sanitary design flow of the proposed development is 11.41 L/s (including anticipated groundwater foundation drainage), which is an 11.17 L/s increase in flow.
• A review of the existing and proposed sanitary sewer system downstream of the site was completed and confirms that there is no surcharging in both dry and wet conditions. As such, no external upgrades are required.
Minto Cordova LP
12, 16, and 20 Cordova Avenue
Project No.: 18056
November 2018 Page 3
STORMWATER SERVICING:
• Under existing conditions the stormwater flows uncontrolled to the existing 600 mmø concrete storm sewer on Cordova Avenue. The proposed development will be serviced by a new storm connection to the existing 600 mmø concrete storm sewer. The City of Toronto’s Wet Weather Flow Management Policy identifies performance objectives for runoff from new development sites including water quantity, quality and water balance.
• Quantity - Quantity control will be provided on-site by approximately 69 m3 of underground storage tank in combination with an inlet control to ensure that the 100-year post development peak flows are attenuated to the 2-year predevelopment allowable release rate to Cordova Avenue.
• Water Balance – A water balance volume of 8.7 m3 is required and will be retained through the re-use of stormwater internally within the building. Details of internal reuse to be provided by the mechanical consultant.
• Quality – Roof and non-vehicular coverage is approximately 89% of the total site area. Runoff from rooftop surfaces and terraces is considered clean discharge and quality control may not be required; however, this will be determined at the time of Site Plan Approval.
Minto Cordova LP
12, 16, and 20 Cordova Avenue
Project No.: 18056
November 2018 Page 4
TABLE OF CONTENTS
EXECUTIVE SUMMARY ...................................................................................... 1
TABLE OF CONTENTS ....................................................................................... 4
List of Figures ..................................................................................................... 5
List of Appendices .............................................................................................. 5
1.0 INTRODUCTION ............................................................................................ 6
1.1 Background .................................................................................................. 6
2.0 STUDY PARAMETERS ................................................................................. 8
3.0 WATER SUPPLY ........................................................................................... 9
3.1 Existing Water Supply ................................................................................. 9
3.2 Proposed Water Supply ............................................................................... 9
4.0 FOUNDATION DRAINAGE ......................................................................... 10
5.0 SANITARY SERVICING .............................................................................. 12
5.1 Existing Sanitary Servicing ....................................................................... 12
5.2 Proposed Sanitary Servicing .................................................................... 12
6.0 STORMWATER SERVICING ...................................................................... 14
6.1 Existing CONDITIONS ................................................................................ 14
6.2 Allowable Release Rate ............................................................................. 16
6.3 Proposed Stormwater Servicing ............................................................... 17
6.4 Quantity Control ......................................................................................... 19
6.5 Water Balance ............................................................................................ 20
6.6 Quality Control ........................................................................................... 21
7.0 CONCLUSIONS ........................................................................................... 22
Minto Cordova LP
12, 16, and 20 Cordova Avenue
Project No.: 18056
November 2018 Page 5
LIST OF FIGURES
Figure 1 Site Location
Figure 2 Existing Storm Drainage
Figure 3 Proposed Storm Drainage
Figure 4 Existing Conditions Sanitary Drainage Area Map (in Appendix C)
Figure 5 Proposed Conditions Sanitary Drainage Area Map (in Appendix C)
LIST OF APPENDICES
Appendix A Topographic Survey, Prepared by R. Avis Surveying Inc.
Site Plan, Prepared by Rafael + Bigauskas Architects
Appendix B Water Demand Calculations
Flow Test Results, Jackson Waterworks
Appendix C Hydroglogical Review, Terraprobe
Sanitary Design Flow Calculations
Sanitary Capacity Analysis, Prepared by Counterpoint Engineering
Appendix D Stormwater Design Calculations
Minto Cordova LP
12, 16, and 20 Cordova Avenue
Project No.: 18056
November 2018 Page 6
1.0 INTRODUCTION
1.1 BACKGROUND
This Functional Servicing and Stormwater Management Report has been prepared on behalf
of Minto Cordova LP in support of an Official Plan Amendment and Re-Zoning Plan Application
Approval for a 0.246 ha site.
The subject site is located within the Etobicoke Centre neighbourhood in the City of Toronto. It
is located on the west side of Cordova Avenue between Islington Avenue and Dundas Street
West. The site is bound by mixed use; commercial and residential lands to the north and west,
a school to the south, and Cordova Avenue to the east. The site is located at the northerly edge
of a large apartment neighbourhood located to the north and west if Islington subway station.
Figure 1 – Site Location illustrates the subject site within the context of its surroundings.
Existing underground servicing infrastructure is available on Cordova Avenue. The 0.246 ha
site is currently occupied by 4 single-family detached dwellings. For the existing conditions a
topographical survey of the site has also been included in Appendix A. The site area
considered accounts for the future widening of the public lane to the north and Cordova Avenue
to the east.
The proposed site development is a twenty seven (27) storey residential building. Refer to
Appendix A for the Site Plan prepared by Rafael + Bigauskas Architects.
This FSR has been prepared to address the site servicing strategy (stormwater, sanitary, and
water) in support of a re-zoning and site plan approval application. The proposed servicing
works (including stormwater conveyance) will be designed to meet City of Toronto Design
Guidelines.
8395 Jane St., Suite 100, Vaughan, ON L4K 5Y2Phone 905.326.1404Fax 905.326.1405
COUNTERPOINT ENGINEERING INC.
SITE LOCATION
MIXED USE - COMMERCIAL RESIDENTIAL
12 - 20 CORDOVA AVENUE
SUBJECT SITE
Minto Cordova LP
12, 16, and 20 Cordova Avenue
Project No.: 18056
November 2018 Page 8
2.0 STUDY PARAMETERS
This servicing assessment is based on the review of the following documents and drawings:
• Architectural Plans prepared by Rafael + Bigauskas Architects
• Hydrological Review prepared by Terraprobe
• Flow Test prepared by Jackson Waterworks
• Plan and Profile Drawings, Cordova Avenue (PSB-473, PDB-1184), provided by City
of Toronto
• Plan and Profile Drawings, Central Park Roadway (PSB-551), provided by City of
Toronto
• City of Toronto Wet Weather Flow Management Guidelines, prepared by City of
Toronto, Revised November 2006
• City of Toronto Sewer Atlas Maps, prepared by City of Toronto, Third Edition January
2010
Minto Cordova LP
12, 16, and 20 Cordova Avenue
Project No.: 18056
November 2018 Page 9
3.0 WATER SUPPLY
3.1 EXISTING WATER SUPPLY
There is an existing 300 mmø watermain on the west side of Cordova Avenue. There is an
existing fire hydrant on Cordova Avenue in front of the site. The existing buildings on-site
appear to have individual connections to the Cordova Avenue watermain.
3.2 PROPOSED WATER SUPPLY
The site will be serviced by one (1) connection to the aforementioned 300 mmø watermain on
Cordova Avenue.
The City of Toronto’s design criteria states that the water demand used for watermain size
selection should be sufficient to satisfy maximum day demand plus fire flow or the peak hour
demand, whichever is greater. Fire flow for residential areas will not be less than 4,800 L/min
for a 2 hour duration in addition to the maximum daily domestic demand, delivered with a
residual pressure of not less than 140 kPa. For commercial, institutional and industrial areas,
the minimum fire flow available will not be less than 5,000 L/min for 4 hours, delivered with a
residual pressure of not less than 140 kPa. Fire demand was calculated as per the Fire
Underwriter’s Survey (FUS) guidelines (1999).
Refer to Appendix B for the supporting calculations of the following proposed flows:
• Maximum Hour Demand = 198 L/min
• Maximum Day Demand = 103 L/min
• Fire Flow Demand (2.0 hours) = 8,000 L/min
• Maximum Day Demand plus Fire Flow Demand = 8,104 L/min (governs)
Minto Cordova LP
12, 16, and 20 Cordova Avenue
Project No.: 18056
November 2018 Page 10
City of Toronto design criteria dictates the following system pressure requirements:
• Average Day and Maximum Day range = 350 kPa to 550 kPa
• Minimum hour and peak hour range = 275 kPa to 700 kPa
• Minimum pressure under any non-fire demand scenario = not less than 275 kPa
• Minimum residual pressure during maximum day plus fire scenarios = not less than
140 kPa
• Maximum static pressure = 690 kPa
A hydrant flow test was completed on October 24, 2018 by Jackson Waterworks. The results
of the flow test are included in Appendix B and indicate there is sufficient pressure and flow to
accommodate the proposed redevelopment. Based on the calculated requirements for the
redevelopment and the test results, no watermain upgrades will be required.
4.0 FOUNDATION DRAINAGE
Discharge of foundation drains to municipal sewers must be in accordance with Toronto
Municipal Code, Chapter 681 Sewers. The quality limits for discharge in the sewers must satisfy
the limits as listed in Table 1 – Limits for Sanitary and Combined Sewer Discharge and/or Table
2 – Limits for Storm Sewer Discharge of Chapter 681. A Permit To Take Water (PTTW) from
the Ontario Ministry of the Environment and Climate Change (MOECC) through an online
process is required for Short Term water taking between 50 m3/day and 400 m3/day. A PTTW
is required for Long Term water taking from a permanent drainage system greater than 50
m3/day. A permit is required from the City of Toronto for both short term and long term
discharges to the municipal sewer system.
A Hydrological Review was prepared by Terraprobe, dated October 23, 2018 for the
proposed development.
Minto Cordova LP
12, 16, and 20 Cordova Avenue
Project No.: 18056
November 2018 Page 11
Short Term (Construction) – Groundwater and 25mm rainfall rates are expected to be 162.8
m3/ day (1.88 L/s or an expected peak pump rate of 3.15 L/s) with the caisson wall option.
A limited PTTW from the MOECC will be required for construction dewatering. Discharge will
be to the 450 mmø sanitary sewer on Cordova Avenue. Temporary discharge must meet
Toronto Table 1 Sanitary/Combined Sewer Discharge Limits prior to discharge to the municipal
sanitary sewer. Details of Construction (short-term) dewatering will be provided by a dewatering
contractor prior to construction that satisfies Toronto Municipal Code, Chapter 681 Sewers in
order to obtain a short-term discharge permit from the City.
