SYABAS GUIDELINES ON PLANNING AND DESIGN FOR
WATER SUPPLY SYSTEM
Table of Contents FOREWORD ABBREVIATIONS 1.0 GENERAL 1.1 Scope 1.2 Definitions
1.3 Standards and Specifications
1.4 Interpretation of Guidelines
2.0 PLANNING FOR WATER SUPPLY
2.1 General
2.2 Development Proposals 2.2.1 General
2.2.2 Reservoirs and Tanks
2.2.3 Site Dimensions for Reservoirs and Tanks
3.0 EXTERNAL WATER SUPPLY SYSTEM
3.1 Application for Source of Water Supply 3.2 Concept Design Submissions
3.3 Detailed Design Submissions 3.3.1 Civil Works
3.3.2 Mechanical and Electrical Works 3.3.3 Geotechnical Works
3.4 Design Guidelines 3.4.1 Water Pipes
a. Hydraulic Requirements
b. Pipe Laying Requirements c. Valves and Utilities
3.4.2 Reservoirs and Tanks
a. Storage Capacity b. Hydraulic Requirements c. Boundary Setback d. Materials and Measures
e. Pipeworks Inside Reservoirs and Tanks f. Control Valves g. Pipe Strainers h. Miscellaneous 3.4.3 Pumping Stations a. General b. Pump Plinths 3.4.4 Geotechnical Considerations
a. Reservoir, Tank and Pumping Station Buffer Zones for Slopes b. Slope Stability Analysis
c. Drainage Provisions d. Slope Surface Protection
e. Reservoir, Tank and Pumping Station Foundation 3.6 Materials
3.7 Checklist
4.0 INTERNAL PLUMBING SYSTEM
4.1 Plans
4.2 Technical Requirements 4.2.1 General
4.2.2 Pipes and Valves
4.2.3 Water Tanks within Consumer Premises
a. Capacity
b. Pipeworks and Materials c. Safety and Security
4.2.4 Pumping Systems 4.2.5 Hot Water Systems 4.2.6 Swimming Pools
4.3 Water Conservation
4.3.2 Water Conservation Measures 4.4 Checklist 5.0 METERING 5.1 General 5.2 Locations of Meters 5.3 Sizes of Meters
5.4 Automatic Meter Reading System (AMR)
5.5 Meter stands
5.5.1 General
5.5.2 Markings for Meter stands
6.0 ELECTRICAL SYSTEM
6.1 Standards, Code of Practice, Rules and Regulations
6.2 Detailed Design Submissions
6.3 Power Supply Requirements 6.4 HT Installations
6.5 LV Installations
6.6 Essential Power Supply
6.7 Motor Starter Panels
6.8 Electric Motors
6.9 Internal Lighting and Power 6.10 External Lighting Installations
6.11 Lighting and Surge Protection Systems 6.12 Earthing Systems
6.13 Electrical Spare Parts
6.14 Electrical As-Built Fitted Drawings 6.15 Testing and Commissioning
6.16 Variable Speed Drive (VSD) Pumping System 6.17 Checklist
7.0 MECHANICAL SYSTEM
7.1 General
7.2 Detailed Design Submissions
7.2.1 First Stage (Design Stage before Tender Award)
7.2.2 Second Stage (After Tender Award during Approval Stage of Equipment) 7.3 Planned Water Quantity and Number of Pump Units
7.4 Pumpsets
7.4.1 Duties and Selection
7.4.2 Horizontal Split Casing Pumps 7.4.3 End Suction Pumps
7.4.4 Pump Casing, Rotating Element, Driving Coupling, Gland Sealing and Other Pump Accessories
7.5 Pressure Gauges
7.6 Suction and Delivery Pipes 7.7 Pipeworks
7.8 Valves
7.8.1 Sluice Valves 7.8.2 Butterfly Valves
7.8.3 Non-slam Type Check Valves and Surge Calculation 7.8.4 Altitude Valves
7.9 Surge Suppression Systems 7.10 Mechanical Handling Equipment 7.11 Mechanical Spare Parts
7.12 Variable Speed Drive (VSD) Pumping System 7.13 Checklist
8.0 SCADA/ TELEMETRY SYSTEM
8.1 General
8.2 Hardware Requirements 8.2.1 General
8.2.2 Outstations
8.2.3 Remote Terminal Units 8.2.4 GPRS/ GSM Modem 8.2.5 Video Cameras
8.3 Communication Systems
8.4 Operation Requirements on SCADA System
8.4.1 Introduction
8.4.2 Suction Reservoirs and Suction Tanks 8.4.3 Pumping stations
8.4.4 Reservoirs and Tanks
8.4.5 Telemetry Systems for Gravity Fed Reservoirs and Tanks 8.5 Spare Parts
8.6 Checklist
9.0 CAPITAL COST CONTRIBUTION (SKP)
9.1 Definitions 9.2 Charge Rates
9.3 Exemption from Capital Cost Contribution 9.4 Effective Date
10.0 SERVICE CHARGES
10.1 Charges for Connection to Public Mains 10.2 Charges for Disconnection and Reconnection 10.3 Charges for Meter Tests
10.4 Charges for Swimming Bath Tests 10.5 Charges for Licenses to Carry Out Work 10.6 Charges for Pressure Test on Mains 10.7 Agency Fees
10.8 Charges for New Installation without Tapping or Tee-Connection 10.9 Supervision Charges for Connection
APPENDICES
A Standard Forms
B Standard Drawings
C Design Checklists
FOREWORD
Syarikat Bekalan Air Selangor Sdn. Bhd. (SYABAS) is responsible for the water supply services in the State of Selangor and the Federal Territories of Kuala Lumpur and Putrajaya. Qualified consulting engineers, planners and architects or other agents of the Developers are required to submit their design proposals for water supply works to SYABAS in order to ensure that the water supply systems meet the planning, design, operation and maintenance requirements of SYABAS.
This document is a statement of general policies and design standards expected of new water supply works for external water supply system as well as internal plumbing system in the State of Selangor and the Federal Territories of Kuala Lumpur and Putrajaya.
The document has been adapted and revised from the document “GARIS PANDUAN PENGEMUKAAN – Sistem Bekalan Air Di Negeri Selangor, Wilayah Persekutuan Kuala Lumpur dan Putrajaya”, which was previously published by Perbadanan Urus Air Selangor Berhad (PUAS).
The standards and parameters set out in this document may be subject to revision. Nothing herein shall be construed as relieving the responsibilities of any person or entity responsible for the design, execution and completion of the works. The consulting engineers, planners and architects shall be expected to exercise professional judgement and sound engineering practices in developing the design proposals.
ABBREVIATIONS
NAMESANSI - American National Standards Institute
ASME - American Society of Mechanical Engineers
BOMBA - Jabatan Bomba dan Penyelamat (Fire and Rescue Department)
BSI - British Standards Institution
DCA - Department of Civil Aviation
DOE - Department of Environment
DOSH - Department of Occupancy Safety and Health of Malaysia
EN - European Committee of Standardization
IEC - International Electrotechnical Commission
IEEE - Institute of Electrical and Electronics Engineers
IES - Illuminating Engineering Society
ISO - International Organization for Standardization
JKAS - Jabatan Kawalselia Air Selangor
JKR - Jabatan Kerja Raya
MASMA - Manual Saliran Mesra Alam Malaysia
MWA - Malaysian Water Association
PUAS - Perbadanan Urus Air Selangor Berhad
SIRIM - Standards and Industrial Research Institution of Malaysia
ST - Energy Commission (Suruhanjaya Tenaga)
SYABAS - Syarikat Bekalan Air Selangor Sdn. Bhd.
