edgehill properties limited c/o ... - centre wellington · stormwater management block, as shown on...

Guelph | Owen Sound | Listowel | Kitchener | London | Hamilton | GTA

650 Woodlawn Rd. W., Block C, Unit 2, Guelph ON N1K 1B8 P: 519.824.8150 www.GMBluePlan.ca

Prepared By:

Edgehill Properties Limited c/o Wrighthaven Homes Ltd.

FUNCTIONAL SERVICING AND STORMWATER MANAGEMENT REPORT

Granwood Gate Subdivision, Phase III Township of Centre Wellington (Elora)

GMBP File No. 114152-1 July 2017

FUNCTIONAL SERVICING AND SWM REPORT

EDGEHILL PROPERTIES LIMITED

C/O WRIGHTHAVEN HOMES LTD.

GRANWOOD GATE SUBDIVISION, PHASE III

GMBP FILE NO. 114152-1

JULY 2017

I

TABLE OF CONTENTS

1. INTRODUCTION .......................................................................................................................... 1

2. SITE INFORMATION................................................................................................................... 1

3. PROPOSED DEVELOPMENT................................................................................................... 2

3.1 Sanitary System ............................................................................................................... 2

3.2 Storm System ................................................................................................................... 2

3.3 Water System ................................................................................................................... 3

4. STORMWATER MANAGEMENT .............................................................................................. 4

4.1 Design Criteria .................................................................................................................. 4

4.2 Pre-Development Conditions ......................................................................................... 4 4.3 Post-Development Conditions ........................................................................................ 5 4.3 Routing ............................................................................................................................... 6

5. WATER QUALITY ........................................................................................................................ 7

6. ROADWAYS AND GRADING .................................................................................................... 7

7. CONCLUSIONS ........................................................................................................................... 8

LIST OF FIGURES Figure No. 1 Site Location Map Figure No. 2 Site Layout Figure No. 3 Typical Road Cross Section Figure No. 4 Granwood Subdivision Pond Outlet Figure No. 5 Pre-Development Drainage Area Plan Figure No. 6 Post-Development Drainage Area Plan

LIST OF APPENDICES Appendix ‘A’ Preliminary Geotechnical Investigation, prepared by Trow Consulting Engineers Ltd.,

revised August 27, 1999 Appendix ‘B’ Township of Centre Wellington Preliminary Outlet Storm Sewer Design Appendix ‘C’ MIDUSS IDF Curve Fit Modeling Appendix ‘D’ Pre-Development MIDUSS Computer Model Output for the 2-, 5- and 100-Year Design

Storms Appendix ‘E’ Post-Development MIDUSS Computer Model Output for the 2-, 5- and 100-Year Design

Storms and Stage-Storage Discharge Calculation Tables Appendix ‘F’ Wetland Facility Sizing Details

LIST OF DRAWINGS Drawing No. 1 Preliminary General Servicing Drawing No. 2 Proposed Grading Drawing No. 3 Stormwater Management Facility Sections





GMBP FILE NO.114152-1

JULY 2017

1 OF 5

1. INTRODUCTION

In support of the Draft Plan of Subdivision Application, this Functional Servicing and Stormwater Management Report documents the proposed site servicing and stormwater management design for the proposed Phase III of the Granwood Subdivision located in the Village of Elora within the Township of Centre Wellington (Town), as shown on Figure No. 1. The Granwood Gate Subdivision was originally designed by K.J. Behm & Associates Inc. and approved in approximately 2004. The subdivision was proposed to be constructed in three (3) phases. Phase I and II have since been fully serviced and residents have been living within Phase I and II for several years. Phase III was rough graded, but was never serviced. This current Draft Plan of Subdivision Application and Functional Servicing and Stormwater Management Report are being submitted due to the lapse of the previous Draft Plan and conditions.

The existing and proposed site details are shown on the Preliminary Site Grading and Servicing Plans (attached).

2. SITE INFORMATION

Phase III covers an area of approximately 8.76 hectares and consists of a total of 54 single family residential lots, 12 semi-detached lots, 20 on-street townhouses, 66 stacked townhouses, a walkway block and a stormwater management block, as shown on Figure No. 2. The site is currently vacant with grass and shrubbery cover. The subject property is irregular in shape with a frontage of approximately 335 metres along Waterloo Street. For the purposes of this report, the Waterloo Street right-of-way adjacent to the site is assumed to run north-south and is assumed to be west of the site. The site is bound to the north by residential lots located along the south side of McNab Street East, Clarke Street and York Street (Granwood Gate Subdivision Phase I and II) to the east, Waterloo Street to the west, and bound to the south by the Trestle Bridge Trail followed by the Jefferson Elora Corporation property. The Wellington County Soils Map (Ontario Soil Survey Report No. 35), prepared by the Department of Agriculture, describe soils at the site as smooth, gently sloping, Grey-Brown Podzolic, stone free loam till, with good drainage characteristics.

FUNCTIONAL SERVICING AND STORMWATER MANAGEMENT REPORT

WRIGHTHAVEN HOMES LIMITED


TOWNSHIP OF CENTRE WELLINGTON (ELORA)

JULY 2017

GMBP FILE NO. 114152-1

T

R

E

S

T

L

E

B

R

I

D

G

E

T

R

A

I

L

W

A

T

E

R

L

O

O

S

T

.

Y

O

R

K

S

T

.

W

N

I

C

H

O

L

S

T

.

W

E

L

L

I

N

G

T

O

N

S

T

.

M

c

N

A

B

S

T

.

P

A

R

K

R

D

.

V

I

C

T

O

R

I

A

S

T

.

W

E

L

L

I

N

G

T

O

N

R

D

.

7

M

c

N

A

B

S

T

.

W

A

T

E

R

S

T

.

H

I

G

H

S

T

.