Long Term Discharge - The report indicates an estimated long-term discharge rate of 187.4
m3/day (2.17 L/s) with the caisson wall option. However, the sanitary analysis will be based on
the peak pump rate of 25 USgpm (4.73 L/s) discussed later in Section 5.2. An agreement with
the City of Toronto for long term discharge will be required. The report indicates that the
groundwater quality currently meets the Table 1 – Limits for Sanitary and Combined Sewer
Discharge. Details of the treatment system, sub slab foundation system, sump pit sizing, water
meter location and specification and peak flow rates to be provided, by others, at the time of
Long Term Discharge Application. A sampling port will be installed at ground level at the
property line to ensure quality and quantity control is maintained.
Refer to Appendix C for the body of the Terraprobe Hydrogeological Review. As discussed in
Section 5.2, a downstream capacity analysis was completed in post-development conditions
for the municipal sanitary sewer system. The analysis included the peak long-term discharge
and determined there is capacity to accommodate the redevelopment. As the overall discharge
from the site to the sanitary system is lower in the short-term conditions than in post-
development, there is also capacity to accommodate the short-term foundation discharge.
Minto Cordova LP
12, 16, and 20 Cordova Avenue
Project No.: 18056
November 2018 Page 12
5.0 SANITARY SERVICING
5.1 EXISTING SANITARY SERVICING
There is an existing 450mmø sanitary sewer on the west side of Cordova Avenue. The sanitary
sewer flows southerly and outlets to an easterly-flowing sanitary sewer on Central Park
Roadway. The Central Park Roadway sanitary sewer outlets to a trunk sewer within the Mimico
Creek valley east of Islington Avenue. The existing detached dwellings currently on-site are
serviced by the Cordova Avenue sanitary sewer. In existing conditions, it is estimated that the
existing peak sanitary flow from the site to the Cordova Avenue sanitary sewer is approximately
0.24 L/s.
5.2 PROPOSED SANITARY SERVICING
The site will be serviced by a new connection to the existing 450mmø sanitary sewer on
Cordova Avenue.
Using the City of Toronto Sanitary Design criteria the equivalent population for the proposed
residential development is approximately 606 persons. The peak sanitary flow for the
proposed development has been calculated to be 11.41 L/s. This peak flow rate includes the
peak anticipated foundation flow from the permanent drainage system based on an assumed
pump rate of 75 USgpm (4.73 L/s). Refer to Appendix C for detailed calculations. The
proposed development results in an increase of 11.17 L/s in the peak sanitary flow to the
Cordova Avenue sanitary sewer.
A detailed analysis of the sanitary sewer system from upstream of the proposed development
to the aforementioned trunk sewer within the Mimico Creek valley has been completed under
both dry and wet weather flow conditions. The detailed analysis incorporates two new
developments/re-developments within the drainage boundary.
Minto Cordova LP
12, 16, and 20 Cordova Avenue
Project No.: 18056
November 2018 Page 13
The analysis determined that for the proposed development:
• The existing sanitary sewer has capacity to accommodate the dry weather flow without
surcharge;
• The existing sanitary sewer has capacity to accommodate the wet weather flow without
surcharge;
Based on the conclusions in the downstream sewer analysis, no external sanitary sewer
upgrades are required to accommodate the proposed redevelopment. Refer to Appendix C for
the downstream sanitary sewer capacity analysis, and the downstream sanitary maps.
It should be noted that as the short-term/construction discharge rate to the Cordova sanitary
sewer of 3.15 L/s is lower than the long-term rate of 11.41 L/s, there is therefore also capacity
in short-term conditions with no external upgrades required.
Minto Cordova LP
12, 16, and 20 Cordova Avenue
Project No.: 18056
November 2018 Page 14
6.0 STORMWATER SERVICING
6.1 EXISTING CONDITIONS
There is an existing 600 mmø storm sewer on Cordova Avenue adjacent to the site. The storm
sewer on Cordova Avenue conveys flows southerly to a 900 mmø storm sewer on Central Park
Roadway which ultimately outlets to Mimico Creek east of the Central Park Roadway and
Islington Avenue intersection.
Storm runoff discharges overland to the Cordova Avenue road allowance. Refer to Figure 2
for a topographical survey of the existing site conditions. No stormwater management controls
have been identified within the existing site; therefore, it is understood that the site currently
discharges uncontrolled storm runoff as summarized in Table 1.
Table 1 – Existing Site Uncontrolled Runoff
Storm Event Existing Site
Uncontrolled Runoff (L/s)
2-Year 39
5-Year 59
10-Year 72
25-Year 84
50-Year 100
100-Year 111
Refer to Appendix D for storm runoff calculations.
CORDOVA AVENUE
A=C=
0.011SITE
0.90
A=C=
0.012SITE
0.90A=C=
0.009SITE
0.90
A=C=
0.007SITE
0.90
A=C=
0.002SITE
0.90
A=C=
0.013SITE
0.90
A=C=
0.19SITE
0.68
OVERLAND FLOW DIRECTION
DRAINAGE AREA BOUNDARY
AREA ID
AREA (ha)
RUNOFF COEFFICIENT
EXISTING STORM DRAINAGE PLAN
2
18056
N.T.S
NOVEMBER 2018
8395 Jane St., Suite 100, Vaughan, ON L4K 5Y2Phone 905.326.1404
Fax 905.326.1405
COUNTERPOINT ENGINEERING INC.
A=C=
0.15SITE
0.55
12, 16, 18 & 20 CORDOVA AVENUE
PROPOSED MIXED USED COMMERCIAL &
RESIDENTIAL DEVELOPMENT
Minto Cordova LP
12, 16, and 20 Cordova Avenue
Project No.: 18056
November 2018 Page 16
6.2 ALLOWABLE RELEASE RATE
The sites imperviousness under existing conditions is greater than 50%. Under Toronto’s Wet
Weather Flow Management Guidelines (WWFMG), the maximum value of C (Runoff
Coefficient) used in calculating the pre-development peak runoff rate is limited to 0.50, in this
condition this criteria applies.
The allowable release rate for the 0.246 ha site area was determined by calculating the 2-year
peak flow with a composite runoff coefficient of 0.50. As a result, the allowable discharge from
the subject site is calculated as follows:
QA = C x A x i x N (l/s)
Table 2 - Allowable Release Rate
Variables Site
A - Site Area (ha) 0.246
Tc (min) 10
C - Runoff Coefficient 0.28
i - Intensity 88.19
N – Constant 2.778
Q - Release Rate (l/s) 30.1
Quantity control will be provided on-site to ensure that the 100-year post development peak
flows to the 600 mmø Cordova Avenue storm sewer will be attenuated to the 2-year allowable
release rate of 30.1 L/s as show in Table 2 above. Refer to Appendix D for allowable release
rate calculations.
Minto Cordova LP
12, 16, and 20 Cordova Avenue
Project No.: 18056
November 2018 Page 17
6.3 PROPOSED STORMWATER SERVICING
This report has been prepared in accordance with the criteria set by the City of Toronto Weather
Flow Management Guidelines (WWFMG). The site will be serviced by the 600 mmø storm
sewer on Cordova Avenue.
Under proposed conditions the building and pedestrian areas comprises approximately 88% of
the 0.246 ha site. An area of approximately he 0.030 ha area along the site frontage and
adjacent to the public lane flows uncontrolled to the Cordova Avenue road allowance. Refer to
Figure 3 – Proposed Storm Drainage.
MPH
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PRIVA
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THE 1
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THE 2
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0.00m
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MPH
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0.00m
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GARB
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HE 5T
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A=C=
0.069G ROOF
0.45
A=C=
0.061NG ROOF
0.90
A=C=
0.116100
0.90
N.T.S
8395 Jane St., Suite 100, Vaughan, ON L4K 5Y2Phone 905.326.1404Fax 905.326.1405
COUNTERPOINT ENGINEERING INC.
PROPOSED SWM PLAN
3
A=C=
0.15SITE
0.55
NOVEMBER 2018
12, 16, 18 & 20 CORDOVA AVENUE
PROPOSED MIXED USED COMMERCIAL &
RESIDENTIAL DEVELOPMENT
Minto Cordova LP
12, 16, and 20 Cordova Avenue
Project No.: 18056
November 2018 Page 19
6.4 QUANTITY CONTROL
The allowable site release rate for the proposed development was determined by calculating
the 2-year peak flow with a maximum value of 50% impervious as per the City of Toronto Wet
Weather Flow Management Guidelines. Based on the above, the allowable release rate to the
600 mmø Cordova Avenue storm sewer was calculated to be 30.1 L/s.
The uncontrolled area (UNC) discussed in Section 6.3 will produce a peak runoff of 16.8 L/s
during the 100-year storm event.
Quantity control will be provided on-site by an underground storage tank within the P1 level of
the building in combination with an inlet control device to ensure that the 100 year post
redevelopment peak flows from the site are attenuated via an orifice control to the 2 year
allowable release rate of 30.1 L/s. A storage volume of approximately 69 m3 will be required to
control the 100-year post development flows to the orifice release rate. Note that an additional
8.7 m3 volume will be available for the water reuse cistern portion of the tank. Refer to
Appendix D for detailed calculations.
Table 3 – Peak Flow and Storage Summary - 100-Year Storm Event
Area ID Area (ha) Runoff
Coefficient
tc (min)
Storage Available
(m3)
Storage Required
(m3) Release
Rate (L/s) Description Orifice
Size (mm)
Release Rate (L/s)
Uncontrolled 0.030 0.81 10 0 N/A 16.8
Uncontrolled to Cordova
Avenue - -
SITE 0.233 0.90 10 0 74 13.3 Orifice Plate At SPA
TOTAL 0.246 0 74 30.1
1. On-site storage will be provided via an underground storage tank located within the building. 2. Refer to Appendix D for modified rational calculations.
As shown in Table 3 above, the proposed site release rate of 30.1 L/s during the 100-year
storm event will be equal to the allowable release rate of 30.1 L/s. Refer to Appendix D for
storage volume calculations.
In situations where the orifice control is not sufficient, the at grade access lid to the underground
storage tank will allow water to discharge overland to Cordova Avenue. The access lid is to be
Minto Cordova LP
12, 16, and 20 Cordova Avenue
Project No.: 18056
November 2018 Page 20
as per OPSD 401.010 – Type B – Open Cover. The required water reuse volume will be
available below the outlet invert and is discussed in further detail later in this report in Section
6.6.
The design of all internal piping within the building must provide adequate capacity for full
capture and conveyance of all flows generated by storms up to and including the 100-year
rainfall event. All design and associated calculations for the internal storm system, including
the design of the internal inlet structures, piping and mechanical appurtenances is to be
completed by the Mechanical Engineer.
6.5 WATER BALANCE
The Wet Weather Flow Guidelines indicate that the minimum on-site runoff retention requires
the proponent to retain all runoff from a small design rainfall event – typically 5 mm (In Toronto,
storms with 24 hour volumes of 5 mm or less contribute about 50% of the total average annual
rainfall volume).
