PRELIMINARY CIVIL ENGINEERING SERVICES REPORT Zicht/Draft Amen… · preliminary civil engineering services report for the provision of roads and civil engineering services for de

PRELIMINARY CIVIL ENGINEERING SERVICES REPORT

FOR THE

PROVISION OF ROADS AND

CIVIL ENGINEERING SERVICES FOR DE ZICHT

RESIDENTIAL DEVELOPMENT

ERF 36555 & 2, MILNERTON, CAPE TOWN SEPTEMBER 2017 REVISION 1 PREPARED FOR: PREPARED BY:

Balwin Properties Limited Bau-afrika (Pty) Ltd Property Developers Consulting Engineers Private Bag X13 P O Box 2950 Bertham Durbanville 2013 7551 TEL: (011) 680-4551 TEL: (021) 975-6073 FAX: (086) 578-4661 FAX: 088 (021) 976-7500

2

II TABLE OF CONTENTS

_________________________________________________________________________ NO. DESCRIPTION PAGE I QUALITY CERTIFICATE 1 II TABLE OF CONTENTS 2 1 INTRODUCTION 3 2 STUDY AREA 3 3 SITE DESCRIPTION 5 4 EXISTING CIVIL ENGINEERING SERVICES 7

4.1 EXISTING STORMWATER 7 4.2 EXISTING SEWER 7 4.3 EXISTING WATER 9 4.4 EXISTING ROADS AND ACCESS 9 4.5 BULK SERVICE CONNECTIONS & RELOCATION 9

5 PROPOSED STORMWATER 12 5.1 PRE- DEVELOPMENT FLOWS 12 5.2 POST- DEVELOPMENT FLOWS 12 5.3 MINOR SYSTEM 16 5.4 MAJOR SYSTEM 17

6 PROPOSED SEWER 24 6.1 ASSUMPTIONS FOR SEWER MODELLING 24 6.2 SEWER MODELLING RESULTS 24 6.3 SEWER PROPOSAL 26

7 PROPOSED WATER 27 7.1 ASSUMPTIONS FOR WATER MODELLING 27 7.2 WATER MODELLING RESULTS 28 7.3 WATER PROPOSAL 28

8 ROADS, ACCESS AND PARKING 29 8.1 ACCESS 29 8.2 INTERNAL NETWORK 29

9 TELECOMMUNICATION 29 10 ELECTRICAL 29 11 SOLID WASTE MANAGEMENT 30 12 CONCLUSIONS 33

III LIST OF REFERENCES 34

3

1 INTRODUCTION

This report summarises the requirements for providing roads and civil engineering services for the proposed residential development on Erf 36555 & 2 known as De Zicht, Milnerton in Cape Town.

Information in this report was obtained from the following sources:

De Zicht Overall Site Plan – July 2017, DHK Architects (Pty) Ltd

Geotechnical Investigation of De Zicht, Erf 36555 – April 2017, Core

Geotechnical Consultants As-built Drawings for the development of Annandale Ridge, Erf 36555 –

July 2015, Aurecon Consulting Engineers Topographical survey of De Zicht and surrounding areas – April 2017,

Joubert & Brink Surveys

Traffic Impact Assessment of De Zicht – April 2017, HHO Infrastructure Engineers

2 STUDY AREA De Zicht is a 9.65ha residential development on Erf 36555 & Erf 2 and is located north of the existing Richwood suburb situated adjacent to the N7 highway in Milnerton. The site is bounded by: West – N7 (National Road), which is a dual carriage highway through

Milnerton suburb linking Cape Town to towns along the West Coast and Northern Cape.

East – Warren Way, a local road along the site boundary. South – The residential suburb of Richwood, Milnerton North – The future road reserve for extending Blaauwberg Road in Table

View, across the N7 and linking it with roads heading to Durbanville suburb. The first phase known as Phase ‘A’, De Zicht has been approved for development on 25 July 2017. The approved Site Development Plan permits the construction of 4 storey apartment blocks on 1.95ha of land located along the northern boundary of the site. Phase ‘A’ will accommodate 180 apartment units with a parking provision of 242 bays. (Refer to Diagram 2: Site Locality Plan on page 4)

ERF 36555

DUNOON

KILLARNEYGARDENS

LA M ONT CLOSE

WOO

DLA

ND

S D

RIV

E

WOO

DLA

ND

S D

RIV

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MIDWOOD CLOSE

JONKERSHOEK ROAD

ANNANDALE DRIVE

SIENNA DRIVE

INDIGO DRIVE

WA

RR

EN

BLAAUWBERG ROAD EXTENSION

TYG

ER

BER

G V

ALLE

Y R

OA

D

CARM

INE D

RIVE

SYLVIA

RICHWOOD

BURGUNDYESTATE

RICHMONDPARK

CHEVRONREFINERY

CRUDE TANKS

ATLANTICHILLS

CESAConsulting Engineers South Africa

Bau-afrikaConsulting Engineers & Project Managers

P.O. Box 2950 tel: +27 21 975 6073 / fax: +27 21 976 7500Durbanville 7551 [email protected] Africa www.bau-afrika.co.za

DIAGRAM 2

SCALE 1:10000

SITE LOCALITY PLAN

TY

GE

RB

ER

G V

AL

LE

Y R

OA

DN7 H

IGH

WA

Y

N7 H

IGH

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Y

RA

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PO

TSD

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BLAAUWBERG ROAD EXTENSIO

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ERF 2

PHASE 'A'DE ZICHT

5

3 SITE DESCRIPTION

Based on the available information, the following site characteristics are summarised: The site slopes from east & northeast, towards west & southwest and has an

average gradient of 3.5%

The existing site is fully serviced with utilities and roads to accommodate the previous site plan consisting of single residential, semi-detached and group housing units.

The redevelopment of the site will as far as possible utilise the existing services

to accommodate the new site development proposal. The site consists of sandy soils up to 1 meter below natural ground level and

becomes clayey sand the deeper the excavation (Between 1.2 to 2.7m deep) Uncontrolled surface fill has occurred over the site, which is moderately

compressible and contains waste or rubble. This material is unsuitable for construction use or founding purposes.

The geotechnical investigation found residual shale soils consisting of stiff to

very stiff clayey silt up to 2.7m deep.

Perched ground water was not encountered in any excavated areas but can be anticipated within the sandy soil layer during winter months for excavations within 1m to 2m in depth.

External stormwater catchment areas discharge onto the De Zicht site and need to be accommodated or redirected around the site.

The site development proposal allows for 73 four storey apartment blocks,

consisting of 12 units per block with the developed site totalling 876 units. The development of the site proposes the construction of apartment blocks in

10 phases. Phase ‘A’, De Zicht encompasses Phases 1 and 2 of the development.

(Refer to Diagram ‘3’: Site Plan on page 6)

SWPOND

SW

AL

E

SWPOND

LPGAS

ENTRANCE

CL

UB

HO

US

E

12

34

56

7

8

9

SO

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10

12

11

5051 4948 47

42 43

525357596164 63 62

37383940

27

262523 24

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72 73 66

67

6558

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31 30 29 28

46

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MORRIS SHELL DRIVE

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LIMPET CRESCENT

LIM

PE

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LIMPET CLOSE

LIMPET STREET

CH

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WA

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FUTURE BLAAUWBERG ROAD EXT.