TM - Telekom Malaysia Berhad
TNB - Tenaga Nasional Berhad
TERMS
ABS - Acrylonitrile Butadiene Styrene
ACB - Air Circuit Breaker
AMR - Automatic Meter Reading
ARI - Average Recurrence Interval
AutoCAD - Automation Computer Aided Design
BS - British Standard
BWL - Bottom Water Level
CD - Compact Disc
CEMEP-EU - European Committee of Manufacturers of Electrical Machines and Power Electronics and European Commission
CT - Current Transformer
DB - Distribution Board
Dia. - Diameter
DMZ - District Meter Zone
DOL - Direct On-line
Elev. - Elevation
ELR - Earth Leakage Relay
etc - et cetera
FRP - Fibre Reinforced Polyester
FS - Factor of Safety
fsd - Full-scale Deflection
G.I. - Galvanised Iron
GPRS - General Packet Radio Service
GRP - Glass Reinforced Plastic
GSM - Global System for Mobile Communications
HDPE - High Density Polyethylene
HGL - Hydraulic Grade Line
HL - Head Loss
HSL - Highest Supply Level
HT - High Tension
HWC - Hazen-William Coefficient
ID - Internal Diameter
IDMT - Inverse Definite Minimum Time
IP - Ingress Protection
LED - Light Emitting Diode
LPU - Lightning Protection Unit
LV - Low Voltage
M&E - Mechanical and Electrical
MCB - Miniature Circuit breaker
MCCB - Moulded Case Circuit Breaker
MMI - Man-Machine Interface
MS - Malaysian Standards
NPSH - Net Positive Suction Head
NRW - Non Revenue Water
O&M - Operation and Maintenance
ODL - Ordnance Datum Level
p.a - Per annum
PC - Personal Computer
PE - Polyethylene
PID - Proportional, Integral, Derivative
PKNS - Perbadanan Kemajuan Negeri Selangor
PLC - Programmable Logic Controller
PN (16) - Pressure Number of 16 bars
POB - Polyolefine Blend
PP-R - Polypropylene Random Copolymer
PT - Power Transformer
PTFE - Polyetrafluoroethylene
RBE - Report-by-exception
RC - Reinforced Concrete
RCD - Residual Current Device
RL - Reduced level
RTU - Remote Terminal Unit
SCADA - Supervisory Control and Data Acquisition
Sdn. Bhd. - Sendirian Berhad
SKP - Sumbangan Kos Pembangunan (Capital Cost Contribution
SMS - Short Message Service
SPT - Standard Penetration Test
SWA - Steel Wire Armoured
SWG - Standard Wire Gauge
TEFC - Totally Enclosed, Fan Cooled
TWL - Top Water Level
uPVC - Unplasticised Polyvinyl Chloride
v:h - Vertical Height : Horizontal Length
VSD - Variable Speed Drive
WC - Water Closet
WTP - Water Treatment Plant
XLPE - Crosslinked Polyethylene
UNITS
% - Percent
A - Ampere
d - Day
deg. C - degree Celsius
deg. F - degree Fahrenheit
ft2 - Square Foot ha - Hectare hr - Hour kA - Kilo Ampere kg - Kilogram km - Kilometre kW - Kilowatt
l/d - Litre per day
l/s - Litre per second
lcd - Litre per capita per day
m - Metre
m/s - Metre per second
m3 - Cubic Metre
m3/hr - Cubic Metre per hour
m3/month - Cubic Metre per month
mg/l - Milligram per litre
Ml - Million Litres
Mld, Ml/d - Million Litres per day
mm - Millimetre
mm2 - Square Millimetre
Mohm - Mega Ohm
No. - Number
rpm - Revolution per minute
V - Volt
Var - Volt-ampere reactive
W - Watt
1.0 GENERAL
1.1 SCOPE
These guidelines deal with the planning and design for water supply systems in the State of Selangor and the Federal Territories of Kuala Lumpur and Putrajaya. It covers external water supply systems as well as internal plumbing systems for individual premises. It does not cover all aspects of water supplies for fire fighting.
The guidelines are prepared to provide guidance to engineers, architects, developers, contractors and licensed plumbers, and should be of interest also to water consumers.
1.2 DEFINITIONS
For the purpose of these guidelines unless the context otherwise requires, the following definitions shall apply:-
a. Approved Standard
Standard or specification or code of practice issued by Standards and Industrial Research Institution of Malaysia (SIRIM) or if such is non-existent, by the British Standards Institution (BSI) as amended or revised from time to time, or such other standards as approved by SYABAS.
b. Bulk Meter
A meter measuring water all or part of which is subsequently measured by one or more sub-meters.
c. Consulting Engineer
A professional engineer who is registered with the Board of Engineers, Malaysia and whose registration is still valid when making any submission.
d. Consumer
A person who is supplied with water from the pubic main or a person who is otherwise liable for the payment of charges for the supply of water and includes an occupier.
e. Licensed Plumber
A plumber who is registered with JKAS to implement water plumbing works.
f. Meter
Any appliance, equipment or device used for the purpose of measuring, ascertaining, regulating or estimating the amount of water consumed, supplied or used.
g. Meter stand
The position where a meter is installed.
h. Premises
Any building, land and any tent or structure.
i. Plumbing system
All pipes, tanks, valves and fittings from the public main to and within the premises of the owner or occupier.
j. Sub-meter
Any meter which measures water which has already metered since leaving the public main.
k. Water fittings
Pipes (other than the public mains), taps, cocks, valves, ferrules, meters, cisterns, baths, water closets, water heaters, telemetering system and other apparatus or appliance used in connection for the supply or use of water.
1.3 STANDARDS AND SPECIFICATIONS
All materials and water fittings used in the construction of any of the works described in these guidelines shall comply with the requirements specified in the latest edition of any applicable approved standard and the specification issued by SYABAS.
In case there is any discrepancy between the approved standard and specification of SYABAS the latter should take precedence.
1.4 INTERPRETATION OF GUIDELINES
Every design proposal shall meet the underlying objectives of these guidelines of:-
• Reliability
• Ease of Maintenance • Quality of Work • Energy Efficient
In this guidelines, the term “shall” is used in reference to standardized design parameters or requirements where departures from which are not normally permitted.
The term “should” is used in reference to suggested design parameters or requirements and the consulting engineer is expected to exercise sound professional judgment in deciding whether to depart from the suggested parameters. The consulting engineer would be expected to justify such departures in terms of cost and improved engineering performance.
2.0 PLANNING FOR WATER SUPPLY
2.1 GENERAL
In the planning for the water supply for any development, the following factors shall be considered:-
a. The requirement of SYABAS.
b. The estimated daily demand and the maximum flow rate. c. The location of the available supply.
d. The quantity and pressure of the available supply. e. The water storage capacity if required.
f. The pumping system if required.
g. No temporary water supply will be granted by SYABAS. SYABAS will only provide water supply for construction purposes.
h. The planning and design of water supply systems shall seek to optimize available energy/ water pressure.
2.2 DEVELOPMENT PROPOSALS
2.2.1 General
Development proposals shall comply with the following requirements:-
a. Proposals shall be prepared and submitted by the consulting engineers/ town planners.
b. Types and numbers of development units and the total development area shall be shown clearly.
c. Contour lines shall be shown clearly on the plan at 5 m intervals. d. Key plan and location plan shall be shown on the layout plan. e. Levels shall be based on Ordnance Datum Level (ODL).
f. Coordinates and bearings of boundary shall be stated.
2.2.2 Reservoirs and Tanks
a. The water reservoir and tank sites shall be placed at:-
i. The highest ground area in the proposed development. ii. Level grounds and not on slopes.
iii. Rectangular site area.
b. Dedicated access (entrance/ exit) shall be provided to reservoir/ tank and pumping station.
c. All slopes shall be constructed within the reservoir/ tank and pumping station reserves for ease of maintenance. Fencing shall cover all slopes with sufficient setback for drainage.
d. All land on which waterworks are built shall be surrendered to SYABAS, who will then hand over to the State Government. The land shall include access road, main infrastructure, slopes etc.
e. Should the water pressure from the connection point to the highest development area be insufficient, one or more suction reservoir/ tank and pumping station sites shall be provided whether inside or outside the proposed development area at the expense of the developer. The pumping head shall not exceed 75 m for each pumping stage.
f. The difference between the highest and lowest Finished Platform Level within the development area shall not exceed 30 m. If it exceeds 30 m, the concept of low level and high level service reservoirs/ tanks shall be considered.
g. The developer shall be responsible to carry out any landscaping works and architectural design if required by the local authorities.