To achieve the water balance objectives, the site was categorized by surface types: impervious
asphalt/paved/roof, landscaped areas and conventional roof. The initial abstraction values for
the impervious surfaces and pervious surfaces were 1 mm and 5 mm, respectively. The initial
abstraction was determined based on percent of surface area and initial abstraction values of
each surface type. Based on the site area of 0.246 ha, a 5 mm - 24 hour storm is equivalent to
approximately 12.3 m3 of total site storage (2456 m2 x 0.005 m). Without any specific on-site
retention measures, the proposed development would achieve the following levels of water
balance as seen in Table 5.
Minto Cordova LP
12, 16, and 20 Cordova Avenue
Project No.: 18056
November 2018 Page 21
Table 5 – Achieved Water Balance
Site Description Fraction of Site Area Initial
Abstraction (mm)
Overall Initial Abstraction
(mm)
Non-Green Roof Building Area 54% 0.134 ha 1.0 0.55
Asphalt Impervious Area 33% 0.082 ha 1.0 0.33
Pervious / Green Roof Area 12% 0.030 ha 5.0 0.61
Total 100% 0.246 ha 1.49 *Fraction of Site Area does not add to 100% due to rounding
Based on Table 5, the site will have a shortfall of 3.51 mm (5 mm – 1.49 mm) of initial
abstraction. This is equivalent to approximately 8.7 m3 of storage. To achieve water balance
requirements, a water re-use system will be employed to provide the additional storage
indicated above.
The re-use storage tank will form part of the underground stormwater storage tank provided for
quantity control. The underground storage tank will outlet at an elevation such that 8.7 m3 will
be available below the outlet invert for re-use.
6.6 QUALITY CONTROL
The Wet Weather Flow Management Guidelines stipulate that 80% removal of TSS is required
on an average annual loading basis from all runoff leaving the proposed development.
As a large portion of the site consists of roof, landscape, and non-vehicular impervious areas,
all of which are free of oil and grit, quality control measures may not be required. However, the
implementation of Oil-Grit Separators (OGS) or other quality control measures will be
investigated during the Site Plan Approval stage of the development to determine if they are
needed once the site plan has been finalized. Exact details on any quality control units will be
described as part of a Stage-2 Stormwater Management Report.
Minto Cordova LP
12, 16, and 20 Cordova Avenue
Project No.: 18056
November 2018 Page 22
7.0 CONCLUSIONS
This Functional Servicing Report presents a site servicing strategy for the proposed
development that addresses the requirements of the applicable design guidelines and provides
the basis for detailed servicing design.
The existing municipal infrastructure for water distribution, sanitary sewers, and storm sewers
can adequately accommodate the proposed redevelopment with no adverse impacts to the
system.
We trust this report sufficiently addresses the site servicing requirements and allows for
approval of the proposed Official Plan Amendment and Re-Zoning and site plan approval of
the subject site for the proposed use described herein. Should there be any questions or
comments, please feel free to contact the undersigned.
Sincerely,
Counterpoint Engineering Inc.
Rasheed Serrao, P.Eng. 905-326-3169 [email protected]
Project No.: 18056
November 2018
Minto Communities
12-20 Cordova Avenue
Appendix A
Project No.: 18056
November 2018
Minto Communities
12-20 Cordova Avenue
Appendix B
Counterpoint Engineering Inc.Water Demand Design Calculations
Project: 12-20 Cordova Avenue
Project No: 18056
Location: Toronto, Ontario
Site Area: 0.246 ha
Population
1BR/1BR+Den 1.4 ppu
2BR/2BR+Den/ 2.1 ppu
3BR/3BR+Den 3.1 ppu
Commercial / Retail 1.1 persons/100m2
Offices 3.3 persons/100m2
1B / 1B+D 2B / 2B + D 3B / 3B+D Total Units Area (m2)
Level 1 - 27 164 131 32 327 25,720
TOTAL UNITS / AREA (m2) 164 131 32 327 25,720
Population 1BR
/ 1B + D
Population
2BR / 2BR +
D
Population
3BR / 3BR +
D
TOTAL
POPULATION
Residential 230 276 100 606
Total Equivalent Population 606
City of Toronto Watermain Guidelines
Per Capita Demand
Single Family 320 (l/capita/day)
Multi-Unit 191 (l/capita/day)
Peaking Factors
Land Use Minimum Hour Maximum Hour Maximum Day
Residential 0.70 2.48 1.65
Commercial 0.84 1.20 1.10
Industrial 0.84 0.90 1.10
Institutional 0.84 0.90 1.10
Apartment 0.84 2.50 1.30 *Values used for Residential (Multi-Unit) Land Use
Water Demand based on Equivalent Population
Land Use PopulationMinimum Hour
(l/min)
Maximum
Hour
(l/min)
Maximum
Day
(l/min)
Fire Flow
Required
(l/min)
Fire Flow
Duration (hr)*
Max Day +
Fire Flow
(l/min)Residential (Multi-Unit) 606 67.5 200.9 104.5 - - -
Totals 606 67.5 200.9 104.5 8000 2.00 8104
* See attached table in Appendix B for Fire Flow Duration
Residential Units
Counterpoint Engineering Inc.
REQUIRED FIRE FLOW WORKSHEET - PROPOSED DEVELOPMENT
Fire Underwriters Survey
Project : 12-20 Cordova Avenue
Project No: 18056
Guide for Determination of Required Flow Copyright I.S.O
Class Factor
WF Wood Frame 1.5
OC Ordinary Construction 1.0
NC Non-Combustible 0.8
FC Fire-Resistive 0.6
% Reduction
NC Non-Combustible 25
LC Limited Combustible 15
C Combustible 0
FB Free Burning 15
RB Rapid Burning 25
1) Fire Flow
Type of Construction: NC
C= 0.8
A*= 1955 m2
F= 7,781 L/min
2) Occupancy Reduction/Surcharge
Contents Factor: LC
Reduction/Surcharge of -15% = -1,167 L/min
F= 7781L/min + -1167 L/min = 6,614 L/min
3) System Type Reduction
NFPA 13 Sprinkler: YES 30%
Standard Water Supply: YES 10%
Fully Supervised: NO 0%
Total 40%
Reduction of 40% L/min = 2,646 L/min
F= 6614L/min - 2,646 L/min = 3,969 L/min
4) Separation Charge
Building Face Dist(m) Charge
North 15 15%
East 25 10%
South 15 15%
West 14 15%
Total 55% of 6614.2 L/min = 3,638 L/min
(max exposure charge can be 75%)
F= 3969L/min + 3638L/min = L/min (2,000L/min<F<45,000L/min)
F= L/min (round to the nearest 1,000L/min)
F= L/s
F= gpm
7,606
8,000
133
2,113
Type of Construction
Contents
Note: Assuming non-combustible building. Assuming Vertical Openings are adequately protected.
Area is the total of the largest floor (3rd Floor) plus 25% of the next 2 adjoining floors above.
Counterpoint engineering
NFPA Theoretical Flow Calculations
Project Name: 12-20 Cordova Avenue
Project Number: 18056
QF = 29.83 x c x d2 x p
0.5, where
QF = observed flow (US GPM)
c = hydrant nozzle coefficient (0.90 - 0.95)
d = nozzle diameter (in)
p = observed pitot pressure
QR = QF x hF0.54
/ hR0.54
, where
QR = available flow
QF = observed flow (US GPM)
hF = drop from measured static to desired baseline pressure
hR = drop from measured static to measured residual pressure
Based on flow test results obtained by Jackson Waterworks on October 24, 2018
c = 0.9
d = 2.5 in
number of ports = 2
p = 38
QF = 2069 US GPM
Measured Static Pressure = 80 psi
Measured Residual Pressure = 68 psi
Desired Residual Pressure = 20 psi , minimum per City of Toronto design criteria
QR = 4933 US GPM per fire conneciton
18,675 L/min
Based on National Fire Protection Association Guidelines, the available flow at the minimum residual pressure of
20psi can be calculated based on the observed flow at the observed pressure readings, as follows:
Project No.: 18056
November 2018
Minto Communities
12-20 Cordova Avenue
Appendix C
TerraprobeConsulting Geotechnical & Environmental Engineering
Construction Materials Inspection & Testing
Terraprobe Inc. Greater Toronto Hamilton – Niagara Central Ontario Northern Ontario 11 Indell Lane 903 Barton Street, Unit 22 220 Bayview Drive, Unit 25 1012 Kelly Lake Rd., Unit 1
Brampton, Ontario L6T 3Y3 Stoney Creek, Ontario L8E 5P5 Barrie, Ontario L4N 4Y8 Sudbury, Ontario P3E 5P4
(905) 796-2650 Fax: 796-2250 (905) 643-7560 Fax: 643-7559 (705) 739-8355 Fax: 739-8369 (705) 670-0460 Fax: 670-0558
www.terraprobe.ca
HYDROGEOLOGICAL REVIEW 12, 16, 18 AND 20 CORDOVA AVENUE
TORONTO, ONTARIO M9A 2H5
Prepared for: Minto Cordova LP
4101 Yonge Street, Suite 600 Toronto, Ontario M2P 1N6
Attention:
Mr. Frank Paglucia
File No 1-17-0848-46
October 23, 2018
©Terraprobe Inc.
Hydrological Review October 23, 2018 12, 16, 18 and 20 Cordova Avenue, Toronto, Ontario File No. 1-17-0848-46
Terraprobe Page No. i
EXECUTIVE SUMMARY Terraprobe Inc. (Terraprobe) was retained by Minto Cordova LP to conduct a Hydrogeological Review for the proposed
redevelopment of municipal addresses 12, 16, 18 and 20 Cordova Avenue in Toronto, Ontario (the “Site”).