SYLVIA STREET

JETTA SHELL WAY

EXIST. REGIONALSTORMWATERDETENTION POND

EXIST. SEWERPUMP STATION

SCALE 1:1500

DIAGRAM 2DE ZICHT

SITE PLAN



Consulting Engineers South Africa

CESA

ASPHALT SURFACINGTO ENGINEER DETAILS

LANDSCAPED AND OPEN AREAS

BRICK PAVED SURFACINGTO LANDSCAPE DETAILS

BIO-RETENTIONAREA

RICHWOOD

PHASE 2

PHASE 1

PHASE 3

PHASE 4

PHASE 5PHASE 4

PHASE 6

PHASE 7

PHASE 8

PHASE 9

PHASE 10

7

4 EXISTING CIVIL ENGINEERING SERVICES

Refer to the existing site plan for existing service locations.

(Refer to Diagram 4a: Existing Site Service Layout on page 8)

4.1 EXISITNG STORMWATER Stormwater runoff from the site accumulates within the existing internal road network provided with kerbs, channels and stormwater catchpits. The following is to be noted: The existing site’s pipe system is sized to accommodate the previous

development runoff for storms up to 1:2 year RI. (Aurecon, 2010)

The road network has a localised low point located in the north western

corner of the site and is provided with a bulk stormwater catchpit sized to intake up to 1:50 year RI. (Aurecon, 2010)

All stormwater is routed within a 1200 x 900 box culvert that crosses the future road reserve, north, and discharges into a wet extended detention pond constructed with a clay lining to encourage permanent pooling. (Aurecon, 2010)

The subdivided Erf 36555 is provided with a stormwater pipe network

consisting of various sizes ranging from ø300mm to ø525mm. (Aurecon, 2010)

The stormwater runoff linked to the road network is routed to a regional

detention facility sized to accommodate the following stormwater requirements: - Water Quality Volume (WQV) = 5040m³ - Extended detention over a 24hr period to satisfy channel protection

volume (CPV) - The permanent pooling in the pond = up to 1.5m depth before

discharging at the outlet headwall (Aurecon, 2010)

The existing site As-builts are available on request.

4.2 EXISTING SEWER

The subdivided Erf 36555 is provided with an ø160mm sewer pipe network complete with erf connections and discharges into an ø200mm bulk sewer main at the north western corner of the site. The bulk sewer is routed to the existing municipal sewer pump station located North West of the site and pumps in a south westerly direction to the Potsdam Wastewater Treatment Works within an ø350mm sewer rising main at the western site boundary. Refer to Diagram 4a on page 8.

ø160m

m F

S

1:3

0.2

ø200m

m F

S

ø350m

m F

S

ø200mm FS

ø160mm FS

ø160m

m F

S

ø160mm FS

ø160mm FS

BE

RG

ZIC

HT

RO

AD

MORRIS SHELL DRIVE

UITZICH

BE

RG

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MORRIS SHELL DRIVE

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LIMPET CRESCENT

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LIMPET CLOSE

LIMPET STREET

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EN

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SYLVIA STREET

JETTA SHELL WAY

FOREBAY

ø375 SW

ø375 S

W

ø450 SW

1200x

900 B

C

1200x900 B

C

FOREBAY

PERMANENT POOL

ø750m

m S

W

AQUATICBENCH

ø750m

m S

W

ø450m

m B

UL

K W

M

ø40m

m W

M C

onn.

V

HV

V

VH

V

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V

V

V

H

H

H

H

H

V

V

H

V H

H

AV

V

V


ø350m

m S

EW

ER

RM

ø450mm BULK WM


ø40

0mm

BU

LK

WM

V

ø450mm BULK WMH

V

Vø200mm WM

ø160m

m W

M

ø110m

m W

M

ø160 W

M

ø160m

m W

M

ø110mm WM

ø160m

m W

M

ø160 W

M

ø160mm WM

ø110mm WMø110mm WM

ø110m

m W

M

ø375 SW

ø450 SW

ø375 SW

ø525 SW

ø525 SWV

ø375 SW

ø160m

m F

S

ø110 W

M

ø160mm FS

EXISTING BULK WATER

EXISTING STORMWATER

EXISTING WATER

EXISTING SEWER

LEGEND (EXISTING SERVICES):

SCALE 1:1500

DIAGRAM 4aDE ZICHT

EXISTING SITESERVICES LAYOUT




CESA

V

VH

9

4.3 EXISTING WATER Along existing internal roads, an ø160mm uPVC watermain loops from the adjacent Richwood suburb and ties in to an ø400mm ductile watermain along Carmine Drive as an ø200mm pipe. The ø160mm pipes as well as ø110mm link pipes complete with water erf connections service the subdivided Erf 36555. An ø450mm bulk watermain traverses the site and is the supply line for the Du Noon and Killarney Gardens development areas. Refer to Diagram 4a on page 8.

4.4 EXISTING ROADS AND ACCESS

An existing two-way road known as Carmine Drive intersects off Tygerberg Valley Road and provides an access route to the subdivided Erf 36555. Two-way link roads also enter the site from the south as extension roads from the Richwood residential suburb. The existing roads extend Abalone Street (to the east) and Oyster Street (to the west). Refer to Diagram 4a on page 8.

4.5 BULK SERVICE CONNECTIONS AND RELOCATION

The development of De Zicht, Milnerton will make use of existing service connections and where possible incorporate the existing pipe reticulations as part of the redevelopment of the site. For Phase ‘A’, De Zicht the following service construction is proposed, while the existing ø450mm bulk watermain is relocated around the proposed development. (Refer to Diagram 4b: Phase ‘A’ De Zicht Services Plan on page 10) For the full development of the site, the following existing services are retained and relocated for the further development of De Zicht. (Refer to Diagram 4c: Bulk Service Connections & Relocation on page 11)