C

A

R

L

T

O

N

P

L

. C

L

Y

D

E

S

T

.

E

L

G

I

N

S

T

.

C

L

A

R

K

S

T

.

W

A

L

K

I

N

G

B

R

I

D

G

E

T

R

A

I

L

B

R

I

D

G

E

S

T

.

H

A

L

L

S

D

R

.

F

I

S

H

E

R

S

T

.

C

L

A

R

K

E

S

T

.

M

U

R

R

A

Y

D

R

.

R

O

N

A

L

D

S

T

.

D

I

C

K

S

O

N

C

R

T

.

C

U

T

T

I

N

G

D

R

.

W

A

T

E

R

S

T

.

E

A

S

T

M

I

L

L

S

T

.

C

H

A

L

M

E

R

S

S

T

.

M

E

L

V

I

L

L

E

S

T

.

P

R

I

N

C

E

S

S

S

T

.

G

E

D

D

E

S

S

T

.

G

R

A

N

D

R

I

V

E

R

B

R

I

D

G

E

S

T

.

Y

O

R

K

S

T

.

E

Y

O

R

K

S

T

.

E

M

c

N

A

B

S

T

.

E

A

S

T

M

I

L

L

S

T

.

M

E

T

C

A

L

F

S

T

.

M

E

T

C

A

L

F

S

T

.

SUBJECT

PROPERTY

FIL

E:W

:\G

ue

lp

h\1

14

-2

01

4\1

14

15

2-1

G

ra

nw

oo

d S

WM

R

evie

w\5

W

ork In

P

ro

gre

ss\D

ra

ftin

g\1

14

15

2 F

IG

UR

ES

.d

wg

L

AY

OU

T:S

IT

E M

AP

LA

ST

S

AV

ED

B

Y:B

vla

sm

an, 7

/2

0/2

01

7 2

:1

5:0

9 P

M P

LO

TT

ED

B

Y:B

arry V

la

sm

an

- G

M B

lu

eP

la

n 7

/2

0/2

01

7 2

:2

5:5

2 P

M

Not To Scale

N

BluePlan

ENGINEERING

114152-1

JULY 2017

Scale: N.T.S. | NAD 1983 UTM Zone 17N

GRANWOOD GATE

SUBDIVISION, PHASE 3

TOWNSHIP OF CENTRE

WELLINGTON (ELORA)

SITE

LOCATION MAP

Figure No. 1

FIL

E:W

:\G

ue

lp

h\1

14

-2

01

4\1

14

15

2-1

G

ra

nw

oo

d S

WM

R

evie

w\5

W

ork In

P

ro

gre

ss\D

ra

ftin

g\1

14

15

2 F

IG

UR

ES

.d

wg

L

AY

OU

T:S

IT

E L

AY

OU

T

LA

ST

S

AV

ED

B

Y:B

vla

sm

an

, 7

/2

0/2

01

7 2

:1

5:0

9 P

M P

LO

TT

ED

B

Y:B

arry V

la

sm

an

- G

M B

lu

eP

la

n 7

/2

0/2

01

7 2

:2

5:5

3 P

M

030

1:2000

804020

(m)

BluePlan

ENGINEERING

114152-1

JULY 2017

Scale: 1:2000 | NAD 1983 UTM Zone 17N

SITE LAYOUT

GRANWOOD GATE


TOWNSHIP OF CENTRE

WELLINGTON (ELORA)

Figure No. 2

LEGEND

N

PROPOSED LOTLINES

EXISTING LOT LINES

SUBDIVISION BOUNDARY

MUNICIPAL RIGHT OF WAY






JULY 2017

2 OF 8

A Preliminary Geotechnical Investigation was completed by Trow Consulting Engineers Ltd., revised August 27, 1999 for the site and is included as Appendix ‘A’. A total of four (4) test pits were completed on-site which found surficial topsoil which was underlain by fill which was underlain by sandy silt till. The Geotechnical Investigation estimates the groundwater on-site to be 1.8m to 4.1m below grade. The hydraulic conductivity of the underlying soils is estimated at 1x10

-6cm/sec.

Under existing conditions the subject property generally slopes from the east to the west.

3. PROPOSED DEVELOPMENT

The proposed development includes 54 single family residential lots, 12 semi-detached lots, 20 on-street townhouses, 66 stacked townhouses, walkway blocks, a stormwater management block and roadways throughout. A typical on-site roadway section is shown on Figure No. 3.

3.1 Sanitary System

The sanitary sewer system throughout the entire subdivision was originally designed by K.J. Behm & Associates Inc. in approximately 2004. Phase I and II have since been fully serviced and residents have been living within Phase I and II for several years. During the detailed design stage for Phase III, the sanitary sewer design will be peer reviewed in more detail however at this time; it is anticipated that no capacity issues will exist with the current sanitary sewer system or downstream outlet sewers. A portion of the Phase III sanitary sewer was constructed during the development of Phase II along the proposed York street right-of-way in order to service the westerly portion of Phase II. The existing 200mm diameter sanitary sewer continues north along Waterloo Street to Nichol Street and then turns west on Nichol Street. Sanitary service connections to the proposed lots in Phase III were also constructed; however the lot fabric of the development has been revised since the time of construction. The existing service connections will therefore be relocated and/or abandoned as necessary to service the proposed Phase III lots and the existing sanitary sewer will be maintained. As part of Phase III, the sanitary sewer will be extended along Waterloo Street from York Street to the south for approximately 170 metres. This extension will serve as an outlet for the sanitary flows from Halls Drive within Phase III. Individual lateral service connections will be provided for each lot as per current municipal and provincial standards.