The conclusions of Terraprobe’s investigation are as follows:
Current Development
Development Phase Above Grade
Levels
Below Grade Levels
Level # Lowest Finished Floor Approximate
Base of Footings (masl) Depth (m) Elevation (masl)
Residential Dwellings 2-3 1 1.5-2 122 Unknown
Proposed Development
Development Phase Above Grade
Levels
Below Grade Levels
Level # Lowest Finished Floor Approximate
Base of Footings (masl) Depth (m) Elevation (masl)
Single Phase 27 P5 15 109.5 108.0
In general, four main stratigraphic units were encountered at the Site which consisted of:
Site Stratigraphy
Stratum/Formation Depth Range (mbgs) Elevation Range (masl) Hydraulic Conductivity (m/s)
Earth Fill 0 to 1.5 124.8 to 122.5 1.0 x 10-6***
Upper Sands and Silts 1.5 to 16.3 123.4 to 108.2 3.65 x 10-7*
Sandy Silt (Till) with Gravel 13.7 to 22.9 110.9 to 101.7 2.01 x 10-6*
*Indicates conductivity was calculated by Slug Test
**Indicates conductivity was estimated using grain size analysis
***Indicates conductivity was estimated using typical published values from Freeze and Cherry (1979)
The ground water conditions at the Site are as follows:
Ground Water Conditions
Ground Water Elevation (masl) 120.5 masl
Zone of Influence (m) 45 m
Ground Water Quality
Sample ID City of Toronto Storm
Sewer Limits City of Toronto Sanitary and
Combined Sewer Limits
Untreated Ground Water (SW-UF) Exceeds Meets
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Terraprobe Page No. ii
Ground Water Control
The water taking requirements for ground water control at the Site are:
Ground Water Quantity: Short Term (Construction) – S.F. 1.25 Used
Location Ground Water Seepage 25mm Design Rainfall Event Total Volume
L/day L/min L/day L/min L/day L/min
Total Site, Permeable
Shoring 320,000 222.2 72,800 50.6 392,800 272.8
Total Site, Caisson Wall
Shoring 90,000 62.5 72,800 50.6 162,800 113.1
Ground Water Quantity: Long Term (Post Construction) – S.F. 1.25 Used
Location Ground Water Seepage
Infiltration 25mm Design Rainfall Event
Total Volume
L/day L/min L/day L/min L/day L/min
Total Site, Drained
Foundation 285,000 197.9 2,400 1.7 287,400 199.6
Total Site, Drained
Foundation with Degraded Caisson Wall
185,000 128.5 2,400 1.7 187,400 130.1
Regulatory Requirements
Environmental Activity and Sector Registry (EASR) Posting
Required for both shoring systems
Short Term Permit to Take Water (PTTW) Not Required for both shoring systems
Long Term Permit to Take Water (PTTW) Required for both shoring systems
Short Term Discharge Agreement City of Toronto Required for both shoring systems
Long Term Discharge Agreement City of Toronto Required for both shoring systems
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Terraprobe Page No. iii
TABLE OF CONTENTS
SECTION PAGE 1.0 Introduction/background ........................................................................................................................................... 1
2.0 Study Area Map ........................................................................................................................................................ 3
3.0 Geology and Physical Hydrology ............................................................................................................................. 4
4.0 Wells ......................................................................................................................................................................... 4
5.0 Static Water Level Analysis ...................................................................................................................................... 5
6.0 Hydrogeolgical Testing ............................................................................................................................................. 5
6.1 Pump Test ............................................................................................................................................................. 5
6.2 Slug Test ............................................................................................................................................................... 6
6.3 Estimation from Gain Size .................................................................................................................................... 6
6.4 Estimation from Literature .................................................................................................................................... 7
7.0 Water Quality ............................................................................................................................................................ 7
8.0 Proposed Consruction methods ................................................................................................................................. 8
9.0 Groundwater Extraction and Discharge .................................................................................................................... 8
10.0 Private Water Drainage System (PWDS) ................................................................................................................ 10
11.0 Zone of Influence (ZOI) .......................................................................................................................................... 10
12.0 Evaluation of Impact ............................................................................................................................................... 11
12.1 City's Sewage Works .......................................................................................................................................... 11
12.2 Negative Impacts to the Natural Environment .................................................................................................... 11
12.3 Local Wells and Zone of Influence ..................................................................................................................... 11
12.4 Contamination Sources ....................................................................................................................................... 11
12.5 Impacts to Land Stability .................................................................................................................................... 12
13.0 Proposed Mitigation Measures and Monitoring Plan .............................................................................................. 12
14.0 Limitations .............................................................................................................................................................. 13
15.0 closure ..................................................................................................................................................................... 13
FIGURES: Figure 1 Site Location Map
Figure 2 Borehole and Monitoring Well Location Plan (Existing Conditions) Figure 3 Hydrological cross-section A-A’
APPENDICES: Appendix A Borehole Logs Appendix B Grain Size Analysis Appendix C Aquifer Response Tests Appendix D Finite Element Model
Appendix E Laboratory Certificate of Analysis Appendix F Ground Water Levels
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Terraprobe Page No. 1
1.0 INTRODUCTION/BACKGROUND
Terraprobe Inc. (Terraprobe) was retained by Minto Cordova LP to conduct a Hydrogeological Review for the proposed
redevelopment of 12, 16, 18 and 20 Cordova Avenue in Toronto, Ontario (the “Site”).
Property Information
Location of Property 12, 16, 18 and 20 Cordova Avenue
Ownership of Property
12 Cordova Avenue: 2598325 Ontario Inc.; Minto Acquisition Limited Partnership
16 Cordova Avenue: 2598325 Ontario Inc.; Minto Acquisition Limited Partnership
18 – 20 Cordova Avenue: 2598325 Ontario Inc.; Minto Acquisition Limited Partnership
Property Dimensions (m) Approximately 52 m by 56 m
Property Area (m2) Approximately 2,912 m2
Existing Development
Number of Building Structures Four (4)
Number of Above Grade Levels Two (2) to Three (3)
Number of Underground Levels One (1)
Sub-Grade Depth of Development (m) 1.5-2 m
Sub-Grade Area (m2) Approximately 750 m2
Land Use Classification Residential
Proposed Development
Number of Building Structures One (1)
Number of Above Grade Levels Twenty-seven (27)
Number of Underground Levels Five (5)
Sub-Grade Depth of Development (m) Approximately 15 m
Sub-Grade Area (m2) Approximately 2,054 m2
Land Use Classification Residential
Hydrological Review October 23, 2018 12, 16, 18 and 20 Cordova Avenue, Toronto, Ontario File No. 1-17-0848-46
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Qualified Person and Hydrogeological Review Information
Qualified Person Matthew J. Bielaski, P.Eng., QPRA
Consulting Firm Terraprobe Inc.
Date of Hydrogeological Review October 23, 2018
Scope of Work
Review of MOECC Water Well Records for the area
Review of geological information for the area
Review of topographic information for the area
Advanced one (1) borehole to a depth of 1.8 m, which was instrumented with a monitoring well
Advanced one (1) borehole to a depth of 2.6 m, which was instrumented with a monitoring well
Advanced one (1) borehole to a depth of 8.2 m, which was instrumented with a monitoring well
Advanced one (1) borehole to a depth of 9.8 m, which was instrumented with a monitoring well
Advanced one (1) borehole to a depth of 17.4 m, which was instrumented with a monitoring well
Advanced one (1) borehole to a depth of 17.6 m, which was instrumented with a monitoring well
Advanced one (1) borehole to a depth of 18.4 m, which was instrumented with a monitoring well
Advanced one (1) borehole to a depth of 18.6 m, which was instrumented with a monitoring well
Advanced one (1) borehole to a depth of 19.5 m, which was instrumented with a monitoring well
Advanced one (1) borehole to a depth of 22.4 m, which was instrumented with two (2) monitoring wells (nested pair at 10.6 m and 22.4 m)
Advanced one (1) borehole to a depth of 23.0 m, which was instrumented with two (2) monitoring wells (nested pair at 7.6 m and 22.7 m)
Advanced one (1) borehole to a depth of 23.3 m, which was instrumented with a monitoring well
Completion of a 24-hr pump test
Completion of slug tests in several representative monitoring wells
Ground water elevation monitoring, every two weeks for a period of 3 months
Ground water sampling and analysis to the City of Toronto Sewer Use Limits
Assessment of ground water controls and potential impacts
Report preparation
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Terraprobe Page No. 3
2.0 STUDY AREA MAP
As per the requirements of the City of Toronto, a map has been provided (Figure 1 and 2) which shows the locations of
the following:
1. All monitoring wells identified on-site
2. All monitoring wells identified off-site within the study area
3. All boreholes identified on-site
4. All buildings identified on site and within the study area
5. The property boundaries of the site
6. Any watercourses and drainage features within the study area.
Hydrological cross-sections with geology, borehole locations and water level measurements are provided on Figure 3.
General Hydrogeological Characterization
Site Topography Approximately 124.5 masl and slopes from north to south.
Local Physiographic Features The overburden consists of coarse-textured glaciolacustrine deposits consisting of sand, gravel, minor silt and clay.
Regional Physiographic Features
The West St Lawrence Lowland consists of a limestone plain (elevation 200–250 masl) that is separated by a broad, shale lowland from a broader dolomite and limestone plateau west of Lake Ontario. This plateau is bounded by the Niagara Escarpment.
From the escarpment the plateau slopes gently southwest to lakes Huron and Erie (elevation 173 masl). Glaciation has mantled this region with several layers of glacial till (i.e., an unsorted mixture of clay, sand, etc.), the youngest forming extensive, undulating till plains, often enclosing rolling drumlin fields.
Surface Drainage South
Ground Water Flow Direction East/Southeast
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Terraprobe Page No. 4
3.0 GEOLOGY AND PHYSICAL HYDROLOGY
The site stratigraphy, including soil materials, composition and texture are presented in detail on the borehole logs in
Appendix A. In general, stratigraphic units that were encountered at the Site consisted of the following:
Site Stratigraphy
Stratum/Formation Aquifer or Aquitard Depth Range (mbgs) Elevation Range
(masl) Thickness (m)
Earth Fill Aquifer 0 to 1.5 124.8 to 122.5 1.5
Upper Sands and Silts Aquifer 1.5 to 16.3 123.4 to 108.2 14.8
Sandy Silt (Till) with Gravel
Aquifer 13.7 to 22.9 110.9 to 101.7 9.2
Bedrock Environment
Stratum/Formation Depth Range (mbgs) Elevation Range (masl) Thickness (m)
Weathered 22.8 101.7 -
Surface Water
Surface Water Body Distance from Site (m) Hydraulically Connected to Site (yes/no)
Mimico Creek Approximately 300 m east No
4.0 WELLS
The following monitoring wells were installed at the site as part of the hydrogeological review.