MICROPOOL

AQUATICBENCH

1:3

0.2

RE

TA

IN E

X. ø

200m

m F

S

ø350m

m F

S

EX. ø200mm FS

EX. ø160mm FS

EX

. ø

160m

m F

S

EX. ø160mm FS

EX. ø160mm FS

NEW ø450mm PIPE TO BEINSTALLED FOR FUTURE USE

NEW STORMWATER MANHOLETO BE CONSTRUCTED OVER EX.ø375mm PIPE WITHOUT BENCHING

ø300mm SW

ø375mm SW

ø450mm

ø300m

m

ø450m

m

NEW ø600mm PIPE TO BEINSTALLED & END CAPFOR FUTURE USE

RELAY EX. 1200x900 BCTO CONSTRUCT PONDOUTLET STRUCTURE

INSTALL NEW ø375mm PIPE ANDCONNECT TO EX. SW MANHOLE

RELOCATEDø450mm BULK WM

RELOCATEDø450mm BULK WM

ø450mm BULK WMTHROUGH PIPE SLEEVE

BE

RG

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HT

RO

AD

MORRIS SHELL DRIVE

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BE

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MORRIS SHELL DRIVE

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CL

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LIMPET CRESCENT

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LIMPET CLOSE

LIMPET STREET

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EN

WA

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SYLVIA STREET

JETTA SHELL WAY

FOREBAY

EX. ø375 SW

RE

TA

IN E

X. ø

375 S

W

EX. ø450 SW

RE

TA

IN E

X. 1

200x900 B

C

FOREBAY

PERMANENT POOL

ø750m

m S

W

AQUATICBENCH

ø750m

m S

W

EX

. ø450m

m B

UL

K W

M EX

. ø40m

m W

M

TO

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AB

AN

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EX

. ø

350m

m S

EW

ER

RM

EX. ø450mm BULK WMTO BE RELOCATED


EX

. ø400

mm

BU

LK

WM

VH

V

VEX. ø200mm WM

EX

. ø160m

m W

M

RE

TA

IN E

X. ø

110m

m W

M

EX. ø110mm WM

EX

. ø

160m

m W

M

EX

. ø

160 W

M

EX. ø160mm WM

EX. ø110mm WMEX. ø110mm WM

EX

. ø

110m

m W

M

EX. ø375 SW

RETAIN EX. ø450 SW

EX. ø375 SW

EX. ø525 SW

ø525 SWV

EX. ø375 SW

RE

TA

IN E

X. ø

110 W

M

EX. ø160mm FS

RETAIN EX. ø160mm FS

23

45

6

7

8

9

10

12

11

15

16

13

1

EX

. ø

160m

m W

M

EX

. ø

160 W

M

EX. ø450mm BULK WMTO BE RELOCATED

EX

. CU

LVE

RT T

O

BE

RE

MO

VE

D

CONNECT NEW ø200mmTO EX. ø200mm PIPE

ø200mm FS

ø160mm

EX. ø160mm PIPE TO BE REMOVED& REPLACED WITH NEW SEWER PIPEFOR FUTURE USE

ø450mm

ø600mm SW

PRE-TREATMENT

FOREBAY

BM

H V

H

H

H

H

V

V

V

V

V

V

V

V

V

V

VH

H

ø160mm FS

ø160mm FS

ø110mm WM

ø110m

m W

M

ø110m

m W

M

ø110mm WM

NEW ø110mm WATERCONNECTION TOEX. ø110mm PIPE

ø110mm WATEREND CAPS FORFUTURE USE

ø110mm WATEREND CAPS FORFUTURE USE

POND '1'

SV

V

V

AV

SCALE 1:1500

DIAGRAM 4bDE ZICHT

PHASE 'A' SITESERVICES LAYOUT




CESANEW STORMWATER

EXISTING SEWER

EXISTING WATER

EXISTING VALVES & HYDRANTS

EXISTING BULK WATER

NEW SEWER

WATER PIPES, VALVES,HYDRANTS & END CAPS

BULK WATER METER

EXISTING STORMWATER

MHCP

BM

H V

LEGEND (NEW SERVICES):


H V

V

END CAP TO EX.ø450mm BULK WM

CONNECT ø40mm WATERTO NEW SCOUR VALVEON RELOCATED WM

MICROPOOL

AQUATICBENCH

1:3

0.2

RE

TA

IN E

X. ø

200m

m F

S

ø350m

m F

S

ABANDONED EX. ø160mm FS

NEW ø450mm PIPETO REDIRECT SW

SW MANHOLE BENCHINGTO BE ALTERED TOREDIRECT SW FLOW

ø300mm SW

ø375mm SW

ø450mm

ø300m

m

ø450m

m

ø600mm PIPE ENDFOR FUTURE USE

NEW ø375mm SW PIPE& MANHOLES TO REDIRECTSW ALONG WARREN WAY

ø450mm BULK WM

ø450mm BULK WM


BE

RG

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MORRIS SHELL DRIVE

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MORRIS SHELL DRIVE

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LIMPET CRESCENT

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LIMPET STREET

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SYLVIA STREET

JETTA SHELL WAY

FOREBAY

RE

TA

IN E

X. ø

375 S

W

RE

TA

IN E

X. 1

200x900 B

C

FOREBAY

PERMANENT POOL

ø750m

m S

W

AQUATICBENCH

ø750m

m S

W

EX

. ø450m

m B

UL

K W

M

V

HV

V

VH

V

V

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H

H

H

H

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V

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V H

H

AV


EX

. ø

350m

m S

EW

ER

RM

EX. ø450mm BULK WMABANDONED


EX

. ø400

mm

BU

LK

WM

H

V

EX. ø200mm WM

EX

. ø160m

m W

M

RE

TA

IN E

X. ø

110m

m W

M

V

23

45

6

7

8

9

10

12

11

15

16

13

1

EX. ø450mm BULK WMABANDONED

ø200mm FS

ø160mm

NEW ø160mm PIPEFOR FUTURE USE

ø450mm

ø600mm SW

PRE-TREATMENT

FOREBAY

BM

H V

H

H

H

H

V

V

V

V

V

V

V

V

V

V

VH

H

ø160mm FS

ø160mm FS

ø110mm WM

ø110m

m W

M

ø110m

m W

M

ø110mm WM

ø110mm WATERSUPPLY OFF EX.ø110mm PIPE

ø110mm WATER ENDFOR FUTURE USE

ø110mm WATER ENDFOR FUTURE USE

POND '1'

SV

V

V

AV

SCALE 1:1500

DIAGRAM 4cDE ZICHT

BULK SERVICE CONNECTIONS& RELOCATION




CESANEW STORMWATER

EXISTING SEWER

EXISTING WATER

EXISTING VALVES & HYDRANTS

EXISTING BULK WATER

NEW SEWER

WATER PIPES, VALVES,HYDRANTS & END CAPS

BULK WATER METER

EXISTING STORMWATER

MHCP

BM

H V

LEGEND (NEW SERVICES):


H V

V

END CAP EX.ø110mm WM



V



V

V


V

V H

ROAD ACCESS TOPHASE 1 TO BERETAINED

EXISTING WATER, SEWER &STORMWATER SERVICES TOBE REMOVED OR ABANDONEDFOR REDEVELOPMENT OF SITE

NEW 4.5m SERVICESSERVITUDE TO BEREGISTERED

GABIONS

GABIONS

GABIONS

INLETSTRUCTURE

GABIONS

SILT TRAP

NEW SW DRAIN COMPLETEWITH CHECK DAMS & SILT TRAPFOR MANAGING EXTERNAL SW

EXISTING ROAD TOBE ALTERED TO SUITE

EXISTING ROAD SURFACING& LAYERWORKS TO BE REMOVED& STOCKPILE FOR FUTURE USE

12

5 PROPOSED STORMWATER

5.1 PRE-DEVELOPMENT RUNOFF The runoff for the pre-developed site was calculated by using the following hydrological and hydraulic parameters: Stormwater modelling: EPA-SWMM version 5 Build 5.0.021

Design storms: City’s Design Rainfall Depth Grid

At grid position 33°50’ Latitude; 18°33’ Longitude (closest position to De Zicht)

Design storms of 1:½ (interpolated), 1:1(interpolated), 1:2, 1:5, 1:10, 1:20, 1:50 and 1:100 year return intervals (RI) was simulated by using a SCS Type-1 storm over 24hrs having a rainfall depth of 20mm (interpolated), 27mm (interpolated), 47mm, 63mm, 75mm, 87mm, 104mm and 118mm respectively.

Soil Infiltration Method: Green-Ampt assuming a soil texture class of sandy loam based on the geotechnical study’s description of sandy material across the site.

Routing method: Dynamic Wave as per EPA-SWMM modelling

The catchment areas and names are based on the Proposed Stormwater Drainage Configuration in Diagram 5a for existing site conditions prior to the roads and services installed as described in Section 3 of this report. Note that Richwood development does not drain towards the site and is not to be accommodated. (Refer to Diagram ‘5a’: Proposed Stormwater Drainage Configuration on page 13) The pre-development stormwater modelling results are provided in Table 5a. (Refer to Table ‘5a’: Pre-Development Stormwater Modelling Results on page 14)

5.2 POST DEVELOPMENT RUNOFF

The runoff for the post-developed site was calculated by altering the catchment parameters to include for the construction of apartment blocks and surfacing of previously natural ground covered areas. The impervious areas consist of proposed building footprints, proposed road and parking areas. The percentage impervious area per catchment is provided with post development results.