2.2.3 Site Dimensions for Reservoirs and Tanks
For any development, the minimum site dimensions for suction reservoir/ tank and pumping station, service reservoir/ tank and the combination of the aforementioned are shown in Table 2.1, Table 2.2 and Table 2.3 respectively.
Table 2.1 : Minimum site dimensions for suction reservoir/ tank and pumping station
Water Demand (l/d) Site Dimensions (Minimum)
≤ 45,000 20 m x 25 m 45,001 – 227,000 20 m x 25 m 227,001 – 454,000 25 m x 30 m 454,001 – 680,000 25 m x 30 m 680,001 – 900,000 30 m x 35 m 900,001 – 1,135,000 35 m x 40 m 1,135,001 – 2,270,000 30 m x 45 m 2,270,001 – 3,405,000 45 m x 55 m 3,405,001 – 6,810,000 60 m x 65 m 6,810,001 – 13,620,000 75 m x 80 m
> 13,620,000 To be approved by SYABAS but
subject to a minimum of 90 m x 95 m
Note: Dimensions in the above table are excluding the areas of office, storeroom, toilet and quarter. Please refer Clause 3.4.3.a for details.
Table 2.2 : Minimum site dimensions for service reservoir/ tank Site Dimensions (Minimum) Reservoir/ Tank
Capacity
Ground Reservoir/ Tank Elevated Reservoir/ Tank
≤ 45,000 20 m x 20 m 45,001 – 227,000 20 m x 20 m 227,001 – 454,000 25 m x 25 m 454,001 – 680,000 30 m x 30 m 680,001 – 900,000 30 m x 30 m 900,001 – 1,135,000 35 m x 35 m 1,135,001 – 2,270,000 40 m x 40 m 2,270,001 – 3,405,000 45 m x 45 m 3,405,001 – 6,810,000 60 m x 60 m 50 m x 95 m 6,810,001 – 13,620,000 75 m x 75 m 55 m x 125 m > 13,620,000 To be approved by SYABAS but subject to a
minimum of 90 m x 90 m
To be approved by SYABAS but subject to a minimum of 80 m x 130 m Note: Dimensions in the above table are excluding the areas of office, storeroom, toilet
Table 2.3 : Minimum site dimensions for the combination of suction reservoir/ tank, pumping station and service reservoir/ tank
Water Demand (l/d) Site Dimensions (Minimum)
≤ 45,000 25 m x 50 m 45,001 – 227,000 25 m x 60 m 227,001 – 454,000 30 m x 65 m 454,001 – 680,000 35 m x 70 m 680,001 – 900,000 35 m x 70 m 900,001 – 1,135,000 35 m x 75 m 1,135,001 – 2,270,000 40 m x 90 m 2,270,001 – 3,405,000 45 m x 100 m 3,405,001 – 6,810,000 50 m x 115 m 6,810,001 – 13,620,000 55 m x 145 m
> 13,620,000 To be approved by SYABAS but
subject to a minimum of 55 m x 260 m
Note: Dimensions in the above table are excluding the areas of office, storeroom, toilet and quarter. Please refer Clause 3.4.3.a for details.
3.0 EXTERNAL WATER SUPPLY SYSTEM
3.1 APPLICATION FOR SOURCE OF WATER SUPPLY
a. The owner or developer shall apply to SYABAS through their consulting engineer together with the following:-
i. Appointment letter to the consulting engineer from the owner or developer, and the consulting engineer’s registration letter with the BEM.
ii. Calculation of water demand according to SYABAS requirements as shown in Table 3.1.
iii. Approval letter and plans from the local authority. iv. Three (3) sets of Key Plan and Location Plan.
v. Three (3) sets of Site Plan, with a minimum scale of 1:500 showing the existing and proposed layout of reticulation mains, lot numbers, adjacent lot nos., house numbers and landmarks.
vi. Three (3) sets of Layout Plan complete with contour lines and proposed land development levels (in metre ODL).
vii. All plans/ drawings submitted shall be of A1 size.
b. Application with water demand of more than 50,000 litres per day shall be made directly to the Development Department, SYABAS Headquarters.
c. Application with water demand of less than 50,000 litres per day shall be made directly to the respective SYABAS District Office.
3.2 CONCEPT DESIGN SUBMISSIONS
a. For development with water demands exceeding 4.5 million litres per day and to be developed in phases or where pumping station is required, the Concept Design Report for the entire development shall be submitted to SYABAS.
b. Two (2) sets of Concept Design Report shall consist of the following:- i. General description about the project.
ii. Water demand table according to the type of development for the entire project. iii. Water demand computation table according to phase and type of development
including the years for each development phases.
iv. Supply zones for the development phases from service reservoirs/ tanks.
v. Hydraulic calculations for main pipes for peak flow condition from supply source to storage reservoir/ tank, incoming main, size and level of suction reservoir/ tank, pumping main, size and level of storage reservoir/ tank and residual pressure in the pipes for the particular supply zone.
vi. General brief and schematic plan of the overall water supply system showing nodal and pipe data. Flow and pressure readings for nodes and pipes shall be indicated. c. All plans/ drawings submitted shall be of A1 size.
3.3 DETAILED DESIGN SUBMISSIONS
a. The detailed design shall be in accordance with the requirements of the development phases.
b. A copy of SYABAS Standard Specifications shall be included.
c. Two (2) sets of Detailed Design Report shall be submitted by the consulting engineer. d. Three (3) set of drawings of A1 size shall be submitted for approval.
e. The submission shall be accompanied with one (1) no. CD containing the soft copy of all drawings relating to the water supply system, in AutoCAD format and the calculation data. There shall cover the following:-
i. Reticulation system layout plan.
ii. Symbols used shall be those as shown in the SYABAS’ Standard Drawings attached.
iii. Reservoir/ tank and pumping station layout plan. iv. Details of reservoir/ tank and pumping station. v. Plan and profile of incoming main pipe.
vi. Standard drawings.
vii. Hydraulic calculation data for reticulation system.
f. Drawings, calculations and works specifications shall be endorsed by a consulting engineer appointed by the owner or developer.
3.3.1 Civil Works
Each design proposal shall consist of the following:- a. Brief description for that particular phase.
b. Water demand table showing the types of development, calculations of reticulation pipe design for the cases of peak flow, fire flow and average flow, calculations for levels and size of reservoir/ tank and pumping system calculations.
c. Detailed calculations showing that the pipes are able to withstand the expected design traffic load with a minimum of 1.0 m depth of cover, well compacted with suitable backfill materials.
d. Calculation and sizing of scour pipe for the reservoir/ tank. e. Storm drainage system design calculation.
f. Detailed layout plan showing the main reticulation pipe system, that are coloured according to:-
i. Types and sizes of pipes.
ii. Location, type, size and BWL/ TWL for reservoir/ tank. iii. Pumping station, including drainage.
g. Detailed layout plan of reservoir/ tank showing location, side views, top and sectional views, details of levels, incoming water pipe, outgoing water pipe, overflow and scour pipes, valves locations, level indicator, ventilation system and ladders for reservoirs/ tank and security fencing.
h. Floor plan, side and sectional views of pumping station showing the pump locations, arrangement of pumping system including suction pipe from suction reservoir/ tank to pumps, pumping mains, pipe fittings, pipe trenches, motor, switchboard surge suppression system and details of levels.
i. Detailed drawing showing the supports, foundation arrangements with base plate dimensions and the positions of all foundation bolts and pipe connection, chequered plate and all necessary information for the complete design.
j. Structural design including the design calculations and design criteria for pumping station and reservoir/ tank endorsed by a consulting civil engineer.
k. The hydraulic calculations for reticulation system shall include the following information:-
Pipe Details Pipe No. From Node Node To Length (m) Dia. (mm) HWC HL (m) HL/1000 Velocity (m/s) Node Details Node No. Flow (l/s) Elev (m.ODL) HGL (m.ODL) HSL (m.ODL) Residual Pressure (m) Where:-
HWC = Hazen William Coefficient HL = Head Loss
HGL = Hydraulic Grade Line HSL = Highest Supply Level
3.3.2 Mechanical and Electrical Works
The submission of detailed design and installation for mechanical and electrical works shall be as per Clause 7.2 and 6.2 respectively. It shall be submitted to SYABAS within four (4) weeks from the approval date of the detailed design of the civil works. The mechanical and electrical system design considerations shall be as required in Chapters 6.0 and 7.0. The design and calculation report shall be prepared and endorsed by consulting engineer. Approval from SYABAS shall be obtained before any work may commence at site.