Well ID Well Dia
(mm)
Ground Surface (masl)
Top of Screen Bottom of Screen Screened Geological
Unit Depth (m) Elev. (masl) Depth (m) Elev. (masl)
BH1 50 125.0 12.2 112.8 15.2 109.8 Sandy Silt
BH2 50 124.5 6.1 118.4 9.1 115.4 Sandy Silt
BH3 50 124.8 4.6 120.2 7.6 117.2 Gravelly Sand
BH101 50 124.7 19.5 105.2 22.6 102.2 Sand and Silt (Till)
BH201-S 50 125.0 4.6 120.4 7.6 117.4 Sand
BH201-D 50 125.0 19.8 105.2 22.9 102.1 Sand and Gravel (Till)
BH202 50 124.6 13.9 110.7 16.9 107.7 Gravelly Sand (Till)
BH203 50 124.9 15.2 109.7 18.3 106.6 Sandy Silt (Till) & Sand and Silt
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Terraprobe Page No. 5
Well ID Well Dia
(mm) Ground Surface Top of Screen Bottom of Screen
Screened Geological Unit
BH204 50 125.0 15.1 109.9 18.1 106.9 Sandy Silt (Till) & Silty Sand (Till)
BH205 50 125.6 15.1 110.5 18.1 107.5 Sandy Silt & Sandy Silt (Till)
BH301 50 122.2 0.6 124.2 1.8 123.0 Silty Sand
BH302 50 123.3 1.7 123.0 2.6 122.1 Silty Sand
BH401-S 50 125.4 7.6 117.8 10.7 114.7 Sandy Silt
BH401-D 50 125.4 19.4 106.0 22.4 103.0 Sand and Gravel (Till) & Sand
Additional details of the monitoring well installation are presented on the enclosed borehole logs in, Appendix A.
5.0 STATIC WATER LEVEL ANALYSIS
The ground water elevations were monitored in the installed monitoring wells. The ground water elevations in the
monitoring wells are presented in Appendix F.
6.0 HYDROGEOLGICAL TESTING
6.1 Pump Test
As per the requirements of the City of Toronto Terms of Reference a 24 hour pumping test was attempted at the site. The
goal of a pumping test is to estimate hydraulic properties of an aquifer system which include transmissivity, hydraulic
conductivity (horizontal and vertical) and storativity (storage coefficient). Pumping tests can identify and locate recharge
and no-flow boundaries that may limit the lateral extent of aquifers as well. The pumping test conducted as part of the
hydrogeological review was a constant-rate pumping test in which a control well is pumped at a constant rate and water-
level response (drawdown) is measured in the surrounding observation wells and in the control well. A recovery test is
performed at the end of a pumping test after pumping in the pumped (control) well has ended. Water-level response
(residual drawdown) is measured after pumping has stopped in the surrounding observation wells and in the control well
itself.
The results of the pump tests were analysed using the Theis (1935) solution. The results of the analysis are presented in
Appendix C. The hydraulic properties of the strata applicable to the Site are as follows:
Monitoring Well Well Screen
Elevation (masl)
Screened Geological Unit Transmissivity Hydraulic
Conductivity (m/s)
Storage Coefficient
PW1 112.9-109.8 Sandy Silt & Sandy Silt (Till) 2.86 × 10-5 1.68 × 10-6 3.23 × 10-6
BH1 112.8-109.8 Sandy Silt 1.00 × 10-3 5.88 × 10-5 1.00 × 10-4
BH2 118.4-115.4 Sandy Silt 1.00 × 10-3 5.88 × 10-5 1.00 × 10-4
BH101 105.2-102.2 Sand and Silt (Till) 1.00 × 10-3 5.88 × 10-5 1.00 × 10-4
BH201-D 105.2-102.1 Sand and Gravel (Till) 1.00 × 10-3 5.88 × 10-5 1.00 × 10-4
BH205 110.5-107.5 Sandy Silt & Sandy Silt (Till) 2.09 × 10-4 1.23 × 10-5 3.27 × 10-3
Average 7.06 × 10-4 4.15 × 10-5 6.12 × 10-4
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Terraprobe Page No. 6
6.2 Slug Test
The hydraulic conductivities from the monitoring well were determined based a slug test (single well response test). This
test involves the rapid removal of water or addition of a “slug” which displaces a known volume of water, from a single
well and then monitoring the water level in the well until the well has recovered. The results of the slug tests were
analysed using the Bouwer and Rice method (1976). The results of the analysis are presented in Appendix C.
The hydraulic properties of the strata applicable to the Site are as follows:
Monitoring Well Well Screen Elevation
(masl) Screened Geological Unit
Hydraulic Conductivity (m/s)
BH1 112.8 to 109.8 Sandy Silt 8.84 x 10-7
BH2 118.4 to 115.4 Sandy Silt 3.70 x 10-7
BH202 110.7 to 107.7 Gravelly Sand (Till) 3.75 x 10-7
BH203 109.7 to 106.6 Sandy Silt (Till) &
Sand and Silt 2.01 x 10-6
BH204 109.9 to 106.9 Sandy Silt (Till) & Silty Sand (Till) 1.17 x 10-6
BH401-D 106.0 to 103.0 Sand and Gravel (Till) & Sand 1.72 x 10-7
6.3 Estimation from Gain Size
The hydraulic conductivities of various soil types can also be estimated from the grain size analysis. Allen Hazen derived
an empirical formula for approximating hydraulic conductivity from grain size analyses:
Equation: K = C(D10)2
Where:
C is the Hazen's empirical coefficient, which takes a value between 0.0 and 1.5 (depending on literatures), with an
average value of 1.0. A.F. Salarashayeri & M. Siosemarde give C as usually taken between 1.0 and 1.5.
K is the estimated hydraulic conductivity in cm/s
D10 is the diameter of the 10 percentile grain size of the material in mm
The grain size analysis are provided in Appendix B. The estimated hydraulic conductivity values based upon the
conducted grain size analysis are provided below.
Sample ID D10 Grain Size (mm) Soil Description Estimated Hydraulic Conductivity (m/s)
BH1 SS10 1.75 x 10-2 Sandy silt 3.06 x 10-6
BH1 SS12 2.15 x 10-3 Sandy silt 4.61 x 10-8
BH2 SS7 1.33 x 10-2 Sandy silt 1.77 x 10-6
BH3 SS6 1.91 x 10-2 Gravelly sand 3.65 x 10-6
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Terraprobe Page No. 7
Sample ID D10 Grain Size (mm) Soil Description Estimated Hydraulic Conductivity (m/s)
BH201-D SS7 8.74 x 10-4 Sandy silt (till) 7.64 x 10-9
BH201-D SS8 6.44 x 10-3 Gravelly sand (till) 4.15 x 10-7
BH202 SS6 5.89 x 10-3 Gravelly sand (till) 3.47 x 10-7
BH203 SS7 1.38 x 10-3 Sandy silt (till) 1.90 x 10-8
BH203 SS8 1.59 x 10-2 Sand and silt 2.52 x 10-6
BH204 SS14 2.32 x 10-3 Silty sand (till) 5.38 x 10-8
BH401-D SS16 8.41 x 10-3 Sandy gravel 7.08 x 10-7
6.4 Estimation from Literature
According to Freeze and Cherry (1979), the typical hydraulic conductivity of the strata investigated at the site are:
Soil Unit Estimated Hydraulic Conductivity Range (m/s)
Earth Fill 10-6
Upper Sands and Silts 10-4 to 10-7
Sandy Silt (Till) with Gravel 10-3 to 10-6
7.0 WATER QUALITY
One (1) unfiltered ground water sample was collected by Terraprobe and analyzed by a Canadian laboratory accredited
and licensed by Standards Council of Canada and or Canadian Association for Laboratory Accreditation. The sample was
collected directly from monitoring well BH1 on March 23, 2018.
It is noted that the City of Toronto required that the water quality data must be collected within nine (9) months prior to
the date of submission. If the submission is nine (9) months after the sample collection date noted above, a new ground
water sample will have to be collected.
The sample was analyzed for the following parameters:
City of Toronto Municipal Code Chapter 681 Table 1 – Limits for Sanitary and Combined Sewers Discharge
City of Toronto Municipal Code Chapter 681 Table 2 – Limits for Storm Sewer Discharge
The results of the ground water analysis indicate the following:
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Ground Water Sample (SW-UF) from BH1
The ground water sample exceeded the Limits for Storm Sewer Discharge for the following parameters:
Total Suspended Solids (Limit 15 mg/L, Result 28 mg/L)
Manganese (Limit 0.05 mg/L, Result 0.337 mg/L)
Phosphorous (Limit 0.4 mg/L, Result 2.31 mg/L)
The ground water sample met the Limits for Sanitary and Combined Sewer Discharge for all parameters analyzed.
A true copy of the analysis report, Certificate of Analysis and a chain of custody record for the sample is included
Appendix E.
8.0 PROPOSED CONSRUCTION METHODS
The final shoring system and construction method was unknown. As such, a permeable (i.e. lagging wall) system and a
continuous caisson walls with the toe embedment at an elevation of 104.0 masl into the inferred bedrock was assessed.
For both shoring systems, it was assumed that the proposed structures will consist of drained foundations.
9.0 GROUNDWATER EXTRACTION AND DISCHARGE
Numerical analysis was conducted for both the short term and long term dewatering scenarios. The modeling was
conducted utilizing computer software (Slide 7.014, released March 30, 2016, developed by Rocscience Inc.), utilizing the
finite element modelling method. The finite element model (FEM) for ground water seepage indicates the short term
(construction) and long term (post construction) dewatering requirements as provided below. The finite element model
results are presented in Appendix D.
It is noted that if the excavation is exposed to the elements, storm water will have to be managed. The short term control
of ground water should take into account storm water management from rainfall events. A dewatering system should be
designed to take into account removal of rainfall from the excavation. Volumes for a 25 mm design storm have been
provided in the quantity estimates.
As required by Ontario Regulation 63/16, a plan for discharge must consider the conveyance of storm water from a 100-
year storm. The additional volume that will be generated in the occurrence of a 100-year storm event is approximately
274,000 L.
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Terraprobe Page No. 9
The following should be noted:
The native soils must be dewatered a minimum of 1 m below the footing elevation prior to excavation to
preserve the in situ integrity of the native soils during construction dewatering activities. It is anticipated that the
ground water elevation will rise to the elevation of the subfloor drainage in the event of a drained structure or the
waterproofing in the event of a water tight structure.
The proposed pump schedule for short term construction dewatering has not been completed. As such the actual
peak short term discharge rate is not available at the time of this report.
The proposed pump schedule for long term post construction drainage has not been completed. As such the
actual peak long term discharge rate is not available at the time of this report.