3.2 Storm System

As per current practice and guidelines, the stormwater management approach for this development is a “treatment train” designed to remove sediment prior to discharge to the existing municipal storm sewer system. The “treatment train” will include lot level and end-of-pipe management practices. Lot level controls will consist of directing roof leaders to grassed surfaces to promote infiltration. End-of-pipe controls will be provided by a wetland type stormwater management (SWM) facility located along the west property limit of the Phase III development, adjacent to the Waterloo Street right-of-way. Oil/grit separators will also be utilized as part of the treatment train approach to stormwater quality control. These units will be placed within the storm sewer network prior to discharging to the stormwater management pond. The specific design of these oil/grit separators will be considered at the time of detailed design.

20.0m R.O.W

8.00m

E/P TO E/P

1.73m4.27m

1.80m 1.50m

SWLK

2.00% 2.00%

4.00m 4.00m2.20m 2.20m 1.50m

PR

OP

ER

TY

LIN

E

PR

OP

ER

TY

LIN

E

3.65m

ST

RE

ET

LIG

HT

2.40m

1.00m

2.0m

M

IN

0.75m

2.50m

10.00m

0.30m

0.60m

0.75m

CU

RB

S

TO

P

GA

S

ST

OR

M S

EW

ER

SA

NIT

AR

Y S

EW

ER

WA

TE

RM

AIN

GA

TE

V

ALV

E &

B

OX

CA

TC

HB

AS

IN

SU

BD

RA

IN

2.00m

min.

6% SLOPE max.

2% SLOPE min.

BLVD.

1.80m

N.T.S.

℄

1.2.m MIN.

COVER ON

C.B. LEADS

CA

TC

HB

AS

IN

MA

IN

TE

NA

NC

E

HO

LE

HY

DR

AN

T

TYPICAL CROSS SECTION FOR 8.0m

ROAD ON 20.0m R.O.W.

NOTES:

1.) LOCATE HYDRO TRANSFORMER BETWEEN

PROPERTY LINE AND SIDEWALK.

2.) FRONT OF TRANSFORMER TO BE PLACED

150mm FROM BACK OF SIDEWALK.

3.) GAS TO BE PLACED 300mm OFF THE

PROPERTY LINE AT THE TRANSFORMER

LOCATIONS.

HYDRO

BELL & CATV

GA

S

0.50m

FIL

E:W

:\G

ue

lp

h\1

14

-2

01

4\1

14

15

2-1

G

ra

nw

oo

d S

WM

R

evie

w\5

W

ork In

P

ro

gre

ss\D

ra

ftin

g\1

14

15

2 F

IG

UR

ES

.d

wg

L

AY

OU

T:T

YP

. X

-S

EC

LA

ST

S

AV

ED

B

Y:B

vla

sm

an, 7

/2

0/2

01

7 2

:1

5:0

9 P

M P

LO

TT

ED

B

Y:B

arry V

la

sm

an

- G

M B

lu

eP

la

n 7

/2

0/2

01

7 2

:2

5:5

4 P

M

Not To Scale

BluePlan

ENGINEERING

114152-1

JULY 2017

Scale: N.T.S. | NAD 1983 UTM Zone 17N

TYPICAL ROAD

CROSS SECTION

GRANWOOD GATE


TOWNSHIP OF CENTRE

WELLINGTON (ELORA)

Figure No. 3






JULY 2017

3 OF 8

Minor storm runoff from the development will discharge to the SWM facility via the proposed municipal storm sewer system. Major storm runoff exceeding the capacity of the storm sewer system will be conveyed overland via the municipal right-of-way to the SWM facility. There is currently no outlet for the minor storm runoff from Phase III. As part of the Phase III development, a storm sewer outlet is proposed from the outlet pipe of the SWM facility, along Waterloo Street, York Street West, and High Street north to McNab Street, for a distance of approximately 550 metres, where a connection is proposed to the existing 975mm diameter storm sewer that ultimately discharges to the Grand River. The existing 975mm storm sewer outlet to the Grand River was installed by the municipality in anticipation of the proposed Phase III development. The location of the proposed storm sewer is shown in Figure No. 4. Preliminary design of the proposed storm sewer outlet was prepared by the Township of Centre Wellington, and is provided in Appendix ‘B’. The design of the proposed storm sewer outlet will be finalized the time of detailed design. A portion of the Phase III development is proposed to outlet eastward to the existing Phase I & II SWM Pond. The Phase I & II pond was designed to accommodate this portion of the Phase III development. A portion of the Phase III development will drain uncontrolled off-site to the existing Trestle Bridge Trail ditch south of the site. The Phase III SWM facility will be designed with a sediment forebay to provide energy dissipation and promote sediment settlement. The facility will also be designed with an outlet structure to attenuate flows to the proposed storm sewer outlet. Further details regarding the SWM facility are provided in Section 4.0 below.

3.3 Water System A 200mm diameter municipal watermain currently exists along Waterloo Street from approximately South Queen Street to Nichol Street and within the York Street East right-of-way through Phase III. A watermain also currently exists along Fisher Street and Halls Drive within the Phase II portion of the subdivision and is currently stubbed at the boundary of Phase III. A portion of the Phase III watermain was constructed during the development of Phase II along the proposed York street right-of-way. The existing 200mm diameter watermain continues north along Waterloo Street to Nichol Street and then turns west on Nichol Street. As part of the Phase III development, the existing watermain on Waterloo Street will be extended southerly for approximately 50 metres and will be stubbed for a future development connection. A hydrant will be installed at the end of this stub to provide flushing and maintenance capabilities. The existing watermain on Halls Drive will be extended from the existing stub and connect to the proposed watermain extension on Waterloo Street. A watermain is also proposed on Carter Place which will tee off of the existing watermain located within the York Street East right-of-way within Phase III and be installed to the end of the cul-de-sac, terminating at a hydrant to provide flushing and maintenance capabilities. Individual lateral service connections will be provided for each lot as per current municipal and provincial standards.