3.3.3 Geotechnical Works
Each design proposal shall consist of the following:-
a. Soil Investigation Report
b. Geotechnical Interpretation Report
c. Geotechnical Design Report which shall include the following:- i. Subsoil conditions of the project site.
iii. Selection of foundation type.
iv. Design calculations for foundation of reservoir/ tank and pumping station including calculations for long term settlement and short term settlement. v. Detailed drawings for foundation of reservoir/ tank and pumping station. d. When slopes are encountered adjacent to the reservoir/ tank or pumping station, the
followings shall be included in the Geotechnical Design Report:-
i. Detailed drawings for earthwork which shall show the cross sections of critical slopes and cut/ fill sections within the reservoir/ tank or pumping station reserve and including areas 100 m beyond the site boundary.
ii. Selection of slope surface protection and erosion control.
iii. Slope stability analysis except for slopes that fall under Clause 3.4.4.b.vii. iv. Selection of slope stabilization method, if relevant, and detailed drawings and
design calculations of all slope stabilization measures. e. Geotechnical design considerations as required in Clause 3.4.4.
3.4 DESIGN GUIDELINES
3.4.1 Water Pipes
a. Hydraulic Requirements
i. The reticulation system shall be designed as per the following flow conditions:-
• Peak flow
• Combination of average and fire flow • Summary of both flow conditions above ii. Hazen-William Coefficient C shall be as per Table 3.2.
iii. Head loss gradient shall be less than 2/1000 during peak flow condition.
iv. Peak factor of average flow for incoming flow to reservoir and reticulation system shall be 1.2 and 2.5 respectively.
v. The following residual pressures shall be achieved:-
• Each node shall have a minimum residual pressure not less than 7.5 m
above the highest supply level during peak flow condition. This is applicable
to development where the source of water is drawn directly from SYABAS main.
• Each node shall have a minimum residual pressure not less than 4.5 m
above the highest supply level during peak flow condition. This is applicable to development where the source of water is drawn from the developer’s storage reservoir/ tank with the hydraulic calculations based on the BWL.
• Each node shall have a minimum residual pressure not less than 7.5 m
above the platform level, for combined average flow and fire flow condition.
• Each node shall have a maximum residual pressure not exceeding 30 m for
the two flow conditions analysed. Pressure Reducing Valve shall be provided where the residual pressure exceeds 30 m.
vi. Fire flow requirement, location and type of hydrants shall be recommended by BOMBA.
vii. Reticulation pipe size shall be subject to the hydraulic design for peak flow requirements and for pipe system with hydrant, the pipe size shall be determined by the hydraulic requirements and minimum pressure required for fire fighting and average flow condition. For pipes with hydrant, a minimum pipe size of 100 mm diameter shall be applied except the last 91 m before pipe end. Hydrant shall be installed at least 91 m before any pipe end.
b. Pipe Laying Requirements
i. All pipes shall be laid at locations which are easy for maintenance works and the cost of repair and rehabilitation works shall be considered.
ii. Twin pipes shall be installed on both sides of road shoulder should there be more than ten (10) units of houses/ shops in a row for that particular road. The main pipe shall be subject to the hydraulic and fire fighting requirements.
iii. The types of pipes used shall comply with Table 3.3 and 3.4. iv. Pipe dead ends shall be installed with isolating valve or hydrant.
v. The pipes shall be buried in sufficient depth, well compacted with suitable backfill materials and able to withstand the expected design traffic load according to the standard pipe bedding details in the attached SYABAS Standard Drawings.
vi. Under all circumstances, water pipes shall be laid above sewers with a minimum vertical clearance of 1 m.
vii. Hydrant pipeline shall be installed separately from the domestic pipeline in any area with apartment/ condominium, factory, complex, office, commercial complex, institution and school, where the water demand does not exceed 2.0 million litres per day except for low-cost flats built by the Government. Water meter shall be provided for both of the hydrant and domestic pipelines.
c. Valves and Utilities
i. All valves shall comply with prevailing SYABAS requirements.
ii. All isolating/ regulating and scour valves shall be of flange ended sluice type for pipe diameter up to 400 mm and of flange ended butterfly type for pipe diameter 450 mm and above. The in-line valves shall be installed at a maximum of every 2000 m interval of incoming main.
iii. The size of isolating valve shall be at least the size of the pipeline. However for pipe diameter of 900 mm and above, the isolating valve can be one size smaller than the pipe size.
iv. Scour locations and sizes shall be designed such that the pipelines can be scoured within three (3) hours.
v. Full bore scour point shall be provided not greater than 5 km apart at low points near river/ big drain. A self cleansing velocity of greater than 0.6 m/s shall be achieved.
vi. Scour valve sizes shall be as follows:-
• For pipe size 150 mm - 400 mm dia. - 100mm flange ended • For pipe size 450 mm - 550 mm dia. - 150mm flange ended • For pipe size 600 mm - 750 mm dia. - 200mm flange ended • For pipe size 800 mm - 1000 mm dia. - 250mm flange ended • For pipe size 1050 mm - 1200 mm dia. - 300mm flange ended • For pipe size 1300 mm dia. and above - 450mm flange ended
vii. Air valve sizes shall be as follows:-
• For pipe size 150 mm - 300 mm dia. - 50 mm double orifice type • For pipe size 350 mm - 550 mm dia. - 80 mm double orifice type with
flange ended isolating valve
• For pipe size 600 mm - 800 mm dia. - 100 mm double orifice type
with double flanged isolating valve
• For pipe size 850 mm - 1200mm dia. - 150 mm double orifice type with
flange ended isolating valve
• For pipe size 1300 mm dia. and above - 200 mm double orifice type
with flange ended isolating valve
viii. Sampling box with pressure gauge shall be provided as per Table 3.5. ix. Water usage for a NRW zone shall be limited to 1,000,000 litres per day.
x. District Meter Zone (DMZ) chamber shall be provided as per Table 3.6 within each hydraulic zone.
xi. Constant flow valve shall be installed on the incoming pipe to the suction reservoir/ tank of condominium, apartment and office to limit the flow rate at 20 hours per day whenever the residual head at the inlet of the reservoir/ tank exceed 15 m. The developer shall submit the characteristic curve/ chart of the constant flow valve to SYABAS for approval.
3.4.2 Reservoirs and Tanks
a. Storage Capacity
i. The storage capacity requirements for reservoirs/ tanks shall be as per Table 3.7 ii. The preferable volumetric ratio of suction reservoir/ tank : elevated storage
reservoir/ tank shall be 1:2. However, a proportion between 1:1 and 1:2 may be considered.
b. Hydraulic Requirements
i. For hilly development, the concept of high, medium and low hydraulic zone shall be adopted where viable.
ii. Design of reticulation system supplied from reservoir/ tank shall be based on the reservoir’s BWL and the minimum residual pressure shall be 4.5 m above HSL. iii. The following residual pressure requirements shall be satisfied:-
• Minimum residual pressure at reservoir/ tank’s TWL shall not be less than
4.5 m, where the connection source of incoming main has no connection to any other reticulation main.