Ground Water Quantity: Short Term (Construction) – S.F. 1.25 Used
Location Ground Water Seepage 25mm Design Rainfall Event Total Volume
L/day L/min L/day L/min L/day L/min
Total Site, Permeable
Shoring 320,000 222.2 72,800 50.6 392,800 272.8
Total Site, Caisson Wall
Shoring 90,000 62.5 72,800 50.6 162,800 113.1
Ground Water Quantity: Long Term (Post Construction) – S.F. 1.25 Used
Location Ground Water Seepage
Infiltration 25mm Design Rainfall Event
Total Volume
L/day L/min L/day L/min L/day L/min
Total Site, Drained
Foundation 285,000 197.9 2,400 1.7 287,400 199.6
Total Site, Drained
Foundation with Degraded Caisson Wall
185,000 128.5 2,400 1.7 187,400 130.1
Regulatory Requirements
Environmental Activity and Sector Registry (EASR) Posting
Required for both shoring systems
Short Term Permit to Take Water (PTTW) Not Required for both shoring systems
Long Term Permit to Take Water (PTTW) Required for both shoring systems
Short Term Discharge Agreement City of Toronto Required for both shoring systems
Long Term Discharge Agreement City of Toronto Required for both shoring systems
Hydrological Review October 23, 2018 12, 16, 18 and 20 Cordova Avenue, Toronto, Ontario File No. 1-17-0848-46
Terraprobe Page No. 10
Water tight structure (structure that has not included a private water drainage system) has not been considered as
part of the proposed development at this time.
On-site containment (infiltration gallery/dry well etc.) has not been considered as part of the proposed
development at this time. In the event that this considered additional work will have to be conducted (i.e.
infiltration testing).
10.0 PRIVATE WATER DRAINAGE SYSTEM (PWDS)
If the proposed development is designed water tight structure, then a private water drainage system will not be required.
However, the structure must then be designed to resist hydrostatic pressure and uplift forces.
If the proposed development is not water tight structure, then a private water drainage system will be required. The total
sub floor drain area will be approximately 2,054 m2 based on the drawings which have been provided to Terraprobe. The
estimated total volume per day from the sub floor drain and the perimeter drains are provided in the previous Section.
If the building is designed with a private water drainage system, the drainage system is a critical structural element, since
it keeps water pressure from acting on the basement walls and floor slab. As such, the sump that ensures the performance
of this system must have a duplexed pump arrangement for 100% pumping redundancy and these pumps must be on
emergency power. The size of the sump should be adequate to accommodate the ground water seepage. It is anticipated
that the seepage can be controlled with typical, widely available, commercial/residential sump pumps.
11.0 ZONE OF INFLUENCE (ZOI)
The Zone of Influence (ZOI) with respect to ground water was calculated based on the estimated ground water taking rate
and the hydraulic conductivity of the unit which water will be taken at the Site.
The ZOI was calculated using the Sichart equation below.
Equation: R0 = 3000*dH*K0.5
Where:
dH is the dewatering thickness (m)
K is the hydraulic conductivity (m/s)
The ZOI with respect to ground water at the Site is:
R0 = 45± m
Hydrological Review October 23, 2018 12, 16, 18 and 20 Cordova Avenue, Toronto, Ontario File No. 1-17-0848-46
Terraprobe Page No. 11
12.0 EVALUATION OF IMPACT
12.1 City's Sewage Works
Negative impacts to City's sewage works may occur in terms of ground water quantity discharges or of the quality of the
ground water discharged. This report provided the estimated quality of the water discharge. However, this report does not
speak to the sewer capacities. The sewer capacity analysis is provided under a separate cover by the civil consultant.
The quality of the proposed ground water discharge is provided in previous Sections. As noted in that section the ground
water sample exceeded the Limits for Storm Sewer Discharge and met the Limits for Sanitary and Combined Sewer
Discharge.
As such additional treatment will be required before the water can be discharge to the Storm Sewer and additional
treatment will not be required before the water can be discharge to the Sanitary and Combined Sewer, in order to avoid
impacts to the City’s sewage works cause by ground water quality.
12.2 Negative Impacts to the Natural Environment
There are no natural waterbodies within the ZOI that will be caused by the proposed construction dewatering or long term
drainage. Any ground water that will be taken from the site will be discharged (if required) into the City’s sewer systems
and not into any natural water body. As such, there will be no impact to the natural environment caused by the water
takings at the site.
12.3 Local Wells and Zone of Influence
The Site is located in a serviced area of The City of Toronto. The Site and surrounding area are provided with municipal
piped water and sewer supply. There is no use of the ground water for water supply in this area of Toronto. As such, it is
expected that there would be no impact to drinking water wells.
No domestic water wells are located within a 250 m radius of the Site. No domestic water wells were located on adjacent
properties to the Site.
12.4 Contamination Sources
The Site and immediately surrounding area currently consists mostly of residential and commercial areas. The
environmental investigation of the property is currently being conducted. The primary Potential Contaminate of Concern
(PCoC) in ground water is Volatile Organic Compounds (VOCs). However, it is noted that the ground water quality at the
property meet the City of Toronto Sanitary Sewer Discharge Limits for the PCoC. As such, the pumping of ground water
at the Site is not anticipated to facilitate the movement of potential contaminants onto the property in exceedance of the
City’s Sewer Limits.
Hydrological Review October 23, 2018 12, 16, 18 and 20 Cordova Avenue, Toronto, Ontario File No. 1-17-0848-46
Terraprobe Page No. 12
12.5 Impacts to Land Stability
The impacts to land stability of the proposed short and long term dewatering at the subject site on adjacent structures are
summarized as follows:
The proposed dewatering at the subject site locally lowers the ground water table within the ZOI by a maximum of 12 ±m,
which implies a maximum effective stress increase of about 120 kPa in the native soils.
Based on the change in effective stress and the compressibility of the soil subjected to that change, the proposed
dewatering activities will induce a maximum 2 mm of additional settlement in the adjacent soils. The maximum induced
settlement occurs directly adjacent to the proposed excavation and decreases in a nonlinear fashion with distance away
from the excavation.
Within the founding soils below the nearest footing (north of the exaction), the settlement induced by the proposed
lowering of the ground water table is calculated to be 1 mm or less. Only the nearest footing (closest to the south property
line of the north-side structure) will be impacted by lowering the ground water table. Foundations supported by caisson
walls will be maintained in an at-rest state, with an induced settlement of 0 mm.
For the structures within the public realm on the east and west sides of the subject site, the dewatering-induced settlement
is calculated to be 1 mm or less (depending on the depth and proximity of the public realm structure).
On this basis, the impact of the proposed temporarily lowered ground water table on the existing adjacent structures is
considered by Terraprobe to be within acceptable limits. Shoring-related monitoring and inspection services are to be
provided as part of the proposed development.
13.0 PROPOSED MITIGATION MEASURES AND MONITORING PLAN
Changes in the ground water table have the potential to cause settlement based on the change in effective stress. Within
the zone of influence, changes in ground water level have the potential to cause settlement based on the change in the
effective stresses that will result from dewatering and draining the soil.
Consideration should be given to implement a monitoring and mitigation program during dewatering activities to confirm
that there are no potential implications to existing structures.
Both the temporary construction dewatering system and the permanent building drainage system must be properly
installed and screened to ensure sediments and fines will not be removed, which is typically a primary cause of
dewatering related settlement.
Counterpoint Engineering Inc.
Project: 12 - 20 Cordova Avenue
Project No: 18056
Location: Toronto, Ontario
Site Area: 0.246 ha
Existing Equivalent Population Calculations
As per Design Criteria for Sewers and Watermains - First Edition November 2009 City of Toronto
Design flow = average daily dry weather flow x peaking factor + infiltration
Persons Per Unit and per Land Use
Single Family Dwelling 3.5 ppu
1BR/1BR+Den 1.4 ppu
2BR/2BR+Den/ 2.1 ppu
3BR/3BR+Den 3.1 ppu
Commercial / Retail 1.1 persons/100m2
Offices 3.3 persons/100m2
# of Floors Area (m2)
Total Units / Area
(m2)
Existing Parkland 0 0 0
TOTAL
UNITS
PERSONS PER
UNIT
TOTAL
POPULATION
Residential 4 4 14
Retail - 0
Office - 0
14
.
Peak flow Design Parameters
Residential Average flow 240 litres/person/day
Commercial Average flow 250 litres/person/day
Infiltration 0.26 litres/second/ha
Harmon Peaking Factor
PF = 1 + (14/(4+(P/1000)1/2
))
Total Population
Harmon
Peak Factor
14 4.40
Average Dry Weather Flow 0.04 l/s
Total Peak Wastewater Flow 0.17 l/s
Infiltration 0.06 l/s
Flow 0.24 l/s
Residential Units
Total Equivalent Population
Counterpoint Engineering Inc.