The un-attenuated Post development stormwater modelling results are provided in Table 5b.

(Refer to Table ‘5b’: Post Development Stormwater Modelling Results on page 15)

MICROPOOL

AQUATICBENCH

C-'A'

C-'B'

C-'EXT'

C-'C'

BE

RG

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HT

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AD

MORRIS SHELL DRIVE

UITZICH

BE

RG

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RO

AD

ANNANDALE DRIVE

MORRIS SHELL DRIVE

CO

CK

LE

CL

OS

E

LIMPET CRESCENT

LIM

PE

T S

TR

EE

T

LIMPET CLOSE

LIMPET STREET

CH

ITT

EN

WA

Y

OY

ST

ER

ST

RE

ET

AB

AL

ON

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TR

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T

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EX

T.

WA

RR

EN

WA

Y


SYLVIA STREET

JETTA SHELL WAY

FOREBAY

RE

TA

IN E

X. 1

200x900 B

C

FOREBAY

PERMANENT POOL

ø750m

m S

W

AQUATICBENCH

ø750m

m S

W

2

45

6

7

8

9

11

1

PRE-TREATMENT

FOREBAY

POND '1'

SW DRAIN COMPLETE WITHCHECK DAMS & SILT TRAP FORMANAGING EXTERNAL SW

LPGAS

REFUSEYARD

ENTRANCE

CL

UB

HO

US

E

SO

CC

ER

42 43

70

71

72 73

46

44

41

RE

FU

SE

PA

RK

ING

POOL

HP

HP

HP

HP

HP

HP

HP

HP

HP

HP

HP

PRE-TREATMENT

FOREBAY

BIO-RET. '1'

EN

HA

NC

ED

SW

AL

E

SW-EXT'1'OVERLAND ESCAPEWITH LARGE INTAKEGRID-INLET CATCHPIT

GI-2

GI-7

GI-5

GI-41

GI-8

GI-10GI-11

GI-13

GI-20

GI-34

HW-35

GI-25

GI-69

GI-29

GI-38

GI-36

GI-46GI-47GI-48

GI-67 GI-64

GI-76

GI-80

POND '2'

AQUATICBENCH

MICROPOOL

262523 24

32

5759 58

69

67

68

272831 30 29

SCALE 1:1500

DIAGRAM 5aDE ZICHT

PROPOSED STORMWATERDRAINAGE CONFIGURATION




CESA

45GI-62

48 475051 495253

55

56

54

HW-71

HW-82

22

21

3

19

20

3433

3738394036

35

16

13

14

GI-50

10

18

17

12

15

606164 63 6265

66

ha

mm

%%

%A

/ B

8.60

362

1.5

138.

423

2.81

6-

-C

1.00

494

.810

5.90

72.

110

--

EX

T1.

398

157.

788

.672

1.12

0-

-

m³

m³/

sm

³m

³/s

m³

m³/

sm

³m

³/s

m³

m³/

sm

³m

³/s

m³

m³/

sm

³m

³/s

A /

B0.

00.

000

0.0

0.00

00.

00.

000

40.0

0.04

011

5.0

0.06

621

4.0

0.11

742

1.0

0.25

964

5.0

0.40

7C

0.0

0.00

00.

00.

000

0.0

0.00

011

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007

34.0

0.01

865

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032

116.

00.

056

163.

00.

080

EX

T0.

00.

000

0.0

0.00

00.

00.

000

0.0

0.00

00.

00.

000

2.0

0.00

323

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029

50.0

0.05

6

Slo

pe

Imp

C m

ent

Are

aF

low

L

eng

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men

t W

idth

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1:1y

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2yr

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1:50

yr R

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un

off

Pea

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To

tal

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no

ff

1:5y

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no

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Ru

no

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un

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Pea

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To

tal

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ff

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b:

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ST

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MW

AT

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MO

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RE

SU

LT

S

DE

ZIC

HT

: P

RE

-Dev

elo

pm

ent

Ru

no

ff S

um

mar

y

1:½

yr R

IT

ota

l R

un

off

Pea

k R

un

off

1:10

yr R

I1:

20yr

RI

To

tal

Ru

no

ffP

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Ru

no

ff

DE

ZIC

HT

: P

RE

-Dev

elo

pm

ent

Geo

met

ric

Par

amet

ers

C m

ent

Zer

o

Imp

1:10

0yr

RI

To

tal

Ru

no

ffP

eak

Ru

no

ffT

ota

l R

un

off

Pea

k R

un

off

ha

mm

%%

%GI-2

0.231

71.2

32.490

4.492

76.06

23.20

GI-5

0.381

81.8

46.641

1.957

76.89

22.93

GI-7

0.314

77.4

40.559

1.938

76.14

30.36

GI-8

0.283

79.9

35.449

2.252

73.96

30.89

GI-10

0.164

42.7

38.380

2.109

82.24

31.90

GI-11

0.145

56.5

25.584

2.299

81.73

23.03

GI-13

0.200

51.0

39.258

0.980

76.44

19.76

HW-35

0.209

14.2

146.548

0.500

8.11

86.14

GI-20

0.357

100.5

35.539

3.185

59.14

23.12

GI-29

0.236

65.9

35.896

3.037

68.17

19.02

GI-34

0.594

45.0

38.546

2.660

59.85

34.08

GI-46

0.254

84.6

29.972

2.837

73.90

28.01

GI-50

0.449

95.8

46.809

2.400

71.79

33.27

GI-76

0.270

79.3

34.036

1.892

81.42

24.79

GI-80

0.409

105.3

38.847

2.849

71.03

22.10

GI-36

0.760

38.8

45.395

3.607

67.59

33.55

GI-38

0.287

83.0

34.643

3.375

75.57

30.93

GI-41

0.703

133.6

52.621

3.593

74.14

21.90

HW-71

0.531

53.1

99.892

1.130

49.11

36.63

GI-62

0.409

99.1

41.221

5.650

64.43

30.47

GI-64

0.448

120.2

37.216

5.738

76.58

13.67

GI-67

0.457

110.0

41.543

3.820

71.02

36.03

GI-69

0.512

50.8

100.777

0.984

48.39

64.60

CHW-82

1.004

94.8

105.907

2.110

70.07

30.05

EXT

SW-X5

1.398

157.7

88.672

1.120

13.87

-

m³

m³/

sm

³m

³/s

m³

m³/

sm

³m

³/s

m³

m³/

sm

³m

³/s

m³

m³/

sm

³m

³/s

GI-2

28.3

0.010

40.6

0.010

75.7

0.020

103.9

0.030

198.9

0.060

146.1

0.040

175.9

0.050

200.8

0.060

GI-5

46.8

0.010

67.3

0.020

125.7

0.030

172.5

0.050

330.6

0.090

242.7

0.060

292.4

0.080

333.6

0.090

GI-7

39.1

0.010

55.8

0.010

103.5

0.030

141.7

0.040

280.9

0.080

201.6

0.050

246.4

0.070

283.5

0.080

GI-8

34.4

0.010

49.0

0.010

90.8

0.020

124.3

0.030

247.5

0.070

177.1

0.050

216.8

0.060

283.5

0.080

GI-10

22.2

0.010

31.6

0.010

58.6

0.020

80.1

0.020

157.1

0.050

113.5

0.030

138.2

0.040

249.8

0.070

GI-11

19.0

0.010

27.2

0.010

50.8

0.010

69.7

0.020

137.3

0.040

99.1

0.030

120.7

0.040

138.6

0.040

GI-13

24.2

0.010

34.9

0.010

65.4

0.020

89.8

0.020

178.8

0.050

128.2

0.030

156.8

0.040

180.5

0.050

HW-35

3.3

0.000

4.4

0.000

7.8

0.000

10.5

0.000

45.1

0.020

20.9

0.010

34.2

0.010

46.0

0.020

GI-20

33.9

0.010

48.6

0.010

90.8

0.020

124.5

0.030

238.6

0.070

175.1

0.050

167.7

0.050

240.8

0.070

GI-29

25.6

0.010

36.8

0.010

69.0

0.020

94.7

0.030

192.1

0.060

136.1

0.040

211.0

0.060

194.0

0.060

GI-34

65.2

0.010

90.1

0.010

161.4

0.020

220.7

0.030

447.4

0.065

317.5

0.040

390.4

0.055

451.8

0.065

GI-46

30.2

0.010

43.2

0.010

80.3

0.020

110.0

0.030

210.3

0.060

154.5

0.040

186.1

0.050

212.2

0.060

GI-50

53.2

0.010

75.6

0.020

139.9

0.040

191.3

0.050

381.9

0.110

272.7

0.070

334.3

0.090

385.6

0.110

GI-76

13.1

0.010

50.7

0.010

94.5

0.020

129.6

0.030

248.2

0.070

182.2

0.050

219.5

0.060

250.4

0.070

GI-80

46.4

0.010

66.7

0.020

124.6

0.030

171.1

0.050

343.6

0.100

244.6

0.060

300.4

0.080

346.9

0.100

GI-36

19.8

0.010

28.1

0.010

69.0

0.020

70.9

0.020

135.3

0.040

99.5

0.030

119.7

0.030

136.6

0.040

GI-38

35.7

0.010

50.8

0.010

94.2

0.030

128.9

0.040

246.2

0.070

180.9

0.050

217.8

0.060

248.4

0.070

GI-41

83.5

0.010

119.9

0.020

223.9

0.030

307.2

0.040

588.5

0.080

432.1

0.060

433.0

0.065

593.9

0.085

HW-71

46.4

0.010

61.8

0.020

113.8

0.030

155.5

0.040

296.2

0.080

217.9

0.060

262.1

0.070

299.0

0.080

GI-62

43.2

0.010

61.6

0.020

114.2

0.030

156.2

0.040

298.4

0.080

219.3

0.060

264.0

0.070

301.2

0.080

GI-64

53.3

0.010

77.2

0.020

145.6

0.040

200.4

0.050

385.4

0.110

282.5

0.080

340.7

0.090

388.9

0.110

GI-67

54.0

0.010

76.7

0.020

141.4

0.040

193.2

0.050

368.3

0.100

270.9

0.070

326.0

0.090

371.6

0.100

GI-69

45.0

0.010

62.3

0.020

111.8

0.030

151.4

0.040

285.3

0.080

210.8

0.060

252.9

0.070

287.9

0.080

CHW-82

115.3

0.010

164.3

0.013

304.7

0.023

417.1

0.037

835.7

0.077

595.1

0.053

730.7

0.063

843.8

0.077

EXT

SW-X5

29.0

0.003

46.6

0.003

81.4

0.005

112.3

0.008

218.3

0.015

158.9

0.010

191.8

0.015

220.8

0.015

1:½

yr R

IT

ota

l R

un

off

Pea

k R

un

off

1:10

yr R

I1:

20yr

RI

To

tal

Ru

no

ffP

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Ru

no

ffT

ota

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un

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Pea

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off

Pea

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un

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Pea

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Su

b-

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t

1:1y

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I1:

2yr

RI

1:5y

r R

I1:

50yr

RI

TA

BL

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c: P

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ST

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MW

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16

5.3 MINOR SYSTEM In order to satisfy the City of Cape Town policy for the Management of Urban Stormwater Impacts (COCT, 2009), the proposed stormwater system for the De Zicht development achieves the following: The underground stormwater system is designed to accommodate the more

frequent storms up to 1:5 year RI. The developed site runoff is conveyed along internal roads and parking

channels and is discharged in catchpits.

The stormwater captured is routed via underground pipes to new stormwater ponds constructed in available open spaces.

Runoff quality management controls are provided in the form of:

- Stormwater ponds - Enhanced swales - Bio-retention areas

(Refer to Diagram ‘5d’: Typical Stormwater pond on page 19,

Diagram ‘5e’: Typical Enhanced swale on page 20, Diagram ‘5f’: Typical Bio-retention area on page 21)

Refer to Diagram 5a on page 13 for proposed positions of runoff quality management controls.

The above-mentioned controls (performance based application) is sized to reduce pollutant loads in a 1:½ year RI to the following:

- 80% of Suspended Solids (SS), - 45% of Total Phosphorus (TP).

(Refer to Table ‘5c’: Water Quality Volume Treatment on page 18) Proposed catchpits is also constructed to function as sediment traps for the

accumulation and removal of sediments and litter.

The treatment of post-development runoff for a 1:½ year RI storm is provided within a treatment train diagram. The treatment performance of the controls provided is detailed in Table ‘5c’ on page 18

17

5.4 MAJOR SYSTEM The road network is utilised for the drainage of excess runoff not entering the

underground system.

The development of De Zicht allows for overland stormwater to be channelled along the internal road network and discharges into the provided stormwater management facility such as ponds and bio-retention areas.

The road network makes allowance for stormwater runoff in excess of 1:5

year RI.

The bio-retention areas and stormwater ponds are designed to manage the developed site’s runoff and discharge the pre-development flows to existing stormwater systems.

The anticipated discharge from these bio-retention areas and stormwater ponds during various RI storms is provided.

(Refer to Table ‘5g’: Proposed Bio-retention and Stormwater pond Modelling Results on page 22)

Based on discussions held with City officials from Catchment Management &

District Roads & Stormwater, further investigation will be undertaken to clarify outfalls from existing stormwater systems to the existing receiving water body (Diep River). This information will be presented at detail design stage to inform the City of bulk stormwater routing and outfall capacities.

(Refer to Diagram ‘5h’: Existing Bulk Stormwater Outfall Route on page 23)

Upstream stormwater flowing along Sylvia Street and Warren Way is to be

redirected into a new stormwater pipe system that discharges into the Blaauwberg Road reserve and managed in future as part of the Blaauwberg Road Extension construction. Refer to Diagram 5a on page 13 for proposed external stormwater routing.

The overland stormwater will be forced along Warren Way’s kerbs and channels and discharge into a bulk inlet to Blaauwberg Road reserve. The outfall pipe has been sized to accommodate up to 1:100 year RI runoff.

All Additional Data requested by Catchment & Stormwater Management will be presented as an addendum to this report.