T

R

E

S

T

L

E

B

R

I

D

G

E

T

R

A

I

L

SUBJECT

PROPERTY

W

A

T

E

R

L

O

O

S

T

.

Y

O

R

K

S

T

.

W

N

I

C

H

O

L

S

T

.

W

E

L

L

I

N

G

T

O

N

S

T

.

M

c

N

A

B

S

T

.

P

A

R

K

R

D

.

V

I

C

T

O

R

I

A

S

T

.

W

E

L

L

I

N

G

T

O

N

R

D

.

7

M

c

N

A

B

S

T

.

W

A

T

E

R

S

T

.

H

I

G

H

S

T

.

C

A

R

L

T

O

N

P

L

.

C

L

Y

D

E

S

T

.

E

L

G

I

N

S

T

.

F

I

S

H

E

R

S

T

.

G

R

A

N

D

R

I

V

E

R

Y

O

R

K

S

T

.

E

E

A

S

T

M

I

L

L

S

T

.

M

E

T

C

A

L

F

S

T

.

SUBJECT

PROPERTY

FIL

E:W

:\G

ue

lp

h\1

14

-2

01

4\1

14

15

2-1

G

ra

nw

oo

d S

WM

R

evie

w\5

W

ork In

P

ro

gre

ss\D

ra

ftin

g\1

14

15

2 F

IG

UR

ES

.d

wg

L

AY

OU

T:O

UT

LE

T F

IG

LA

ST

S

AV

ED

B

Y:B

vla

sm

an, 7

/2

0/2

01

7 2

:1

5:0

9 P

M P

LO

TT

ED

B

Y:B

arry V

la

sm

an

- G

M B

lu

eP

la

n 7

/2

0/2

01

7 2

:2

5:5

4 P

M

030

1:2000

804020

(m)

LEGEND

N

BluePlan

ENGINEERING

114152-1

JULY 2017


THIS DATA IS FOR ILLUSTRATIVE PURPOSES ONLY. INFORMATION CONTAINED HEREON IS NOT A SUBSTITUTE FOR PROFESSIONAL REVIEW OR A SITE SURVEY AND IS

SUBJECT TO CHANGE WITHOUT NOTICE. WELLINGTON COUNTY, AND GM BLUEPLAN TAKE NO RESPONSIBILITY FOR, NOR GUARANTEES, THE ACCURACY OF THE

INFORMATION CONTAINED ON THIS MAP. ANY INTERPRETATIONS OR CONCLUSIONS DRAWN FROM THIS MAP ARE THE SOLE RESPONSIBILITY OF THE USER

EXISTING 975Ø

STORM SEWER

PROPOSED STORM

SEWER

GRANWOOD

SUBDIVISION

POND OUTLET

PROPOSED STM

SEWER

Figure No. 4

GRANWOOD GATE


TOWNSHIP OF CENTRE

WELLINGTON (ELORA)






JULY 2017

4 OF 8

4. STORMWATER MANAGEMENT 4.1 Design Criteria The stormwater management criteria used for the analysis of the site is as follows:

1. The 100-year allowable outlet rate to the proposed storm sewer outlet in the Waterloo Street

right-of-way shall be the lesser of the 100-year pre-development peak flow rate and the design capacity of the outlet storm sewer. Preliminary design of the outlet storm sewer provided by the Township of Centre Wellington indicates that the design capacity of the outlet sewer is approximately 0.840m

3/s. A copy of the Township’s preliminary design is provided in Appendix

‘B’. 2. The post-development peak runoff rates to the proposed storm sewer outlet shall be less than the

pre-development peak runoff rates to the Waterloo Street right-of-way. 3. The minimum acceptable water quality level of discharge from the site is 80% TSS removal.

The Chicago Storm rainfall distributions were used to generate rainfall for the 2-, 5-, and 100-year design storms. Rainfall data was obtained from the Environment Canada Short Duration Rainfall IDF Data for the Fergus Shand Dam station. This data was converted to Chicago Storm parameters using the IDF Curve Fit tool in the MIDUSS modeling software. The Chicago Storm parameters are provided in Table No. 1 below. The MIDUSS Curve Fit modeling is provided in Appendix ‘C’.

Table No. 1: Chicago Storm Parameters Coefficient 2-Year 5-Year 100-Year A 712.297 1510.733 4693.261 B 6.067 11.966 21.472 C 0.796 0.860 0.946 R 0.400 0.400 0.400 Duration (min) 180 180 180 Total Depth (mm) 33.352 49.187 93.070

The SCS Curve Number infiltration method was used in the MIDUSS model. The parameters summarized in the following Table No. 2 were used according to the MTO Drainage Management Manual for a Group ‘BC’ Soil Classification (Design Chart 1.09).

Table No. 2: MIDUSS SCS Curve Number Parameters Group B Group BC Group C Impervious Areas 98 98 98 Long Grass Areas (Meadow) 58 65 71 Lawns (Farmstead) 74 78 82

4.2 Pre-Development Conditions

For pre-development analysis purposes, the site and the external drainage area west of the right-of-way, were modelled as four (4) drainage catchments. The pre-development drainage catchments are shown on Figure No. 5 and described below. The pre-development MIDUSS computer modeling is attached in Appendix ‘D’.

FIS

HE

R S

TR

EE

T

McNAB STREET

NICHOL STREET

YORK STREET

SOUTH QUEEN STREET

(CLOSED)

H

A

L

L

S

D

R

IV

E

W

A

T

E

R

L

O

O

S

T

R

E

E

T

C

L

A

R

K

E

S

T

R

E

E

T

396.0

0

396.0

0

3

9

7

.

0

0

397.0

0

397.00

3

9

8

.

0

0

398.0

0

3

9

8

.

0

0

3

9

8

.

0

0

3

9

8

.

0

0

399.00

399.0

0

3

9

6

.5

0

396.5

0

3

9

7

.