• Minimum residual pressure at reservoir/ tank’s TWL shall not be less than
7.5 m where the incoming main has direct connection to reticulation pipe.
• Maximum residual pressures above HSL at any case shall not exceed
15 m for gravity fed reservoirs/ tanks and 5 m for pumping fed reservoirs/ tanks.
c. Boundary Setback
Setback from the edge of structural foundation shall be flat all-round with at least 6.0 m for ground reservoir/ tank and pumping station structures and 9.0 m for elevated reservoir/ tank structure. Minimum distance between two (2) structures shall be 3.0 m.
d. Materials and Measures
i. Reinforced concrete reservoir is preferred and suction reservoir/ tank shall be reinforced concrete. However, storage reservoir/ tank of other material may be used, subject to the approval by SYABAS.
ii. Storage reservoir/ tank with a capacity of more than 454,000 litres shall be of reinforced concrete.
iii. The usage of storage reservoir/ tank with a capacity of less than 454,000 litres built with other materials as approved by SYABAS are allowed until year 2010. After year 2010, all the storage reservoir/ tank shall be of reinforced concrete.
iv. Reinforced concrete elevated storage reservoir/ tank shall not exceed the capacity of 4.5 million litres. Capacity of elevated storage reservoir/ tank of other materials shall be subject to the approval of SYABAS.
v. The effective water depth for RC reservoir/ tank shall be not more than 5 m for capacity of less than 4,540,000 litres and 7 m for capacity of 4,540,000 litres and above. The water depth for non RC reservoir/ tank shall not be more than 5 m.
e. Pipeworks Inside Reservoirs and Tanks
i. All pipes in reservoir/ tank shall be of stainless steel, ductile iron painted with suitable anti-corrosion paint system or other materials as approved by SYABAS. ii. All vertical pipes shall be anchored and supported with stainless steel
brackets, steel bolt and nut bolted into the wall of the reservoir.
iii. Overflow pipes shall be at least one size larger than the inlet pipe diameter and not smaller than the outlet pipe diameter.
iv. The scour pipe shall be designed to empty the full capacity of reservoir within six (6) hours.
v. For gravity flow, the inlet pipe at the reservoir/ tank shall be of side or bottom inlet while for pumping supply, the inlet pipe shall be of top-inlet (bellmouth). The outlet pipe shall be of side or bottom outlet.
f. Control Valves
i. All incoming mains to the suction reservoir/ tank and gravity flow to the service reservoir/ tank shall be controlled by a mechanical control valve while the incoming pumping main shall be electrodes controlled.
ii. Inlet control valve shall be of ball float valve type for mains size up to 300 mm diameter. An additional inspection manhole with a suitable size for maintenance purposes shall be constructed directly on it. Inspection manhole shall be fitted with safety railing and covered with stainless steel chequered plate.
iii. For incoming main of size above 300 mm, a one way flow full bore altitude valve complete with T-pot strainer and by-pass installed in one common chamber shall be used. Butterfly valves shall be used for isolation and by-pass purposes.
iv. The altitude valve shall be of diaphragm or piston type for sizes of less than 450 mm diameter and of piston type for sizes of 450 mm diameter and above. v. The control valves shall be fitted with sluice valves/ butterfly valves for
isolation and maintenance purposes.
vi. All by-pass pipes shall be of the same size of the incoming pipe.
g. Pipe Strainers
i. All incoming mains to the suction reservoirs/ tanks and gravity flow to the service reservoirs/ tanks shall be fitted with pipe strainers.
ii. A pipe strainer shall be fitted after the sluice valve and installed together in a common valve chamber. The size of the valve chamber shall be constructed to suit the fittings of the sluice valve and pipe strainer.
iii. The strainer shall be of 10 ~ 15 mesh stainless steel screen (net).
h. Miscellaneous
i. External stairs of reservoir/ tank shall be of reinforced concrete and shall be fenced. All stairs shall have brickwall enclosure complete with mild steel doors. Stairs inside the reservoir/ tank shall be of reinforced concrete or stainless steel (SS304). All stairs shall be fixed with safety railing.
ii. Two (2) nos. or more ladders shall be provided for reservoir/ tank with a capacity of more than 9.1 million litres.
iii. All reservoirs/ tanks shall be fitted with ‘Dial’ type level indicators. The size of level indicator for ground reservoir/ tank and elevated reservoir/ tank shall not be less than 600 mm diameter and 900 mm diameter respectively. Only stainless steel cable (tangle-free design) shall be allowed.
iv. Perspex glass covers shall be provided on the roof of reservoir/ tank.
v. All valve chambers shall protrude above the ground level not more than 300 mm.
vi. Site drains and overflow drains shall be designed as per Table 3.8.
vii. Security fence for reservoir/ tank and pumping station area shall be built as per SYABAS Standard Drawings attached, and the reserve’s boundary shall be marked with boundary stones at 6 m interval.
viii. All level ground within the reservoir/ tank and pumping station compound shall be premixed as per Table 3.9.
ix. Reservoirs/ tanks shall be painted as per SYABAS Specifications.
x. Top water level, bottom water level and capacity of the reservoir/ tank shall be printed on the reservoir/ tank’s wall.
3.4.3 Pumping Stations
a. General
i. Platform levels of pumping stations and suction reservoirs/ tanks shall be designed above 100 years ARI flood level.
ii. Pumping station shall be of reinforced concrete and bricks with reinforced concrete roof or roof tiles. Roof tiles can only be used for pumping station where the pumping capacity does not exceed 100 m3
/hr. If roof truss is to be used, the truss shall be of steel type.
iii. All pumping stations shall be equipped with toilet and sewerage system.
iv. Pumping station with pumping capacity exceeding 50 m3/hr shall have office/ store room.
v. Pumping station with pumping capacity exceeding 10 Mld shall be equipped with two (2) unit quarters with three (3) bedrooms. Floor area of each quarter shall not be less than 65 m2.
vi. Security grilles shall be provided on the inside of the pumping station window. vii. Heavy duty floor tiling shall be provided.
viii. Ceramic wall tiling shall be provided up to 1.5 m height. ix. All windows shall be of steel-casement type.
x. All suction, discharge pipes and fittings shall conform to Table 3.3. All pipes shall be laid in trenches and well anchored.
xi. The minimum width of trenches shall be the size of pipe laid plus 300 mm space on each side of the pipe. All trenches shall be well drained and covered with hot dipped galvanised grating or chequered plate. Trenches built below the drain level shall be provided with pump sump complete with isolator point and earth leakage relay or RCD.
xii. All exposed pipes and fittings shall be painted as per SYABAS requirements. xiii. Main switchboard shall be compartmentalized and located away from water
pipes. Minimum clear distance between the main switchboard to the wall shall be 1.5 m.
xiv. Minimum clear distance between two (2) pump sets shall not be less than 1.0 m.
xv. All pumping stations shall be provided with fire extinguishers, first aid kits and safety procedures.
xvi. The pumping station shall be painted and marked as per SYABAS Specifications.
b. Pump Plinths
i. Pumpset shall be rigidly fixed in position on its foundation and shall be free from vibrations. The design of the foundation shall comply with the following criteria:-
• The pumpset foundation shall be sufficiently strong for its load.
• It shall be sufficiently strong and heavy for suppressing any vibrations.
ii. A good practice is to fix the pumpsets on concrete block, in reasonably good firm ground. The following standard depths for pumps with various powers shall be followed:- • 7.5 - 15.0 kW - 200 mm to 250 mm • 15.0 - 40.0 kW - 250 mm to 450 mm • 40.0 - 55.0 kW - 450 mm to 600 mm • 55.0 - 75.0 kW - 600 mm to 750 mm • 75.0 - 100.0 kW - 750 mm to 1000 mm
iii. In practice, for pumps with powers above 75.0 kW, foundation plinths shall be specially designed based on the following standards:-
• For electric motor driven pumps, the weight of an independent foundation
shall be at least three times more than the machine kerb weight of the pumpset.