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29.0

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GI-

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GI-

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0.3

81

0.2

93

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76.0

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GI-

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116.0

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22.0

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173.0

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GI-

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GI-

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19.0

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-173.0

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192.0

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GI-

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GI-

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70

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36.0

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36.0

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GI-

76

GI-

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36.0

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83.0

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GI-

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83.0

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137.0

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GI-

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203.0

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-31.0

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0.0

17

26.0

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--

26.0

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PIP

E-

0.2

87

0.2

17

3.0

00

153.0

00

510.0

00

12.0

00

HW

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56.0

00

140.0

00

44.0

00

98.0

00

153.0

00

GI-

67

GI-

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m³

m³

m³

m³

m³

GI-

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151.0

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192.0

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PIP

E-

-36.0

00

-G

I-80

GI-

50

PIP

E-

-83.0

00

-G

I-50

-137.0

00

-G

I-34

-203.0

00

-H

W-3

5

--

31.0

00

-H

W-3

5

PO

ND

'1'

SW

PO

ND

-26.0

00

-H

W-3

5

-510.0

00

--

-

GI-

41

HW

-71

PIP

E-

-140.0

00

-H

W-7

1

98.0

00

GI-

64

GI-

67

PIP

E-

-98.0

00

-G

I-67

PIP

E-

-153.0

00

-G

I-69

GI-

2

GI-

5

GI-

7

GI-

8

GI-

10

GI-

11

GI-

76

GI-

34

GI-

29

HW

-35

0.4

09

0.2

91

47.0

00

-G

I-80

0.7

03

0.5

21

84.0

00

-G

I-41

-

GI-

34

GI-

29

PIP

E

PIP

E

GI-

50

GI-

46

HW

-35

GI-

34

0.4

48

0.3

43

54.0

00

-G

I-64

0.3

55

PIP

E-

-20.0

00

-G

I-38

GI-

36

0.4

57

0.3

25

55.0

00

-G

I-67

PIP

E-

-56.0

00

-G

I-41

0.2

09

PIP

E-

-44.0

00

-G

I-64

0.2

00

0.1

53

24.0

00

-192.0

00

216.0

00

GI-

13

0.4

49

54.0

00

-G

I-50

0.3

22

0.2

54

31.0

00

-G

I-46

0.1

88

0.7

60

0.5

14

20.0

00

--

20.0

00

GI-

36

GI-

38

GI-

38

36.0

00

-20.0

00

56.0

00

GI-

38

GI-

41

0.2

36

0.1

61

--

44.0

00

GI-

62

GI-

64

HW

-35

PIP

E-

-216.0

00

-H

W-3

5G

I-13

0.3

57

0.2

11

34.0

00

--

34.0

00

GI-

20

GI-

5P

IPE

--

34.0

00

-H

W-3

5G

I-20

0.5

31

0.2

61

-116.0

00

HW

-82

BIO

-RE

T. A

RE

AE

-SW

AL

E88.0

00

59.4

00

56.6

00

-B

IO-R

ET

. A

RE

A1.0

04

0.7

03

116.0

00

-H

W-8

2

PIP

E-

-198.0

00

-H

W-7

1G

I-69

SW

PO

ND

-382.0

00

--

-

BIO

-RE

T. A

RE

A360.0

00

355.7

00

-299.1

00

--

0.5

12

0.2

48

45.0

00

-153.0

00

198.0

00

GI-

69

HW

-71

HW

-71

44.0

00

115.0

00

338.0

00

382.0

00

HW

-71

PO

ND

'2'

-56.6

00

56.6

00

E-S

WA

LE

BIO

-RE

T. A

RE

A

0.4

09

0.2

64

44.0

00

GI-

62




DIAGRAM 5d

NOT TO SCALE

(PLAN & PROFILE SHOWN)

NOTES:

ALL DATA REFER TO INFORMATION SOURCED FROM THEFOLLOWING DOCUMENT

GEORGIA STORMWATER MANAGEMENT MANUALVOLUME 2: TECHNICAL HANDBOOK -FIRST EDITION (AUG 2001)

TYPICAL STORMWATER POND

TYPICALSTORMWATER POND

(MICROPOOL DETENTION)




DIAGRAM 5e

NOT TO SCALE


NOTES:



TYPICAL ENHANCED SWALE

TYPICALENHANCED SWALE




DIAGRAM 5f

NOT TO SCALE


NOTES:



TYPICAL BIO-RETENTION AREA

TYPICALBIO-RETENTION

AREA

1:2

1:5

1:10

1:20

1:50

1:10

01:

21:

51:

101:

201:

501:

100

1:2

1:5

1:10

1:20

1:5

01:

100

m³/

sm

³/s

m³/

sm

³/s

m³/

sm

³/s

m³/

sm

³/s

m³/

sm

³/s

m³/

sm

³/s

mm²

m³

mm

mm

³/s

m³/

sm

³/s

m³/

sm

³/s

m³/

s

1.000

0.16

-

0.900

0.10

0.10

0.000

0.05

-

1.900

0.20

0.20

0.027

0.258

0.025

0.027

0.041

0.068

0.005

0.005

0.006

0.010

1.200

0.30

1.20

0.084

0.187

0.227

0.049

0.062

0.102

0.186

2.700

1426

675

334

0.007

0.018

0.032

0.056

0.080

0.102

0.604

0.124

0.146

Bio-Ret

1.500

355

0.004

0.050

Pea

k F

low

Pea

k F

low

Pea

k F

low

AT

TE

NU

AT

ED

OU

TF

LO

W

Pea

k F

low

0.104

0.345

0.413

0.481

0.573

0.429

BIO-RET & POND

Pea

k F

low

Pea

k F

low

Pea

k F

low

Pea

k F

low

1.950

0.30

0.50

1625

AT

TE

NU

AT

ION

0.407

Pea

k F

low

OU

TL

ET

Pro

po

sed

Po

nd

O

utl

et S

izes

OF

F

SE

TH

WA

RE

A

955

0.675

0.753

Pro

po

sed

Po

nd

D

imen

sio

ns

Pond-1

0.027

0.066

0.117

0.259

Pea

k F

low

2.500

Pea

k F

low

Pea

k F

low

Pea

k F

low

VO

LP

eak

Flo

wP

eak

Flo

wP

eak

Flo

w

0.507

0.626

0.042

0.021

0.004

PR

E-D

EV

EL

OP

ME

NT

INF

LO

W

Dyn

amic

Wav

e F

low

Res

ult

s

Pea

k F

low - -

0.252

0.073D

ynam

ic W

ave

Flo

w R

esu

lts

Dyn

amic

Wav

e F

low

Res

ult

s

TA

BL

E 5

g:

PR

OP

OS

ED

BIO

-RE

TE

NT

ION

& S

TO

RM

WA

TE

R P

ON

D M

OD

EL

LIN

G R

ES

UL

TS

-

Pond-2

--

D

PO

ST

-DE

VE

LO

PM

EN

T IN

FL

OW

Pea

k F

low

0.322

DUNOON

KILLARNEY GARDENS

RICHWOOD

KILLARNEYRACE TRACKS

ATLASPARK

THE SITE

N7 (

NA

TIO

NA

L R

OA

D)

PO

TSD

AM

RO

AD

PO

TS

DA

M R

OA

D

TYG

ER

BER

G V

ALL

EY R

OA

D

N7 (

NA

TIO

NA

L R

OA

D)

PARKLANDS

TABLE VIEW

MALIBO

NGW

E DRIVE

RA

ILW

AY

LIN

E

RA

ILW

AY

LIN

E

RA

ILW

AY

LIN

E

DIEP R

IVER

DIE

P R

IVE

R

KLEIN STINK RIVER

CO

NT

ER

MA

NS

KL

OO

F R

OA

D

DIAGRAM 5h

SCALE 1:10 000



CESA


ATLANTICHILLS

DE ZICHTEXISTING BULK

STORMWATER OUTFALL ROUTE

RACINGPARK

ø750

INLET FROMDE ZICHT

INLET FROMFUTURE DEV.