5

0

3

9

7

.

5

0

3

9

7

.

5

0

3

9

7

.5

0

3

9

7

.

5

0

3

9

8

.

5

0

396.0

0

396.00

397.00

3

9

7

.

0

0

3

9

8

.0

0

3

9

9

.

0

0

3

9

9

.

0

0

399.0

0

3

9

9

.

0

0

3

9

9

.

0

0

4

0

0

.

0

0

4

0

0

.0

0

400.00

396.5

0

396.5

0

3

9

7

.5

0

3

9

8

.5

0

3

9

9

.5

0

3

9

9

.

5

0

3

9

9

.

5

0

3

9

9

.

5

0

3

9

9

.

5

0

400.50

396.0

0

396.00

396.00

3

9

6

.

0

0

3

9

6

.

0

0

396.00

3

9

5

.

5

0

3

9

5

.5

0

3

9

6

.5

0

FIL

E:W

:\G

ue

lp

h\1

14

-2

01

4\1

14

15

2-1

G

ra

nw

oo

d S

WM

R

evie

w\5

W

ork In

P

ro

gre

ss\D

ra

ftin

g\1

14

15

2-G

RA

DIN

G.d

wg

L

AY

OU

T:S

TM

F

IG

P

RE

D

EV

L

LA

ST

S

AV

ED

B

Y:B

Vla

sm

an, 7

/1

3/2

01

7 9

:4

3:1

3 A

M P

LO

TT

ED

B

Y:B

arry V

la

sm

an

- G

M B

lu

eP

la

n 7

/2

0/2

01

7 2

:2

5:5

7 P

M

LEGEND

N

BluePlan

ENGINEERING

114152-1

APRIL 2017


CATCHMENT BOUNDARY

AREA IN HECTARES

CATCHMENT NUMBER

10.13ha.

102

90%

% IMPERVIOUS


EXISTING CONTOURS

EXISTING MAJOR

OVERLAND FLOW

030

1:2000

804020

(m)

PRE-DEVELOPMENT

DRAINAGE AREA PLAN

Figure No. 5

GRANWOOD GATE


TOWNSHIP OF CENTRE

WELLINGTON (ELORA)

STORMWATER

MANAGEMENT






JULY 2017

5 OF 8

Catchment 100 (10.25 hectares) represents the existing on-site drainage area which currently drains overland to Waterloo Street. Catchment 100 is comprised of the vacant portion of the site and ground cover consists primarily of grass and shrubbery. Catchment 300 (2.53 hectares) represents the external drainage area west of Waterloo Street. Catchment 300 encompasses portions of the industrial and residential lands west of the site and drains to the Waterloo Street right-of-way. Catchment 400 (0.65 hectares) represents the portion of the site which currently drains to the existing Trestle Bridge Trail ditch south of the site. Catchment 400 is comprised of vacant land and ground cover is primarily grass and shrubbery. Catchment 401 (0.14 hectares) represents the portion of the site which drains to the existing SWM Pond that was constructed as part of Phase I & II of the Granwood development. Ground cover is primarily grass and shrubbery. Note that this catchment area was accounted for in the design of the Phase I & II SWM Pond.

4.3 Post-Development Conditions

For post-development analysis purposes, the site was modelled as six (6) drainage catchments. The post-development drainage catchments are shown on Figure No. 6 and described below. The post-development MIDUSS computer modeling is attached in Appendix ‘E’.

Catchment 200 (5.04 hectares) represents the northerly portion of the Phase III development which includes the proposed park block. Stormwater runoff from Catchment 200 will be conveyed to the proposed stormwater management facility via the proposed storm sewer system and overland flow routes. Catchment 201 (3.99 hectares) consists of the southerly portion of the Phase III development. Stormwater runoff from Catchment 201 will be conveyed to the proposed stormwater management facility via the proposed storm sewer system and overland flow routes. Catchment 202 (1.22 hectares) consists of the proposed stormwater management facility and surrounding areas. Runoff from Catchment 202 will drain overland to the stormwater management facility. Catchment 300 (2.53 hectares) represents the external drainage area west of Waterloo Street. Catchment 300 will remain unchanged from the pre-development condition and is proposed to drain via the proposed storm sewer and overland to the proposed stormwater management facility. Catchment 500 (0.65 hectares) represents the rear yards of the proposed lots along the south side of Halls Drive. Runoff from Catchment 500 will continue to drain uncontrolled to the existing Trestle Bridge Trail ditch south of the site. Catchment 501 (0.14 hectares) represents a portion of Halls Drive. Catchment 501 will continue to drain to the existing Phase I & II SWM Pond. This catchment area was accounted for in the design of the Phase I & II SWM Pond. The on-site stormwater management facility is proposed to be a wetland facility which will provide quantity control for all storms up to, and including, the 100-year design storm. The stormwater management facility is expected to provide runoff quality control quality for all storms up to, and including, the 2-year design storm.

H

A

L

L

S

D

R

IV

E

Y

O

R

K

S

T

R

E

E

T

E

A

S

T

HA

LL

S D

RIV

E

FIS

HE

R S

TR

EE

T

McNAB STREET

NICHOL STREET

YORK STREET

SOUTH QUEEN STREET

(CLOSED)

C

A

R

T

E

R

P

L

A

C

E

H

A

L

L

S

D

R

IV

E

PARK

PART 1, PLAN

61R-7447

W

A

T

E

R

L

O

O

S

T

R

E

E

T

C

L

A

R

K

E

S

T

R

E

E

T

396.0

0

396.0

0

3

9

7

.

0

0

397.0

0

397.00

3

9

8

.

0

0

398.0

0

3

9

8

.

0

0

3

9

8

.

0

0

3

9

8

.

0

0

399.00

399.0

0

3

9

6

.5

0

396.5

0

3

9

7

.