• When anti-vibration material such as rubber, spring etc; is used between
the common base plate for pump and the prime mover, and the foundation, the weight of foundation can be reduce to half of the standard weight.
• Where any pipe of the pumping system passes through a building wall, pipe
bellow or anti-vibration material shall be employed to prevent the vibration from transmitting to the building.
iv. Apart from depth, the size of foundation plinth shall have a minimum border of 100 mm to 150 mm all round while the top of the plinth shall be 100 mm to 150 mm above the floor. The concrete mix for the plinths shall be Grade 25.
3.4.4 Geotechnical Considerations
a. Reservoir, Tank and Pumping Station Buffer Zones for Slopes
i. The setbacks or the distance from the toe or the crest of respective adjacent slopes to the edge of reservoir/ tank and pumping station structures shall not be less than 9 m.
ii. The distance between the crest of a slope and any water pipes, water retaining structures, retention ponds, etc shall not be less 5 m.
iii. Berms shall be formed on slopes at every 5 m vertical interval. For rock cut in sound and strong rock such as grade I or II granite (BS 5930:1999 - Code of Practice for Site Investigations), the berm interval may be increased to 9 m. The minimum berm width is 1.8 m.
iv. The reservoir/ tank and pumping station buffer zones for slopes are shown in Figure 3.1.
b. Slope Stability Analysis
i. Except provided under Clause 3.4.4.b.vii below, all slopes whether on cut or fill section shall be analysed for slope stability. In the analysis, groundwater conditions and potential external loadings shall be considered.
ii. The required factors of safety (FS) for slope stability are 1.5, 1.2 and 1.1 for normal groundwater conditions, 10-year return period rainfall and the worst groundwater conditions respectively.
iii. For natural slopes or existing manmade slopes more than 10 years old, the minimum values of the aforesaid FS may be reduced to 1.2, 1.1 and 1.0 respectively.
iv. For new and existing rock slopes, the above respective FS in clause ii and iii shall be applied.
v. Geological mapping and interpretation shall be carried out to analyse the stability of rock slopes.
vi. The modes of potential failures such as wedge, toppling and/ or plane failures shall be identified and suitable rock supports shall be provided as suggested in Table 3.10.
vii. Slope stabilization measures shall be required when the FS is not adequate in order to achieve the FS required above.
viii. Slope stability analysis may not be required when:-
• Height of fill slope that does not exceed 10 m and slope gradient is
gentler than 1:2 (v:h) with 1.8 m berm at every 5 m vertical interval. The fill is formed of well compacted suitable material having SPT N (no. of blows) > 8.
• Height of cut slope that does not exceed 10 m and slope gradient is
gentler than 1:1.5 (v:h) with 1.8 m berm at every 5 m vertical interval. The cut is in ideal soils of silty to sandy nature having SPT N > 8.
• Rock cut slope that does not exceed 10 m high and slope gradient is
gentler than 4:1 (v:h) in sound rocks such as Grade I or II granite, free from loose or unstable blocks or fragments.
c. Drainage Provisions
i. All slopes shall be provided with subsoil drainage such as horizontal drains:-
• At the toe of the slope.
• Where the presence of water bodies (for example, water catchment
area, sewers, drains and water mains) is above the slope.
• Groundwater level is uncertain or likely to be higher than the design
value.
• Drainage of groundwater is hindered by slope surface protection
works such as shotcrete (sprayed concrete).
ii. Berm drains and interceptor drains shall be provided on the berms and at the crest of the slope respectively. The drains shall be cast-in-situ and steel reinforced. All drains shall be designed as per Table 3.8.
d. Slope Surface Protection
i. All slope surface shall be fully (closed) turfed or protected against erosion upon completion of reservoir/ tank and pumping station construction. The grass shall be hardy, have extensive and strong root system which is effective for erosion control and perennial (long lasting) such as cow grass,
Vetiver grass (Vetiveria zizanionides) or other grass with equivalent morphological, physiological and ecological characteristics.
ii. Good agricultural practices such as introduction of topsoil, correct planting techniques and quality control shall be carried out for vegetation on the slopes. New turf shall be watered in the dry season, turf shall not be placed on very hard ground before introduction of topsoil and horizontal grooving shall be formed before turfing.
iii. On difficult or unusual sites, which cannot support plant growth, such as hard soil, acidic soil and steep slopes, suitable slope surface protection method such as special treatment using geomat or guniting or other methods approved by SYABAS shall be used.
iv. Rock supports effective to the mode of potential failures such as wedge, toppling and/ or plane failures as identified in Table 3.8 shall be provided. v. All loose rock fragments shall be scaled. Fractures rock zones susceptible to
erosion or rocks susceptible to deterioration shall be protected by a suitable method such as shotcrete with proper drainage weepholes.
e. Reservoir, Tank and Pumping Station Foundation
All reservoirs/ tanks and pumping stations should preferably be founded on competent cut ground otherwise deep foundation such as pile foundation shall be provided.
3.5 MATERIALS
a. All materials used for water supply system shall have the approval from SYABAS. SYABAS reserves the right to inspect the materials to be used before installation. Unapproved materials/ products including the works completed using the unapproved materials shall be cleared from the site. Otherwise, the development will not be taken over by SYABAS.
b. The types of incoming mains (without tapping) are as shown in Table 3.3. c. The types of reticulation pipes are as shown in Table 3.4.
3.6 CHECKLIST
The checklist shall be completed and endorsed by a consulting engineer and shall be attached together with the submission document. The design checklist of External Water Supply System is shown in APPENDIX C.
Table 3.1 : Estimation of water consumption
Residential Daily Water Usage (l/d)
Low cost house and low cost flat
Medium low cost flat and medium cost house Single and double storey terrace house Apartment/ condominium
Single and double storey semi detached house Single and double storey bungalow (Additional
450 litres per room if more than 4 bedrooms)
1,000 1,500 1,500 1,500 2,000 2,000 /unit /unit /unit /unit /unit /unit Commercial 2,000 1,500 1,000 50,000 10,000 450 1,500 1,500 1,500 1,000 /unit /storey /100m2 /unit /unit /stall /stall /stall /room /100m2
According to daily water usage (Note 1) Single storey shop
Multiple storey shop house Office
Petrol station – a) With car washing bay b) Without car washing bay Market – a) Dry stall
b) Wet stall Hawker Centre
Hotel
Shopping complex
Industrial lots Light industrial workshop
Terrace factory Warehouse 1,500 5,000 1,500 /unit /unit /unit Public and Social
Hospital Mosque/ Surau Community Hall Club House Balai Raya Day school Boarding school Institution Kindergarten 1,500 50 25,000 50,000 2,000 50 250 25,000 30 /bed /person /unit /unit /unit /student /student /ha /child
Note:-
1. The consulting engineer shall estimate and justify the water demand consumption, otherwise 75,000 l/d for every hectare of land shall apply.
2. If the premises category/ usage is not stated in Table 3.1, further information shall be obtained from SYABAS.
Table 3.2 : Hazen-William Coefficient C for various pipe materials
Table 3.3 : Materials for incoming main/ main pipe (without tapping)
Conditions Incoming Main Pipe Materials
Non-corrosive soil - Mild Steel (for diameter ≥ 700 mm)
(note 1) - Ductile Iron (note 3)
Corrosive soil/ coastal area
- HDPE - ABS - GRP
- Ductile Iron with thicker zinc coating (note 3) - Mild Steel (for diameter ≥ 700 mm) (note 1 & 2)
- Pumping main
- Gravity main in undulating area, sloping/ hilly area
- Mild Steel (for diameter ≥ 700 mm) (note 1) - Ductile Iron (note 4)
Under roadways
- Mild Steel (for diameter ≥ 700 mm) (note 1) - Ductile Iron (note 3)
- HDPE/ ABS/ GRP with RC pipe sleeve
Note :
1. Mild steel pipes with diameter of below 700 mm complete with full internal lining protection acceptable to SYABAS and with CCTV confirmation may be considered. Alternatively, flange jointed mild steel pipes are acceptable.