Project: 12 - 20 Cordova Avenue
Project No: 18056
Location: Toronto
Site Area: 0.246 ha
Proposed Sanitary Flow CalculationsAs per Design Criteria for Sewers and Watermains - First Edition November 2009 City of Toronto
Design flow = average daily dry weather flow x peaking factor + infiltration
Persons Per Unit and per Land Use
1BR/1BR+Den 1.4 ppu
2BR/2BR+Den/ 2.1 ppu
3BR/3BR+Den 3.1 ppu
Commercial / Retail 1.1 persons/100m2
Offices 3.3 persons/100m2
1B / 1B+D 2B / 2B + D 3B / 3B+D Total Units Area (m2)
Level 1 - 27 164 131 32 327 0
TOTAL UNITS / AREA (m2) 164 131 32 327 0
Population
1BR / 1B + D
Population
2BR / 2BR + D
Population
3BR / 3BR + D
TOTAL
POPULATION
Residential 230 276 100 606
Total Equivalent Population 606
Peak flow Design Parameters
Residential Average flow 240 litres/person/day
Commercial Average flow 180,000 litres/ha/day
Infiltration 0.26 litres/second/ha
Harmon Peaking Factor
PF = 1 + (14/(4+(P/1000)1/2
))
Residential Population
Harmon Peak
Factor
606 3.93
Residential Flow 6.62 L/s
Infiltration 0.06 L/s
Groundwater Flows 4.73 L/s *assuming a 75 USGPM pump
Flow 11.41 L/s
Residential Units
Existing Dry Conditions Sanitary Flow
12 - 20 Cordova Avenue, Etobicoke, OntarioComposite population density Population density-Commercial 1.1 p / 100 m
2
per unit Single - 3.5 Population density-Office 3.3 p / 100 m2
p - Equivalent residential population density (based on ppl/ha)
Semi & Townhouse - 2.7 Population density-School 0.0286 p / m2
AREA - Area of the commercial/institutional/industrial site
P = population = sum p A site A = area ha EQUIV RES P - Equivalent residential population (based on ppl/ha)
M = 1+ (14)/(4+(P/103))
0.5Pflow = M q P / 86400 = population flow l/s Date: 12-Nov-18 RES UNITS - Residential number of units
I = 0.26 x A gross l/s Q TOTAL = P flow + I l/s Designed by: RS RES POP P - Residential population
q = 240 l/person/day (For the analysis of existing sewers) Checked by: A SITE - Residential Area
A GROSS - Cumulative Residential + Non-Residential Area
STREET A I Q LENGTH SLOPE D TYPE ROUGH. Q Velocity Capacity
FROM TO AREA EQUIV. POP. M PEAK GROSS TOTAL (m) S % OF COEFF. FULL Full
POP P FLOW
ha P l/s ha l/s l/s (mm) PIPE (L/s) (m/s) (%)
Input: UPSTREAM MHA1 MHA2 17.50 2215 2215 3.60 22.2 17.50
Cordova Avenue(Site) MHA2 MHA3 0.53 24 2239 3.50 21.8 18.03 4.69 26.5 76.8 1.27 450 UNK 0.011 334.8 2.04 8%
Cordova Avenue(School) MHA3 MHA4 2.50 48 2287 3.50 22.2 20.53 5.34 27.6 9.3 2.40 375 UNK 1.011 283.4 2.49 10%
Central Park Roadway MHA4 MHA5 0.00 0 2287 3.50 22.2 20.53 5.34 27.6 9.3 2.04 375 UNK 2.011 261.2 2.29 11%
Input: CORDOVA SOUTH MHA12 MHA5 6.60 4676 6963 3.10 60.0 27.13
Central Park Roadway MHA5 MHA6 0.00 0 6963 3.10 60.0 27.13 7.05 67.0 76.2 2.79 375 UNK 0.011 305.5 2.68 22%
Central Park Roadway(North) MHA6 MHA7 1.30 187 7150 3.10 61.6 28.43 7.39 69.0 75.0 2.62 375 UNK 0.011 296.1 2.60 23%
Input: ISLINGTON AVENUE MHA11 MHA7 3.50 1123 8273 3.00 68.9 31.93
Central Park Roadway MHA7 MHA8 0.00 0 8273 3.00 68.9 31.93 8.30 77.2 60.5 0.36 450 UNK 0.011 178.3 1.09 43%
Central Park Roadway MHA8 MHA9 0.00 0 8273 3.00 68.9 31.93 8.30 77.2 55.1 0.41 450 UNK 0.011 190.2 1.16 41%
Central Park Roadway MHA9 MHA10 0.00 0 8273 3.00 68.9 31.93 8.30 77.2 25.2 0.35 450 UNK 0.011 175.8 1.07 44%
MANHOLE CUMULATIVE
1 of 4
Existing Wet Conditions Sanitary Flow
12 - 20 Cordova Avenue, Etobicoke, OntarioComposite population density Population density-Commercial 1.1 p / 100 m
2
per unit Single - 3.5 Population density-Office 3.3 p / 100 m2
p - Equivalent residential population density (based on ppl/ha)
Semi & Townhouse - 2.7 Population density-School 0.0286 p / m2
AREA - Area of the commercial/institutional/industrial site
P = population = sum p A site A = area ha EQUIV RES P - Equivalent residential population (based on ppl/ha)
M = 1+ (14)/(4+(P/103))
0.5Pflow = M q P / 86400 = population flow l/s Date: 12-Nov-18 RES UNITS - Residential number of units
I = 3.0 x A gross l/s Q TOTAL = P flow + I l/s Designed by: RS RES POP P - Residential population
q = 240 l/person/day (For the analysis of existing sewers) Checked by: A SITE - Residential Area
A GROSS - Cumulative Residential + Non-Residential Area
STREET A I Q LENGTH SLOPE D TYPE ROUGH. Q Velocity Capacity
FROM TO AREA EQUIV. POP. M PEAK GROSS TOTAL (m) S % OF COEFF. FULL Full
POP P FLOW
ha P l/s ha l/s l/s (mm) PIPE (L/s) (m/s) (%)
Input: UPSTREAM MHA1 MHA2 17.50 2215 2215 3.60 22.2 17.50
Cordova Avenue(Site) MHA2 MHA3 0.53 597 2812 3.50 27.3 18.03 54.09 81.4 76.8 1.27 450 UNK 0.011 334.8 2.04 24%
Cordova Avenue(School) MHA3 MHA4 2.50 48 2860 3.50 27.8 20.53 61.59 89.4 9.3 2.40 375 UNK 0.011 283.4 2.49 32%
Central Park Roadway MHA4 MHA5 0.00 0 2860 3.50 27.8 20.53 61.59 89.4 9.3 2.04 375 UNK 1.011 261.2 2.29 34%
Input: CORDOVA SOUTH MHA12 MHA5 6.60 4676 7536 3.10 64.9 27.13
Central Park Roadway MHA5 MHA6 0.00 0 7536 3.10 64.9 27.13 81.39 146.3 76.2 2.79 375 UNK 0.011 305.5 2.68 48%
Central Park Roadway(North) MHA6 MHA7 1.30 187 7723 3.10 66.5 28.43 85.29 151.8 75.0 2.62 375 UNK 0.011 296.1 2.60 51%
Input: ISLINGTON AVENUE MHA11 MHA7 3.50 1123 8846 3.00 73.7 31.93
Central Park Roadway MHA7 MHA8 0.00 0 8846 3.00 73.7 31.93 95.79 169.5 60.5 0.36 450 UNK 0.011 178.3 1.09 95%
Central Park Roadway MHA8 MHA9 0.00 0 8846 3.00 73.7 31.93 95.79 169.5 55.1 0.41 450 UNK 0.011 190.2 1.16 89%
Central Park Roadway MHA9 MHA10 0.00 0 8846 3.00 73.7 31.93 95.79 169.5 25.2 0.35 450 UNK 0.011 175.8 1.07 96%
MANHOLE CUMULATIVE
2 of 4
Proposed Dry Conditions Sanitary Flow
12 - 20 Cordova Avenue, Etobicoke, OntarioComposite population density Population density-Commercial 1.1 p / 100 m
2
per unit Single - 3.5 Population density-Office 3.3 p / 100 m2
p - Equivalent residential population density (based on ppl/ha)
Semi & Townhouse - 2.7 Population density-School 0.0286 p / m2
AREA - Area of the commercial/institutional/industrial site
P = population = sum p A site A = area ha EQUIV RES P - Equivalent residential population (based on ppl/ha)
M = 1+ (14)/(4+(P/103))
0.5Pflow = M q P / 86400 = population flow l/s Date: 12-Nov-18 RES UNITS - Residential number of units
I = 0.26 x A gross l/s Q TOTAL = P flow + I l/s Designed by: RS RES POP P - Residential population
q = 240 l/person/day (For the analysis of existing sewers) Checked by: A SITE - Residential Area
A GROSS - Cumulative Residential + Non-Residential Area
STREET A I Q LENGTH SLOPE D TYPE ROUGH. Q Velocity Capacity
FROM TO AREA EQUIV. POP. M PEAK GROSS TOTAL (m) S % OF COEFF. FULL Full
POP P FLOW
ha P l/s ha l/s l/s (mm) PIPE (L/s) (m/s) (%)
Input: UPSTREAM MHA1 MHA2 17.50 2215 2215 3.60 22.2 17.50
Cordova Avenue(Site) MHA2 MHA3 0.53 606 2821 3.50 27.4 18.03 4.69 32.1 76.8 1.27 450 UNK 0.011 334.8 2.04 10%
Cordova Avenue(School) MHA3 MHA4 2.50 48 2869 3.50 27.9 20.53 5.34 33.2 9.3 2.40 375 UNK 1.011 283.4 2.49 12%
Central Park Roadway MHA4 MHA5 0.00 0 2869 3.50 27.9 20.53 5.34 33.2 9.3 2.04 375 UNK 2.011 261.2 2.29 13%
Input: CORDOVA SOUTH MHA12 MHA5 6.60 4676 7545 3.10 65.0 27.13
Central Park Roadway MHA5 MHA6 0.00 0 7545 3.10 65.0 27.13 7.05 72.0 76.2 2.79 375 UNK 0.011 305.5 2.68 24%
Central Park Roadway(North) MHA6 MHA7 1.30 187 7732 3.10 66.6 28.43 7.39 74.0 75.0 2.62 375 UNK 0.011 296.1 2.60 25%
Input: ISLINGTON AVENUE MHA11 MHA7 3.50 1123 8855 3.00 73.8 31.93
Central Park Roadway MHA7 MHA8 0.00 0 8855 3.00 73.8 31.93 8.30 82.1 60.5 0.36 450 UNK 0.011 178.3 1.09 46%
Central Park Roadway MHA8 MHA9 0.00 0 8855 3.00 73.8 31.93 8.30 82.1 55.1 0.41 450 UNK 0.011 190.2 1.16 43%
Central Park Roadway MHA9 MHA10 0.00 0 8855 3.00 73.8 31.93 8.30 82.1 25.2 0.35 450 UNK 0.011 175.8 1.07 47%
MANHOLE CUMULATIVE
3 of 4
Proposed Wet Conditions Sanitary Flow
12 - 20 Cordova Avenue, Etobicoke, OntarioComposite population density Population density-Commercial 1.1 p / 100 m
2
per unit Single - 3.5 Population density-Office 3.3 p / 100 m2
p - Equivalent residential population density (based on ppl/ha)
Semi & Townhouse - 2.7 Population density-School 0.0286 p / m2
AREA - Area of the commercial/institutional/industrial site
P = population = sum p A site A = area ha EQUIV RES P - Equivalent residential population (based on ppl/ha)
M = 1+ (14)/(4+(P/103))
0.5Pflow = M q P / 86400 = population flow l/s Date: 12-Nov-18 RES UNITS - Residential number of units
I = 3.0 A gross x L/s Q TOTAL = P flow + I l/s Designed by: RS RES POP P - Residential population
q = 240 l/person/day (For the analysis of existing sewers) Checked by: A SITE - Residential Area
A GROSS - Cumulative Residential + Non-Residential Area
STREET A I Q LENGTH SLOPE D TYPE ROUGH. Q Velocity Capacity
FROM TO AREA EQUIV. POP. M PEAK GROSS TOTAL (m) S % OF COEFF. FULL Full
POP P FLOW
ha P l/s ha l/s l/s (mm) PIPE (L/s) (m/s) (%)
Input: UPSTREAM MHA1 MHA2 17.50 2215 2215 3.60 22.2 17.50
Cordova Avenue(Site) MHA2 MHA3 0.53 606 2821 3.50 27.4 18.03 58.82 86.2 76.8 1.27 450 UNK 0.011 334.8 2.04 26%
Cordova Avenue(School) MHA3 MHA4 2.50 48 2869 3.50 27.9 20.53 66.32 94.2 9.3 2.40 375 UNK 0.011 283.4 2.49 33%
Central Park Roadway MHA4 MHA5 0.00 0 2869 3.50 27.9 20.53 66.32 94.2 9.3 2.04 375 UNK 1.011 261.2 2.29 36%
Input: CORDOVA SOUTH MHA12 MHA5 6.60 4676 7545 3.10 65.0 27.13
Central Park Roadway MHA5 MHA6 0.00 0 7545 3.10 65.0 27.13 86.12 151.1 76.2 2.79 375 UNK 0.011 305.5 2.68 49%
Central Park Roadway(North) MHA6 MHA7 1.30 187 7732 3.10 66.6 28.43 90.02 156.6 75.0 2.62 375 UNK 0.011 296.1 2.60 53%
Input: ISLINGTON AVENUE MHA11 MHA7 3.50 1123 8855 3.00 73.8 31.93
Central Park Roadway MHA7 MHA8 0.00 0 8855 3.00 73.8 31.93 100.52 174.3 60.5 0.36 450 UNK 0.011 178.3 1.09 98%
Central Park Roadway MHA8 MHA9 0.00 0 8855 3.00 73.8 31.93 100.52 174.3 55.1 0.41 450 UNK 0.011 190.2 1.16 92%
Central Park Roadway MHA9 MHA10 0.00 0 8855 3.00 73.8 31.93 100.52 174.3 25.2 0.35 450 UNK 0.011 175.8 1.07 99%
MANHOLE CUMULATIVE
4 of 4
S
IT
E
A=
P=
17.5ha
M1-M2
2215
MHA1
MHA2
MHA3
MHA7
MHA8
MHA9
MHA10
MHA12
MHA4
MHA11
A=
P=
6.6ha
M12-M5
4676
A=
P=
2.5ha
M3-M4
48
A=
P=
3.5ha
M11-M7
1123
A=
P=
1.3ha
M6-M7
187
A=
P=
0.53ha
M2-M3
18
MHA6
MHA5
8395 Jane St., Suite 100, Vaughan, ON L4K 5Y2Phone 905.326.1404Fax 905.326.1405
COUNTERPOINT ENGINEERING INC.
