functional servicing and stormwater management …

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

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


Project No.: 18056

November 2018

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


Project No.: 18056

November 2018

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


Project No.: 18056

November 2018

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


Project No.: 18056

November 2018

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


Project No.: 18056

November 2018

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


Project No.: 18056

November 2018

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


Project No.: 18056

November 2018

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


Project No.: 18056

November 2018

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


Project No.: 18056

November 2018

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


Project No.: 18056

November 2018

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


Project No.: 18056

November 2018

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


A=C=

0.15SITE

0.55

12, 16, 18 & 20 CORDOVA AVENUE

PROPOSED MIXED USED COMMERCIAL &

RESIDENTIAL DEVELOPMENT

Minto Cordova LP


Project No.: 18056

November 2018

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


Project No.: 18056

November 2018

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

ROOF

PU

BL

IC

L

AN

E

PRIVA

TE TE

RRAC

ES AT

THE 2

7TH F

LOOR

PRIVATE TERRACE AT THE 13TH FLOOR

PRIVA

TE TE

RRAC

E AT T

HE 13

TH FL

OOR

PRIVA

TE TE

RRAC

ES AT

THE 1

3TH F

LOOR

OPEN

TO M

ECH

AREA

BELO

W

LOWE

R ROO

F

PRIVA

TE TE

RRAC

EAT

THE 2

ND FL

OOR

13T

H F

LO

OR

G

RE

EN

R

OO

F

0.00m

2

27T

H F

LO

OR

G

RE

EN

R

OO

F

0.00m

2

2N

D F

LO

OR

G

RE

EN

RO

OF

0.00m

2

LO

WE

R G

RE

EN

R

OO

F

0.00m

2

GR

EE

N R

OO

F

0.00m

2

MPH

ROOF

13T

H F

LO

OR

G

RE

EN

RO

OF

0.00m

2

13T

H F

LO

OR

G

RE

EN

R

OO

F

0.00m

2

GARB

AGE

CHUT

EFL

UE

PRIVA

TE TE

RRAC

E AT T

HE 5T

H FLO

OR

A=C=

0.069G ROOF

0.45

A=C=

0.061NG ROOF

0.90

A=C=

0.116100

0.90

N.T.S



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


Project No.: 18056

November 2018

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


Project No.: 18056

November 2018

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


Project No.: 18056

November 2018

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


Project No.: 18056

November 2018

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


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


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


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


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


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


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


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



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 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)


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



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



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



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



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



BH3 SS6 1.91 x 10-2 Gravelly sand 3.65 x 10-6



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:



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.



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


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


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



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



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.



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.


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


3BR/3BR+Den 3.1 ppu



# 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


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


3BR/3BR+Den 3.1 ppu



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(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




MANHOLE CUMULATIVE

1 of 4

Existing Wet Conditions Sanitary Flow


2






M = 1+ (14)/(4+(P/103))







POP P FLOW













MANHOLE CUMULATIVE

2 of 4

Proposed Dry Conditions Sanitary Flow


2






M = 1+ (14)/(4+(P/103))







POP P FLOW













MANHOLE CUMULATIVE

3 of 4

Proposed Wet Conditions Sanitary Flow


2






M = 1+ (14)/(4+(P/103))


I = 3.0 A gross x L/s Q TOTAL = P flow + I l/s Designed by: RS RES POP P - Residential population





POP P FLOW













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



4

18056

EXISTING SANITARY DRAINAGE PLAN

LEGEND

A=

P=

0.66ha

M10-M11

25



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



PROPOSED SANITARY DRAINAGE PLAN



LEGEND

A=

P=

0.66ha

M10-M11

25

Project No.: 18056

November 2018

Minto Communities


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


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

functional servicing and stormwater management …

Documents