2. Mild steel pipes shall not be used for corrosive soil, however it can be considered if protected with anodic/ cathodic protection.
3. Ductile iron pipes shall be push-in jointed complete with PE wrapping.
4. Ductile iron pipes shall be flange jointed or restraint tie bar jointed complete with PE wrapping.
5. All plastic pipes shall be of PN 12 and above.
6. All pipeworks shall be as per SYABAS Specifications.
Type of Pipe Hazen-William Coefficient C
Ductile Iron (cement lined) Steel (cement lined)
HDPE/ ABS/ GRP
100 100 120
Table 3.4 : Materials for reticulation pipes
Conditions Reticulation Pipe Materials
Corrosive soil, coastal area, ex-mining land, etc
- HDPE - ABS - GRP
- Ductile Iron with thicker zinc coating - Mild Steel (for diameter ≥ 700 mm) (note 1 & 2)
Fully industrial area, commercial,
flats, condominium and shop houses - Ductile Iron
Residential area and mixed developement - HDPE - ABS - GRP - Ductile Iron Under roadways
- Mild Steel (for diameter ≥ 700 mm) (note 1) - Ductile Iron
- HDPE/ ABS/ GRP with RC pipe sleeve
Note :
1. Mild steel pipes with diameter of below 700 mm complete with full internal lining protection acceptable to SYABAS and with CCTV confirmation may be considered. Alternatively, flange jointed mild steel pipes are acceptable.
2. Mild steel pipes shall not be used for corrosive soil, however it can be considered if protected with anodic/ cathodic protection.
3. All plastic pipes shall be of PN 12 and above.
4. All pipeworks shall be as per SYABAS Specifications.
Table 3.5 : Sampling box
No. of Connections No. of Sampling Box
Below 200 Not required
201 – 1,000 1
1,001 and above
Additional 1 no. of sampling box for every 1,000
connections
Table 3.6 : DMZ chamber requirements for each hydraulic zone
No. of Connections No. of DMZ Chamber
Below 500 Not required
501 – 2,000 1
2,001 and above
Additional 1 no. of DMZ chamber for every 2,000
Table 3.7 : Storage capacity requirements for reservoirs/ tanks
Storage Requirement (day of total average daily water demand) Conditions
Reservoir (external)
Tank (within consumer premises) RESIDENTIAL, SHOPHOUSES, OFFICES, GOVERNMENT BUILDINGS AND EDUCTIONAL BUILDINGS
Demand < 1 Mld Not Required 2
Low rise (5 storey and below) development with
demand ≥ 1 Mld 1 1
High rise (6 storeys and above) development with
demand ≥ 1 Mld Not Required 2
Mixed development (low rise and high rise) with demand ≥ 1 Mld:-
a) High rise Not Required 2
b) Low rise with demand ≥ 1 Mld 1 1
c) Low rise with demand < 1 Mld Not Required 2
All developments within Putrajaya Already Provided 2
All developments within Cyberjaya 1 2
INDUSTRIAL AREA/ FACTORY, HOSPITAL, HOTELS, RESORTS AND COMMERCIAL COMPLEXES
a) Demand ≥ 1Mld 1 2
b) Demand < 1 Mld Not Required 3
MIXED DEVELOPMENT OF RESIDENTIAL,
INDUSTRIAL AND COMMERCIAL Combination of the above principles
Table 3.8 : Storm drainage system design requirements
Drain Type Design Flow
General site drainage 5 years ARI + check 100 years ARI
Overflow discharge drain to approved discharge point
5 years ARI + check 100 years ARI or
5 years ARI + Overflow whichever is the greater
Table 3.9 : Premix road pavement structures Thickness (mm) Pavement Structure
Trafficable Area Non-trafficable Area Road Base (crusher run)
Binder Course Wearing Course 250 60 40 150 60 40
Table 3.10 : Rock Slope Stabilization Measures
STABILIZATION MEASURES POTENTIAL
FAILURE TYPE
Excavation Structural Support Drainage Rockfall Control
Name (with sketch)
F la tte n S lo pe B en ch Lo ca l e xc av at io n G un ite fa ci ng P er m ea bl e (m as on ry ) fa ci ng Lo ca l s tr uc tu ra l " de nt iti on " B ut tr es s A nc ho re d w al l S tr ap D ow el B ol t A nc ho r D ra in ag e di tc h S cr ee de d (p av ed ) su rf ac e S ho rt d ra in ho le s Lo ng d ra in ho le s/ a di ts M ov e st ru ct ur e/ hi gh w ay R oc k tr ap d itc h R oc k tr ap fe nc e/ w al l N et tin g S ca lin g of lo os e bl oc ks Plane Failure √ √ √ √ √ √ √ √ √ √ √ √ Wedge Failure √ √ √ √ √ √ √ √ √ √ Toppling Failure √ √ √ √ √ √ √
Rock or Debris Fall & General Degradation
√ √ √ √ √ √ √ √ √ √ √ √ √ √ √ √ √ √ √
* Table 3.10 is extracted from “Geotechnical Manual for Slopes”, Geotechnical Engineering Office, Civil Engineering Department, The Government of the Hong Kong Special Administrative Region, 2000.
F ig u re 3 .1 : T y p ic a l re s e rv o ir / w a te r ta n k – s lo p e s c o n fi g u ra ti o n
4.0 INTERNAL PLUMBING SYSTEM
4.1 PLANS
a. Consulting Engineers shall submit three (3) sets of finalized plans of A1 size including one (1) no. CD containing the soft copy of the drawings in AutoCAD format to the respective SYABAS District for approval. The plans required are as follows:-
i. Site plan.
ii. Building plans that are approved by local Authority.
iii. Floor plan and cross section including meter location, fittings location, valves, pipeline route, etc.
iv. Detailed plan of cross sections showing tank and pump room locations. v. Schematic diagram of pipework layout.
vi. A copy of approved letter for external water supply system and a copy of approved letter for tapping point from SYABAS’ Headquarters for proposed development with demand exceeding 50,000 litres per day.
b. For building of three (3) storeys and below without pumping system, two (2) sets of calculations by design chart method shall be submitted by the architect, mechanical engineer, civil engineer or hydraulic engineer.
c. For building with pumping system or development of four (4) storeys and above, two (2) sets of hydraulic calculations shall be submitted and endorsed by mechanical or civil engineer.
d. All plans for fire fighting system shall be referred to BOMBA.
e. Fire fighting pipes shall be of red colour and domestic pipes shall be of blue colour.
4.2 TECHNICAL REQUIREMENTS
4.2.1 General
a. All plumbers trained by SYABAS will be provided with an ID card that contains personal details and photograph to ensure that only qualified plumbers are allowed to carry out plumbing installation works.
b. Tapping works shall only be conducted by Licensed Plumber Type 2.
c. All pipe installation works within a building shall be carried out by a registered plumber.
d. Only pipes, valves, tanks and other installations that have been approved by SYABAS can be used.
e. Pipe to kitchen sinks shall be drawn directly from the incoming pipe before it branches to a tank (not applicable for developments with central storage).
f. All other tapping from the incoming pipe within the premise shall only be channelled to the storage/ break tank to avoid contamination in the main pipeline.
g. Water piping system for domestic water supply, air conditioning and fire fighting system shall be separated.
h. Automatic flushing is not allowed.
i. Manual flushing or flush valve shall be used for urinal.
j. Separate pipe from storage tank shall be provided for system adopting flush valve. k. All saddle used shall have protective coating as per SYABAS requirement.
l. Saddles for High Density Polyethylene (HDPE) pipe shall be of electro-fusion tapping. m. All bolts and nuts underground shall be of stainless steel.