5

0

3

9

7

.

5

0

3

9

7

.

5

0

3

9

7

.5

0

3

9

7

.

5

0

3

9

8

.

5

0

396.0

0

396.00

397.00

3

9

7

.

0

0

3

9

8

.0

0

3

9

9

.

0

0

3

9

9

.

0

0

399.0

0

3

9

9

.

0

0

3

9

9

.

0

0

4

0

0

.

0

0

4

0

0

.0

0

400.00

396.5

0

396.5

0

3

9

7

.5

0

3

9

8

.5

0

3

9

9

.5

0

3

9

9

.

5

0

3

9

9

.

5

0

3

9

9

.

5

0

3

9

9

.

5

0

400.50

396.0

0

396.00

396.00

3

9

6

.

0

0

3

9

6

.

0

0

396.00

3

9

5

.

5

0

3

9

5

.5

0

3

9

6

.5

0

FIL

E:W

:\G

ue

lp

h\1

14

-2

01

4\1

14

15

2-1

G

ra

nw

oo

d S

WM

R

evie

w\5

W

ork In

P

ro

gre

ss\D

ra

ftin

g\1

14

15

2-G

RA

DIN

G.d

wg

L

AY

OU

T:S

TM

F

IG

P

OS

T D

EV

L

LA

ST

S

AV

ED

B

Y:B

Vla

sm

an, 7

/1

3/2

01

7 9

:4

3:1

3 A

M P

LO

TT

ED

B

Y:B

arry V

la

sm

an

- G

M B

lu

eP

la

n 7

/2

0/2

01

7 2

:2

6:0

0 P

M

030

1:2000

804020

(m)

LEGEND

N

BluePlan

ENGINEERING

114152-1

APRIL 2017


POST-DEVELOPMENT

DRAINAGE AREA PLAN

Figure No. 6

CATCHMENT BOUNDARY

AREA IN HECTARES

CATCHMENT NUMBER

10.13ha.

102

90%

% IMPERVIOUS


EXISTING CONTOURS

PROPOSED MAJOR

OVERLAND FLOW

EXISTING MAJOR

OVERLAND FLOW

GRANWOOD GATE


TOWNSHIP OF CENTRE

WELLINGTON (ELORA)

STORMWATER

MANAGEMENT






JULY 2017

6 OF 8

The wetland facility was designed to meet the Ministry of the Environment (MOE) Stormwater Management Planning and Design Manual design guidelines.

4.3 Routing

The hydrologic model MIDUSS was used to create the runoff hydrographs and to route the flows through the storage structure. The routing results for the proposed on-site stormwater management facility are summarized in Table No. 3 below. Table No. 3: Proposed Stormwater Management Facility - Stage-Storage-Discharge Capacity

Storage and Control

Available Capacity Actual Capacity Used

Peak Flow m³/s

Storage Volume

m³

Storage Elevation

m

Peak Flow m³/s

Storage Volume

m³

Storage Elevation

m

Bottom of Active Storage/ Orifice

0.000 0 392.80 --- --- ---

2-Year --- --- --- 0.018 2,083 393.30

5-Year --- --- --- 0.314 2,504 393.39

100-Year --- --- --- 0.556 5,499 394.00

Weir 0.821 12,135 395.10 --- --- ---

Top of Pond 1.727 13,505 395.30 --- --- ---

A summary of the pre- and post-development peak flow rates to the Waterloo Street stormwater outlet for the 2-, 5- and 100-year design storm events are provided in Table No. 4 below. Table No. 4: Summary of Peak Flow Rates to Waterloo Street Outlet (m

3/s)

2 Year 5 Year 100 Year Pre- Development Peak Flow Rate (m

3/s)

0.248 0.354 0.650

Preliminary Design Capacity of Outlet Storm Sewer (m

3/s)

0.840 0.840 0.840

Post-Development Un-attenuated Peak Flow Rate (m

3/s)

1.286 1.840 3.440

Post- Development Controlled Peak Flow Rate from SWM Facility (m

3/s)

0.018 0.314 0.556

As shown in the above Table No. 4, the post-development peak flow rates to the Waterloo Street outlet are less than the pre-development peak flow rates for the 2-, 5- and 100-year design storm events. The 100-year post-development peak flow rate is also less than the preliminary design capacity of the outlet storm sewer (0.840m

3/s).

A summary of the pre- and post-development peak flow rates to the existing Trestle Bridge Trail ditch south of the site and Phase I & II SWM Pond outlets for the 2-, 5- and 100-year design storm events are provided in Table No. 5 below.






JULY 2017

7 OF 8

Table No. 5: Summary of Peak Flow Rates to the Ditch South of the Site and to the Existing Phase I & II SWM Pond (m

3/s)

Peak Flow Rates to Existing Trestle Bridge Trail Ditch

Peak Flow Rates to Existing Phase I & II SWM Pond

2-Year 5-Year 100-Year 2-Year 5-Year 100-Year Pre- Development Peak Flow Rate (m

3/s)

0.003 0.013 0.077 0.001 0.003 0.017

Post-Development Un-attenuated Peak Flow Rate (m

3/s)

0.063 0.090 0.181 0.018 0.026 0.048

As shown in Table No. 5, the increase in peak flow rates to the existing Trestle Bridge Trail ditch south of the site are minor (0.104m

3/s during the 100-year storm event) and does not require quantity control

measures, as runoff to the ditch will be exclusively from grassed areas and rooftop, and is therefore considered “clean”. As discussed above, the existing Phase I & II SWM was designed to accommodate runoff from Catchment 501, therefore no additional SWM control measures are required for this catchment.