OUTLETOF POND

3x ø525mm(N7 CROSSING)

ø450

ø52

5

ø52

5ø525

ø825

ø82

5

ø900

ø1050

ø1050

ø1050

ø1200

ø1200

ø1350

EXISTINGOUTFALLDRAIN

LINK BETWEEN N7 CROSSINGAND ø375mm TO BE CONFIRMED

ø375

ø375

24

6 PROPOSED SEWER The internal sewer reticulation is provided: To optimum pipe gradients to ensure a self-cleansing system and reduce the

maintenance on the system. To be water tight through using precast sewer manholes with pre-

manufactured pipe connections to inverts to reduce stormwater ingress into the system.

To accommodate peak sewer flows.

6.1 ASSUMPTIONS FOR SEWER MODELLING The internal sewer is modelled on the following assumptions: The minimum design standards of the City of Cape Town is maintained

The Harmon Peak Factor method is used for design flow calculations The maximum pipe capacity equals 80% of the full bore flow

A minimum velocity of 0.7 m/s is achieved

Each unit contributes the following:

- 360 l/unit/day for 1 bed units (No of calculated 73 x 8 = 584) - 480 l/unit/day for 2 bed units (No of calculated 73 x 2 = 146) - 720 l/unit/day for 3 bed units (No of calculated 73 x 2 = 146)

(Assuming 80% of water usage as per COCT Water Tariff Policy)

3 contributors per dwelling unit.

876 dwelling units for the completed site development.

6.2 SEWER MODELLING RESULTS The sewer calculation results are as follows: AADF = 385 440 l/d Estimated population = 2628 Harmon Peak factor = 3.491 PWWF = 15.574 l/s

Refer to Diagram 6 on page 25 for the positions of the development’s sewer reticulation.

BE

RG

ZIC

HT

RO

AD

MORRIS SHELL DRIVE

UITZICH

BE

RG

ZIC

HT

RO

AD

ANNANDALE DRIVE

MORRIS SHELL DRIVE

CO

CK

LE

CL

OS

E

LIMPET CRESCENT

LIM

PE

T S

TR

EE

T

LIMPET CLOSE

LIMPET STREET

CH

ITT

EN

WA

Y

OY

ST

ER

ST

RE

ET

AB

AL

ON

E S

TR

EE

T

FU

TU

RE

CA

RM

INE

DR

IVE

EX

T.

WA

RR

EN

WA

Y


SYLVIA STREET

JETTA SHELL WAY

2

45

6

7

8

9

11

1

LPGAS

REFUSEYARD

ENTRANCE

CL

UB

HO

US

E

SO

CC

ER

42 43

70

71

72 73

46

44

41POOL

262523 24

32

5759 58

69

67

68

272831 30 29

45

48 475051 495253

55

56

54

22

21

3

19

20

3433

3738394036

35

16

13

14

10

18

17

12

15

606164 63 6265

66

1:3

0.2

RE

TA

IN E

X. ø

200m

m F

S

ø350m

m F

S

ø450mm BULK WM

ø450mm BULK WM


FOREBAY

FOREBAY

PERMANENT POOLAQUATICBENCH

EX

. ø450m

m B

UL

K W

M

V

V

V

V

AV


EX

. ø

350m

m S

EW

ER

RM


EX

. ø400

mm

BU

LK

WM

EX. ø200mm WM

EX

. ø160m

m W

M

EX

. ø110m

m W

M

NEW ø160mm PIPEFOR FUTURE USE

BM

H V

H

H

H

H

V

V

V

V

V

V

V

V

V

V

FUTURE ø160mm PIPEFOR DEVELOPMENTOF ADJACENT PROPERTY

SEWER OUTFALL TO EXISTINGPUMP STATION TO FORM PARTOF DEVELOPMENT OF ANNANDALE FARM

INITIAL BULK METERTO BE RELOCATEDTO MAIN ENTRANCE

UPGRADE BULK SUPPLYTO ø200mm PIPE & REMOVEPREVIOUS FEEDS

VH

H

SV

V

V

AV

V

V

V

V

V Hø160 F

S

ø160 F

S

ø160 FS

ø160 F

S

ø160 FSø160 FS

ø160 FS

ø160 FS

ø160 FS

ø160 F

S (F

UTU

RE

)

ø160 FS

ø160 F

S

ø160 F

S

ø160 F

S

ø160 FS

ø110 WM

ø1

10m

m - C

L 1

2

ø110 W

M

ø110 W

M

ø110 W

M

ø160

ø110 WM

ø110 W

M

ø110 W

M

ø110 W

M

ø110 WM

ø160 W

M

ø160 WM

ø110 WM

ø110 WM

ø110 WM

ø110 WMø110 WM

ø110 WM

H

HH

HH

H

H

H

H

H

H

H

H

H

B

HH

H

H

H

H

V

VV

V

VV

V

V

V

V

V

V

V

V

V

V

V

H

H

H

HH

V

V

ø110 W

M

ø110 W

M

V

BM

V

V

RE

FU

SE

PA

RK

ING

ø200ø110

SCALE 1:1500

DIAGRAM 6DE ZICHT

SEWER & WATERSERVICES PLAN




CESAMV HB

EXISTING STORMWATER

EXISTING SEWER

NEW SEWER

EXISTING POTABLEWATER

NEW POTABLE WATER, BOOSTER,VALVES, METERS & HYDRANTS

NEW STORMWATER

LEGEND (PLAN):

26

6.3 SEWER PROPOSAL Based on the results of the Sewer Model the following recommendations are made: Portions of the existing sewer reticulation pipework will be retained for the

service provision of the development.

New ø160mm & ø200mm sewer pipes will be installed and tie-in to existing pipe work.

The private sewer reticulation will tie-in to the existing ø200mm sewer outfall

and discharge into the existing sewer pump station currently switch off (no incoming sewerage).

Based on discussions held with City officials from District Water & Sanitation,

the existing sewer pump station will be recommissioned when required. The electrical supply to the pump station will be reconnected to an Eskom

supply point and is to be metered for the City’s account. It was agreed with City officials that the existing sewer service connections,

located upstream of the site, will not be accommodated within the site’s proposed reticulation.

Future sewer routes for the upstream property will form part of the Annandale

farm development. Refer to Diagram 6 on page 25 for future sewer route proposal for the upstream property.

27

7 WATER The internal water reticulation is provided to achieve the required fire flow conditions as guided by the “Guidelines for Provision of Engineering Services and Amenities in Residential Developments” as published by the CSIR.

7.1 ASSUMPTIONS FOR WATER MODELLING The proposed water reticulation will be designed to accommodate the following: Domestic Water Demand Fire Water Demand

7.1.1 DOMESTIC WATER DEMAND

The proposed water model (domestic) is designed on:

A maximum water head of 90m (under zero flow conditions)

A minimum water head of 38m (under instantaneous peak demand)

(based on pipe depth of 1.2m, building height of 12m and working pressure of 24m)

An Average Annual Water Demand (AAWD) for the following:

- 450 l/unit/day for 1 bed units (No of calculated 73 x 8 = 584) - 600 l/unit/day for 2 bed units (No of calculated 73 x 2 = 146) - 900 l/unit/day for 3 bed units (No of calculated 73 x 2 = 146)

(Assuming that the residential area demands between 450 – 900 l/unit/day)

Pipe sizes of ø110mm and ø160mm

876 dwelling units on completed site development. 7.1.2 FIRE WATER DEMAND

At detail design stage the water reticulation for the development will be reviewed to confirm the service for fire flow conditions. The following fire flow conditions will be evaluated: Fire Risk Category = low to moderate

(Based on discussions with fire protection consultants) Minimum fire flow demand = 6000 l/min

Fire flow duration = 4 hrs

Maximum hydrant spacing = 180m

Minimum hydrant flow rate = 1500 l/min (25l/s) with residual head of 15m

A fire condition with hydrants in a 270m radius discharging simultaneously.