4.2.2 Pipes and Valves
a. Nominal size, type and class of pipes shall be stated in the drawings.
b. Detailed information including catalogues of valves shall be submitted to SYABAS. c. Minimum internal diameter for internal plumbing shall be 15 mm.
d. Usage of G.I. and uPVC pipes are not allowed.
e. Types of pipe allowed for cold-water system are shown in Table 4.1.
f. For dropper pipes with pressure exceeding 30 m head, pressure reducing valve or break tank shall be used.
g. Connection for HDPE pipe shall be of electro-fusion and butt weld. h. Control valves (ball or stop cock type), shall be installed on : -
i. All incoming pipes to suction tank and roof storage tank at 1.8 m above floor level.
ii. All outgoing pipes from suction tank in an accessible position at maximum 1.8 m above floor level.
iii. Pipes to each toilet compartment and pipes to fittings such as sink, basin, WC and urinal.
4.2.3 Water Tanks within Consumer Premises
a. Capacity
i. Generally, the effective capacity of storage tank (actual volume of water that can be drawn for usage) shall be as shown in Table 3.7 and Table 4.2.
ii. Factory with future expansion plan shall allocate sufficient space for ultimate storage requirement.
iii. Top Water Level (TWL) for suction tank and roof storage tank shall be in Ordnance Datum Level (ODL).
iv. For low cost house/ flat, water tub of minimum 120 litres shall be provided in the bathroom.
v. Separate water tank for food court in building shall be provided.
b. Pipeworks and Materials
i. Water tank with capacity of less than 4,500 litresshall have overflow pipe which shall also function as a warning pipe and shall be installed at a visible location. ii. Water tank with capacity of 4,500 litres and above shall have separate overflow
and warning pipe and shall be installed at a visible location.
iii. Overflow pipe and scour pipe shall be one size larger than the incoming pipe and not smaller than the outlet pipe.
iv. Scour pipe shall be installed underneath the tank and channelled to the nearest floor trap, sump or drain at a visible location.
v. Sampling pipe shall be provided at the water storage tank for building which provides water for food or beverage purposes.
vi. The types of tanks allowed to be used as water storage tanks in buildings are subject to the approval by SYABAS. The following materials are approved:-
• Reinforced Concrete (RC)
• High Density Polyethylene (HDPE) • Stainless Steel
• Glass Coated Steel
c. Safety and Security
i. The storage tank (including any tap fitted to the storage tank) and its ancillary equipment shall be kept properly locked at all time.
ii. All roof storage tanks shall be easily to access with proper staircase within the premises. Only spiral or walk up staircase shall be used and no cat ladder shall be allowed.
iii. There shall be proper access for removal and replacement of the storage tank without removing or damaging any part of the building.
iv. The storage tank shall be placed on flat RC slabs complete with proper drainage system. Timber and angle iron shall not be used for the support. v. The base of the storage tank shall be fully supported over its whole area by a
durable, rigid, flat and level platform sufficiently strong to withstand the weight of the cistern without deflection when filled with water.
4.2.4 Pumping Systems
a. Total pumping head shall be as per design and not more than 75 m per stage. For case where the pumping head is more than 75 m per stage, a break tank with a capacity of 11.5 m3 shall be introduced.
b. Pumping system operation shall have automatic control by stainless steel electrodes located within the suction tank and storage tank.
c. Selector switch shall be provided at the starter panel in order for the pump to be operated manually.
d. Maximum pumping rate for on duty pump shall be adequate to fill the commercial or office storage tank in eight (8) hours and residential storage tank in twelve (12) hours.
e. Suction tank shall be sized to be between 33% to 50% of daily water demand and roof storage tank shall be sized to be between 50% to 67% of daily water demand.
f. For cases where the number of pumps on standby is 200%, roof storage tank may be reduced to a size not less than 30% of daily water demand, and suction tank to have not less than 70% of storage capacity.
g. For pumping design using pressurized system where the storage is 100% in ground floor storage tank,
i. The number of pumps on standby shall be 200% of duty pumps.
iii. A standby generator shall be provided.
h. Alarm system shall be provided to give signal when the water level in the storage tank is lower than pump start level.
i. For buildings with rain water collection system, the size of water storage tank may be reduced to 75% of daily water demand.
j. For building with multi-basement lower than external road level, pumps and suction tanks shall not be located at the lowest level of the basement to avoid water contamination and damaged to pumping equipment. For building with single basement, pumps and suction tanks located at basement shall be provided with proper drainage system to prevent flooding.
4.2.5 Hot Water Systems
a. Hot water piping system shall be separated and drawn directly from the storage tank. Pumping system is only allowed after the water tank.
b. Control valve shall not be fixed at the heater outlet pipe for instant water heater.
c. Safety valve, whether using vent pipe or pressure relief valve, shall be drained to the bathroom floor trap for storage type water heater.
d. Types of pipes allowed for hot-water system are subject to approval of SYABAS. The types of pipes approved are stainless steel, copper and PP-R pipes.
4.2.6 Swimming Pools
a. Pool capacity, turnover time, rate of water cycle, rate of filtration and make-up water volume, which consists of backwash water, water displacement, and evaporation loss shall be mentioned in the drawing.
b. Detailed schematic drawing of swimming pool piping system shall be submitted to SYABAS.
c. Technical details and catalogue for pump and filter shall be submitted to SYABAS. d. Swimming pool shall be designed in order to be filled within one (1) day to three (3) days.
4.3 WATER CONSERVATION
4.3.1 General
Water shall be used efficiently and effectively at all times. Consumers are encouraged to adopt water conservation measures in all non-domestic and domestic premises and construction sites to conserve water.
4.3.2 Water Conservation Measures
a. Use of Water Saving Devices
i. Residential premises
Install constant flow regulators at wash basin taps, wash basin mixers, shower taps and shower mixers.
ii. Toilets and washrooms in all premises
Use low capacity dual flushing cisterns with capacity not exceeding 6 litres in all new premises and existing premises undergoing renovation.
iii. Toilets and washrooms in non-residential premises
• Install self-closing delayed-action taps at all wash basins and shower
points.
• Install constant flow regulators at all wash basin mixers and shower
mixers.
iv. Kitchens and cooking areas in non-residential areas Install constant flow regulators at all sink taps and mixers. v. Canteens
Install self-closing delayed-action taps at all wash basins and wash troughs. vi. Laboratories
Install constant flow regulators at all wash basins and sink taps except for safety reasons.
vii. Factories
Adopt the following measures in factories where possible and applicable:-
• Setting up of water recovery system for boilers to recover condensate
water as make-up water.
• Setting up water recycling system to reclaim water for reuse in the
production process and other non-potable purposes.
• Use of non-water cooled systems such as for cooling purposes.
b. Rainwater Harvesting System
Implement rainwater harvesting system which involves the collection, storage and distribution of rainwater from the roof of a premises.
4.4 CHECKLIST
The checklist shall be completed and endorsed by consulting engineer and shall be attached together with the submission document. The design checklist of Internal Plumbing System is shown in APPENDIX C.
Table 4.1: Internal Pipe Materials
Type of Pipe D < 100 mm dia. D = 100 mm dia.– 150 mm dia.
Communication Pipe
Stainless Steel/ HDPE (for selected suppliers only)(Note 5)/ Polysteel
Flanged Mild Steel/ Ductile Iron
Service Pipe
Stainless Steel/ ABS/ PP-R/ Copper/ Polybutelene/ Polysteel/ POB/ GRP
Flanged Mild Steel/ ABS/ Ductile Iron/ HDPE
Pumped Riser
Pipe Stainless Steel/ Copper/ Polysteel
Flanged Mild Steel/ Ductile Iron (Note 2)
Distribution Pipe
Stainless Steel/ ABS/ PP-R/ Copper / Polysteel/ POB/ GRP
Flanged Mild Steel/ ABS/ Ductile Iron/ HDPE
Note:-
1. Polysteel pipe shall subject to the quality of work inspections by pipe manufacturer.
2. Ductile iron pipe for pumped riser shall be flange ended or push-in jointed complete with restraint tie bars.
3. All plastic pipes shall be of PN 12 and above.
4. All pipeworks shall be as per SYABAS Specifications.
5. The usage of HDPE pipe as communication pipe shall be those approved by SYABAS.