4
18056
EXISTING SANITARY DRAINAGE PLAN
LEGEND
A=
P=
0.66ha
M10-M11
25
MIXED USE - COMMERCIAL RESIDENTIAL
12 - 20 CORDOVA AVENUE
S
IT
E
A=
P=
17.5ha
M1-M2
2215
MHA1
MHA2
MHA3
MHA7
MHA8
MHA9
MHA10
MHA12
MHA4
MHA11
A=
P=
6.6ha
M12-M5
4676
A=
P=
2.5ha
M3-M4
48
A=
P=
3.5ha
M11-M7
1123
A=
P=
1.3ha
M6-M7
187
A=
P=
0.53ha
M2-M3
MHA6
MHA5
606
5
18056
8395 Jane St., Suite 100, Vaughan, ON L4K 5Y2Phone 905.326.1404Fax 905.326.1405
COUNTERPOINT ENGINEERING INC.
PROPOSED SANITARY DRAINAGE PLAN
MIXED USE - COMMERCIAL RESIDENTIAL
12 - 20 CORDOVA AVENUE
LEGEND
A=
P=
0.66ha
M10-M11
25
Project No.: 18056
November 2018
Minto Communities
12-20 Cordova Avenue
Appendix D
Counterpoint EngineeringAllowable Release Rate
12 - 20 Cordova
18056
Rational Method - 2 Year Predevelopment
Event: 2 years
ABC's: A 21.8
C 0.78
Time of Concentration: t 10 min
Runoff Coefficient: C 0.5
Site Area A 0.246 ha
Intensity i 88.19 mm/hr
i=A/(T)c
Flow Q 0.030 m3/s
Q=CiA/360 30.1 l/s
Project Name:
Project Number:
Counterpoint EngineeringPredevelopment Flows - To Cordova Avenue
12 - 20 Cordova
18056
Rational Method - 2 Year Predevelopment Rational Method - 5 Year Predevelopment Rational Method - 10 Year Predevelopment
Event: 2 years Event: 5 years Event: 10 years
ABC's: A 21.8 ABC's: A 32 ABC's: A 38.7
C 0.78 C 0.79 C 0.8
Time of Concentration: t 10 min Time of Concentration: t 10 min Time of Concentration: t 10 min
Runoff Coefficient: C 0.65 Runoff Coefficient: C 0.65 Runoff Coefficient: C 0.65
Site Area A 0.246 ha Site Area A 0.246 ha Site Area A 0.246 ha
Intensity i 88.19 mm/hr Intensity i 131.79 mm/hr Intensity i 162.27 mm/hr
i=A/(T)c
i=A/(T)c
i=A/(T)c
Flow Q 0.04 m3/s Flow Q 0.06 m
3/s Flow Q 0.07 m
3/s
Q=CiA/360 39 l/s Q=CiA/360 59 l/s Q=CiA/360 72 l/s
Rational Method - 25 Year Predevelopment Rational Method - 50 Year Predevelopment Rational Method - 100 Year Predevelopment
Event: 25 years Event: 50 years Event: 100 years
ABC's: A 45.2 ABC's: A 53.5 ABC's: A 59.7
C 0.8 C 0.8 C 0.8
Time of Concentration: t 10 min Time of Concentration: t 10 min Time of Concentration: t 10 min
Runoff Coefficient: C 0.65 Runoff Coefficient: C 0.65 Runoff Coefficient: C 0.65
Site Area A 0.246 ha Site Area A 0.246 ha Site Area A 0.246 ha
Intensity i 189.52 mm/hr Intensity i 224.32 mm/hr Intensity i 250.32 mm/hr
i=A/(T)c
i=A/(T)c
i=A/(T)c
Flow Q 0.08 m3/s Flow Q 0.10 m
3/s Flow Q 0.11 m
3/s
Q=CiA/360 84 l/s Q=CiA/360 100 l/s Q=CiA/360 111 l/s
Project Name:
Project Number:
Counterpoint Engineering
Rational Method - Uncontrolled Area to Cordova Avenue (Post Development)
Project Name: 12 - 20 Cordova
Project No: 18056
Event: 100 years
ABC's: A 59.7
C 0.8
Time of Concentration: t 10 min
Runoff Coefficient: C 0.81 (Planters along Cordova)
Site Area A 0.030 ha
Intensity i 250.32 mm/hr
i=A/(T)c
Flow Q 0.017 m3/s
Q=CiA/360 16.8 l/s
counterpoint engineering
12 - 20 Cordova
18056
Location: a 59.7
Event b 0
c 0.8
Area ID Area (ha)
Runoff
Coefficient
tc
(min)
Storage
Available
(m3)
Storage
Required
(m3)
Release
Rate (L/s) Description
Orifice Size
(mm)
Uncontrolled 0.030 0.81 10 TBD N/A 16.8 Uncontrolled to Cordova -
SITE 0.246 0.69 10 TBD 65 13.3 Orifice Plate At SPA
0.276 TBD 65 30.1
1 On-site storage will be provided via an ungerground storage tank located within the building
2
AREA ID SITE
Area [ha] RC RC * Area
0.066 0.35 0.0229
0.025 0.25 0.0063 Planters along south and west perimeter
0.156 0.90 0.1401
0.246 Total 0.1693
Divided by Total Area = 0.69
AREA ID Uncontrolled
Area [ha] RC RC * Area
0.005 0.35 0.0018
0.025 0.90 0.0225
0.030 Total 0.0243
Divided by Total Area = 0.81
Refer to Appendix D for modified rational calculations .
Project Name:
Project Number:
Rainfall Data
100 Year
Toronto
Building/Impervious Area
Building/Impervious Area
Green Roof
Composite RC Value
Composite RC Value
Impervious Area
Pervious Area
Counterpoint Engineering
Modified Rational Area: SITE
Project Name: 12 - 20 Cordova
Project Number: 18056
Location: Toronto a 59.700
Event 100 Year b 0.000
c 0.800
Area 0.246 ha
Runoff Coefficient 0.69
AC 0.17
Tc 10
Time Increment 10
Release Rate 13.3 l/s
Storage Required 65 m3
Time Rainfall Intensity
Storm
Runoff
Runoff
Volume
Released
Volume
Storage
Volume
(min) (mm/hr) (m3/s) (m
3) (m
3) (m
3)
10 250 0.12 71 8 63
20 144 0.07 81 16 65 ********
30 104 0.05 88 24 64
40 83 0.04 93 32 61
50 69 0.03 98 40 58
60 60 0.03 101 48 53
70 53 0.02 104 56 48
80 47 0.02 107 64 43
90 43 0.02 110 72 38
100 40 0.02 112 80 32
110 37 0.02 114 88 26
120 34 0.02 116 96 20
130 32 0.02 118 104 14
140 30 0.01 120 112 8
150 29 0.01 122 120 2
160 27 0.01 123 128 -5
170 26 0.01 125 136 -11
180 25 0.01 126 144 -18
190 24 0.01 127 152 -25
200 23 0.01 129 160 -31
210 22 0.01 130 168 -38
220 21 0.01 131 176 -45
230 20 0.01 132 184 -52
Rainfall Data
Site Data
Counterpoint EngineeringWater Balance
12-20 Cordova Avenue
City of Toronto's Green Standard Tier 1 Section QW 2.2
1 mm
5 mm
1 mm
Area Units
0.134 ha
0.082 ha
0.030 ha
0.246 ha
Initial Abstraction= Percent Impervious (Roof) *R + Percent Impervious (Asphalt)* I + Percent Previous Green Roof * P
Initial Abstraction= 0.54 x 1mm + 0.33 x 0.6mm + 0.12 x 5mm
Initial Abstraction (credit)= 1.49 mm
Required Development Retention = (Excess Rainfall- Initial Abstraction) * (Total Development Area)
Required Development Retention = (5mm - 1.5 mm) x ( 0.246 )ha
Required Development Retention (debit)= 8.7 m3
12%
100%
Non-Green Roof Building Area
Pervious / Green Roof Area
Total Area
% Redevelopment
Area
54%
33%
Initial Abstraction Asphalt, I
Initial Abstraction Pervious, P
Initial Abstraction Roof, R
Toronto's small design rainfall event has 5mm excess rainfall
Type of Area
Asphalt Impervious Area