5. WATER QUALITY

Initial water quality treatment on individual lots will begin with roof leader runoff discharging to the surface and allowing the grass cover to provide initial quality treatment. Oil/grit separators will also be utilized as part of the treatment train approach to stormwater quality control. These units will be placed within the storm sewer network prior to discharging to the stormwater management pond. The specific design of these oil/grit separators will be considered at the time of detailed design. Final water quality will be achieved through the proposed on-site stormwater management facility (wetland facility). The 2-year design storm event was used to size the quality control component of the stormwater management facility. As shown in the wetland facility sizing details provided in Appendix ‘F’, the wetland facility is capable of removing 80% of the TSS.

6. ROADWAYS AND GRADING

All proposed roadways are to be developed to full urban standards, with storm sewers, sanitary sewers, watermain, curb and gutter, and street lighting. Sidewalks are proposed on one side of Halls Drive and Harpin Drive, and both sides of York Street. No sidewalks are proposed for Carter Place. Due to the natural easy slope of the lands from east to west, appropriate road grades can be achieved to provide positive drainage towards the SWM facility. Proposed road grades will typically be within the range of 0.5% to 2.0%. Typical proposed lot grades will be within the range of 2.0% to 5.0% in accordance with Township standards.

Appendix A

Preliminary Geotechnical Investigation

Appendix B

Township of Centre Wellington

Preliminary Outlet Storm Sewer Design

M6430A

FOR REFERENCE

M6430A

Appendix C

MIDUSS IDF Curve Fit Modeling

114152-1 Rainfall Distribution Calc 2017-01-13" MIDUSS Output ----------------------------------------------->"" MIDUSS version Version 2.25 rev. 473"" MIDUSS created Sunday, February 07, 2010"" 10 Units used: ie METRIC"" Job folder: W:\Guelph\114-2014\"" 114152-1 Granwood SWM Review\5 Work in Progress\Design Calcs\Modeling Files"" 85 IDF CURVE FIT"" 6 Number of Storms"" 1 Storm no."" 2 Return interval"" 12 Data Pairs"" 5.000 10.000 15.000 30.000 60.000"" 120.000 180.000 240.000 360.000 720.000"" 1080.000 1440.000 minutes"" 9.017 12.367 15.850 20.750 25.600"" 30.800 0.000 0.000 39.000 44.400"" 0.000 52.800 mm"" 108.200 74.200 63.400 41.500 25.600"" 15.400 0.000 0.000 6.500 3.700"" 0.000 2.200 mm/hr"

" 712.297 mm/hr 'A' coeff."" 6.0672 minutes 'B' coeff."

" 0.79552 'C' exponent" " 1.0823 Std.error of estimate"

" 2 Storm no."" 5 Return interval"" 12 Data Pairs"" 5.000 10.000 15.000 30.000 60.000"" 120.000 180.000 240.000 360.000 720.000"" 1080.000 1440.000 minutes"" 11.608 16.500 21.900 30.350 39.200"" 46.000 0.000 0.000 55.200 61.200"" 0.000 69.600 mm"" 139.300 99.000 87.600 60.700 39.200"" 23.000 0.000 0.000 9.200 5.100"" 0.000 2.900 mm/hr"






" 4 Storm no."" 25 Return interval"" 12 Data Pairs"" 5.000 10.000 15.000 30.000 60.000"" 120.000 180.000 240.000 360.000 720.000"" 1080.000 1440.000 minutes"

Page 1

114152-1 Rainfall Distribution Calc 2017-01-13" 15.500 22.700 31.000 44.750 59.700"" 68.600 0.000 0.000 79.800 85.200"" 0.000 96.000 mm"" 186.000 136.200 124.000 89.500 59.700"" 34.300 0.000 0.000 13.300 7.100"" 0.000 4.000 mm/hr"









" 38 START/RE-START TOTALS "" 3 Runoff Totals on EXIT"" Total Catchment area 0.000 hectare"" Total Impervious area 0.000 hectare"" Total % impervious 0.000"" 19 EXIT"

Page 2

Appendix D

Pre-Development MIDUSS Computer Model Output for the 2-, 5- and 100-Year Design Storms

Appendix E

Post-Development MIDUSS Computer Model Output for the 2-, 5- and 100-Year Design Storms and Stage-Storage Discharge Calculation Tables

Surface Perm. Pool Accum. P.P. Surface Active Accum. Active

Elevation Depth Area Volume Volume Area Volume Volume

(m) (m) (m2) (m3) (m3) (m2) (m3) (m3)