28

7.2 WATER MODELLING RESULTS The domestic water calculation results are as follows: AADD = 481 800 l/d Number of Equivalent Erven (ee) = 481

(Based on equivalent erven equating 1000 l/day) Instantaneous PF = 6.10 (based on the ee) Peak Domestic Water Demand = 34.02 l/s (instantaneous flow) Optimum Water Velocity = 0.6 to 1.2 m/s

7.3 WATER PROPOSAL Based on the results of the Water Model the following recommendations are made: One municipal connection is to be made into the development The existing ø450mm bulk water main traversing the site is to be relocated

along the future road reserve of Carmine Drive and Blaauwberg Road Extension.

The existing water reticulation will be altered to provide a water connection

point at the site’s main entrance gate. Based on discussions held with City officials from District Water & Sanitation,

the existing ø400mm ductile iron bulk watermain is to be provided with a pressure reducing valve, if required. This will be clarified at detail design stage.

The existing ø160mm water mains currently connected to Richwood development is to be end capped (removed).

Pipe sizes range from ø110mm to ø160mm will supply the development.

Refer to Diagram 6 on page 25 for the position of the development’s water reticulation.

29

8 ROADS, ACCESS AND PARKING The road hierarchy and access to the development was based on the recommendations covered in the Traffic Impact Assessment prepared by HHO Infrastructure Engineers.

8.1 ACCESS

Access to the De Zicht development is confirmed to be formalised off the existing bellmouth located at the intersection of Sylvia Street and Warren Way along the eastern boundary of the site.

(Refer to Diagram ‘8a’: Road Access Plan on page 31) Two additional access gates will be provided along Warren Way for emergency vehicles or delivery truck movement. A turning circle is proposed at the end of Warren Way and is adequately sized to accommodate the turning movement of refuse and delivery trucks.

(Refer to Diagram ‘8b’: Turning Circle Plan on page 32)

8.2 INTERNAL NETWORK The geometric design, cross section and structural design of the roads are based on accepted standards for the class of road proposed. All road surfacing shall be brick paving in order to compliment the aesthetics and landscaping. The road layer works will be finalised during the detail design stage of the project.

9 TELECOMMUNICATION The installation of cable sleeves and draw boxes will form part of the Civil Engineering services. The installation of all telecommunication sleeves will be in accordance with the requirements of SABS 1200 LC.

10 ELECTRICAL

Electrical services will be provided in accordance with the electrical services report compiled by Gibb Consulting Engineers. The installation of electrical sleeves will be covered with the detail design of the development and electrical sleeves will form part of the construction of the civil engineering services. The installation of electrical sleeves will be done in accordance with the construction standards specified within SABS 1200 LC.

30

11 SOLID WASTE MANAGEMENT

De Zicht – Milnerton, Cape Town being a private development, will provide a suitable refuse area for the collection of solid waste generated in the development. This refuse area will be constructed along the eastern boundary of the site and provide access in accordance with the municipal requirements along Warren Way.

MORRIS SHELL DRIVE

UITZICHT CRESCENTB

ER

GZIC

HT

RO

AD

UIT

ZIC

HT

CR

ES

CE

NT

CARMINE DRIVE

TY

GE

RB

ER

G V

AL

LE

Y R

OA

D

FUTURE CARMINE DRIVE EXT.

WARREN WAY

FUTU

RE B

LAAU

WBERG

RO

AD E

XT.

SYLVIA S

TREET

JETTA SHELL WAY

ELECTRICAL SERVITUDE




DE ZICHTROAD ACCESS PLAN

DIAGRAM 8a

SCALE 1:1500

RICHWOOD

DE ZICHTDEVELOPMENT

PROPOSEDWARREN WAYROAD RESERVE

TURNING CIRCLEFOR CUL-DE-SAC& REFUSE REMOVAL

POSITION OFGATEHOUSETO DEZICHT

SE

RV

ICE

SE

RV

ITU

DE

RO

AD

RE

SE

RV

E

R=9.5

R=11

ADJACENTDEVELOPMENT

WA

RR

EN

WA

Y

EX

ISTIN

G C

AD

AS

TR

AL




DE ZICHTTURNING CIRCLE PLAN

DIAGRAM 8b

SCALE 1:200

DE ZICHTDEVELOPMENT

PR

OP

OS

ED

CA

DA

ST

RA

L

34

III LIST OF REFERENCES

AMEC Earth and Environmental, Centre for Watershed Protection, Debo and Associates, Jordan Jones and Goulding & Atlanta Regional Commission, 2001a. Georgia Stormwater Management Manual – Vol.1: Stormwater Policy Guidebook. Prepared for Atlanta Regional Commission, August 2001

AMEC Earth and Environmental, Centre for Watershed Protection, Debo and Associates, Jordan Jones and Goulding & Atlanta Regional Commission, 2001b. Georgia Stormwater Management Manual – Vol.2: Technical Handbook. Prepared for Atlanta Regional Commission, August 2001

Aurecon Consulting Engineers, 2010. Stormwater Management Plan – Annandale Ridge

Phase 1. Prepared for Pact Developers, November 2010 City of Cape Town, 2009a. Management of Urban Stormwater Impacts Policy –

Version 1.1. Prepared for Catchment, Stormwater and River Management Branch, City of Cape Town: Transport Roads & Stormwater Directorate, May 2009.

City of Cape Town, 2009b. Floodplain and River Corridor Management Policy – Version 2.1. Prepared for Catchment, Stormwater and River Management Branch, City of Cape Town: Transport Roads & Stormwater Directorate, May 2009.

Core Geotechnical Consultants, 2017. Annandale Farm: De Zicht Erf 36555 – Geotechnical

Investigation. Prepared for Balwin Properties (Pty) Ltd, Aprilr 2017

CSIR Building and Construction Technology, 2000. Guidelines for Human Settlement Planning and Design. Prepared for The Department of Housing, Republic of South Africa.

Rawls, W.J., Brakensiek, D.L. and Miller, N. 1983. Green-Ampt Infiltration Parameters for

Soils Data. Prepared for Journal of Hydraulic Engineering, American Society of Civil Engineers, January 1983.

Schulze, R.E., Schmidt, E.J. and Smithers, J.C. 2004. Visual SCS-SA: User Manual – Version 1. Prepared for School of Bio-resource Engineering & Environmental Hydrology, University of Kwazulu Natal, September 2004.

Soil Conservation Service, 1986. Urban Hydrology for Small Watersheds. Technical Release 55, U.S. Department of Agriculture, Washington, DC. US Environmental Protection Agency, 2004. Stormwater Management Model (SWMM): User

Manual – Version 2. Prepared for Water Supply & Water Resources Divisions, US Environmental Protection Agency, November 2004.

PRELIMINARY CIVIL ENGINEERING SERVICES REPORT Zicht/Draft Amen… · preliminary civil engineering services report for the provision of roads and civil engineering services for de

Documents