391.50 0.00 381.00 0.00 0.00

391.60 0.10 487.00 46.84 46.84

391.70 0.20 526.00 50.67 97.51

391.80 0.30 565.00 54.56 152.07

391.90 0.40 605.00 58.53 210.60

392.00 0.50 646.00 62.56 273.16

392.10 0.60 687.00 66.64 339.80

392.20 0.70 729.00 70.81 410.61

392.30 0.80 772.00 75.03 485.64

392.40 0.90 815.00 79.32 564.96

392.50 1.00 3148.00 83.67 648.63 Top of Forebay

392.60 1.10 3322.00 323.57 972.20

392.70 1.20 3488.00 340.53 1312.73

392.80 0.00 3692.00 356.76 1669.49 3692.00 0.00 0.00 Permanent Pool

392.90 0.10 3842.00 376.67 376.67

393.00 0.20 4161.00 400.64 777.31

393.10 0.30 4274.00 421.77 1199.08

393.20 0.40 4388.00 433.09 1632.17

393.30 0.50 4502.00 444.50 2076.67 Extended Detention

393.40 0.60 4618.00 455.98 2532.65

393.50 0.70 4734.00 467.57 3000.22

393.60 0.80 4851.00 479.24 3479.46

393.70 0.90 4969.00 490.99 3970.45

393.80 1.00 5088.00 502.83 4473.28

393.90 1.10 5207.00 514.75 4988.03

394.00 1.20 5328.00 526.76 5514.79

394.10 1.30 5449.00 538.87 6053.66

394.20 1.40 5572.00 551.06 6604.72

394.30 1.50 5696.00 563.38 7168.10

394.40 1.60 5821.00 575.84 7743.94

394.50 1.70 5948.00 588.43 8332.37

394.60 1.80 6075.00 601.14 8933.51

394.70 1.90 6205.00 613.98 9547.49

394.80 2.00 6335.00 626.96 10174.45

394.90 2.10 6467.00 640.07 10814.52

395.00 2.20 6600.00 653.30 11467.82

395.10 2.30 6734.00 666.66 12134.48 Weir

395.20 2.40 6859.00 679.75 12814.23

395.30 2.50 6953.00 690.74 13504.97 Top of Pond

Q = 0.014 m3/s Q = 0.861 m3/s d1 = 2.50 m

Cd = 0.600 Cd = 0.600 h = 2.30 m

H = 0.450 m H = 2.238 m H = 0.20 m

2g = 19.620 2g = 19.620 2g = 19.62

L = 7.00 m

A = 0.008 m2 A = 0.216 m2

D = 0.100 m D = 0.525 m Q = 0.87 m3/s

Granwood Subdivision

Township of Centre Wellington

GMBP File: 114152-1

Stormwater Management Pond

Storage Volume Calculations

Orifice (Quality) Orifice (Quantity) Overflow Weir

(392.80 m) (393.20 m) (395.10 m)

Elevation Stage Storage 300 mm Orifice 525mm Orifice Overflow Weir Total Discharge

392.80m 393.3 395.10m

(m) (m) (m3) (m3/s) (m3/s) (m3/s) (m3/s)

392.80 0.00 0.0 0.000 0.000 Permanent Pool

392.90 0.10 376.7 0.004 0.004

393.00 0.20 777.3 0.008 0.008

393.10 0.30 1,199.1 0.010 0.010

393.20 0.40 1,632.2 0.012 0.012

393.30 0.50 2,076.7 0.014 0.000 0.014 Extended Detention

393.40 0.60 2,532.7 0.334 0.334

393.50 0.70 3,000.2 0.381 0.381

393.60 0.80 3,479.5 0.422 0.422

393.70 0.90 3,970.5 0.459 0.459

393.80 1.00 4,473.3 0.494 0.494

393.90 1.10 4,988.0 0.527 0.527

394.00 1.20 5,514.8 0.557 0.557

394.10 1.30 6,053.7 0.586 0.586

394.20 1.40 6,604.7 0.614 0.614

394.30 1.50 7,168.1 0.640 0.640

394.40 1.60 7,743.9 0.665 0.665

394.50 1.70 8,332.4 0.690 0.690

394.60 1.80 8,933.5 0.713 0.713

394.70 1.90 9,547.5 0.736 0.736

394.80 2.00 10,174.5 0.758 0.758

394.90 2.10 10,814.5 0.780 0.780

395.00 2.20 11,467.8 0.801 0.801

395.10 2.30 12,134.5 0.821 0.000 0.821 Weir

395.20 2.40 12,814.2 0.841 0.303 1.145

395.30 2.50 13,505.0 0.861 0.867 1.727 Top of Pond

Stormwater Management Pond

Stage-Storage-Discharge Table

Appendix F

Wetland Facility Sizing Details

Project No. 114152-1

Project: Granwood Gate Subdivision, Phase III

Date: May 12, 2017

Designer: Adrien French

Stormwater Management Facility Quality Sizing:

The stormwater management facility has been designed to function as a wetland. From Table 3.2 of the MOE Stormwater Management Planning and Design Manual, 2003, in order to provide Enhanced water quality treatment (80% TSS Removal), a wetland facility requires:

105m³/ha of quality storage volume for a contributing drainage area that is approximately 55% impervious.

40m³/ha of the required quality storage volume is extended detention volume, while the remaining is permanent pool.

Calculating the total required quality volume:

Total contributing drainage area = 12.82ha

Combined imperviousness of contributing area = 53% (assume 55% for quality sizing purposes)

Quality Storage Requirement = 105m3/ha = 1,346m

3

Calculating Extended Detention Volume:

Extended Detention Requirement = 40m3/ha for site and external areas

Required Extended Detention Volume = 513m3

Calculating Permanent Pool Volume:

Required Permanent Pool Volume = Total Quality Volume – Extended Detention Volume

Required Permanent Pool Volume = 833m3

Alternative Extended Detention Sizing:

Given that the 2 year storm has been used as the quality sizing event for this facility, the extended detention volume is required to store at a minimum the full capacity of the 2-year design storm.

From the MIDUSS modeling, the 2-year design storm requires a maximum storage volume of approximately 2,077m

3, which correspond to an elevation of 393.30m. The Extended Detention orifice

has therefore been set at an elevation of 393.30m.

A summary of the quality sizing volumes are provided in Table No. E-1 below:

Table No. E-1: Quality Sizing Volumes Summary

Required Provided

Extended Detention Volume 2,077m3

2,077m3

Permanent Pool Volume 833m3

1,669m3

Total Quality Volume 1,346m3 3,746m

3

Sediment Forebay Design

The Sediment forebay has been designed to meet the MOE Stormwater Management Planning and Design Manual requirements for wetland facilities. The design of the forebay is summarized in Table No. E-2 below:

Table No. E-2: Forebay Design Details

Forebay

Required

Settling Length (m) 13.8

Dispersion Length (m) 29.0

Flow Velocity (m/s) 0.15

Length to Width Ratio 2:1

Settling Velocity (m/s) 0.0003

Provided

Forebay Length (m) 90.0

Flow Velocity (m/s) 0.07

Length to Width Ratio 4:1

edgehill properties limited c/o ... - centre wellington · stormwater management block, as shown on...

Documents