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26
APPENDIX C
TENDER FOR THE LAND AT 17 UBI ROAD 4 LOT 03652C MUKIM 23
ADDITIONAL CONDITIONS OF TENDER
(TECHNICAL)
1 General
1.1 The Successful Tenderer must in addition to the Particulars & Conditions of
Tender, observe and comply with these Additional Conditions of Tender
(Technical) in the tender of the land together with all existing buildings and
structures thereon (if any) in the Republic of Singapore (“said Property”). The
Particulars & Conditions of Tender and these Additional Conditions of Tender
(Technical) shall be read in conjunction with the technical information booklet
enclosed in the Tenders Packet. The Successful Tenderer shall also comply
with all applicable guidelines issued by the relevant competent authorities
which shall include all and any authorities (“relevant Competent Authorities”)
and Public Utility Licensees. All proposals are subject to the approval of all
relevant Competent Authorities and Public Utility Licensees.
2 Planning Parameters
2.1 Proposed Development
The subject said Property at 17 Ubi Road 4 shall be for a Car Showroom-
cum-workshop or any other Business 1 use as determined by Urban
Redevelopment Authority (“URA”). The site area is the area measured up to
the boundary lines as shown on the pre-computation plan.
2.2 Allowable Gross Floor Area (“GFA”)
Based on the site area of 4,986.30 sq m, the permissible Gross Plot Ratio
(“GPR”) should not exceed 2.0. The total GFA shall be computed in
accordance with URA’s Development Control Guidelines.
2.3 Building line/ setback
The Successful Tender shall at all times comply with the URA’s and the
relevant Competent Authorities’ requirements on the building line setback.
Notwithstanding the generality of the foregoing, the building setbacks
(including basement structures) shall be based on the boundary of the said
Property delineated on the pre-computation plan.
2.4 Building Height
The said Property shall be subject to a technical height control limit which
ranges from 30m AMSL to 35m AMSL. The Successful Tenderer is to check
27
with the relevant Competent Authorities on the standing guidelines as the
guidelines are reviewed from time to time.
The Successful Tenderer shall ensure that any and all developments,
structures and fixtures on the said Property do not exceed the maximum
allowable height limit which ranges from 30m AMSL to 35m AMSL. Such
developments, structures and fixtures include those on the roof tops of the
building (such as water tanks, lift motor rooms, TV antennae, maintenance
equipment, lightning conductors, etc) and all construction equipment and
temporary structures (such as cranes, piling rigs, etc) are subject to the same
height limit. Civil Aviation Authority of Singapore’s (“CAAS”) and Republic of
Singapore Air Force’s (“RSAF”) clearances shall be sought for the use of
crane or tall construction machineries.
The Successful Tenderer shall obtain CAAS’ and RSAF’s prior written
approval before mobilizing and/or installing any construction machineries on
the said Property. An application to CAAS is to be submitted by the
Successful Tenderer using the Crane Application Form available at URL:
http://www.caas.gov.sg/caasWeb2010/export/sites/caas/en/eServices_Forms/
Application_for Aerial_Activities/download/crane_2009.pdf.
The Successful Tenderer is to consult URA’s Development Control Group
when the detailed development plans are available.
In the event where there are any communication installations on the said
Property, the Successful Tenderer is advised to seek clearance from relevant
agencies such as Infocomm Development Authority of Singapore (IDA).
2.5 Building layout
In the event where there are modifications / A &A to the existing building, the
development must comply with the Development Control Guidelines issued
from time to time by the Competent Authority under the Planning Act (Cap
232).
2.6 Platform level
2.6.1 The platform level of the said Property is prepared approximately as
follows:
PL 103.97M – 105.31M AMSL
Slope indications and platforms levels are shown on the topographical
survey plan.
2.6.2 The Successful Tenderer shall not reduce the height of the said
Property and slope of the said Property except for the access to the
said Property subject always to the HDB’s prior written approval.
28
2.6.3 The Successful Tenderer shall seek the HDB’s prior written approval
to raise the platform level for more than one meter (1m) above the
HDB’s proposed platform level if its business operations necessitate
the need for a higher platform level.
2.7 Carparks
The Successful Tenderer shall provide carparks for the said development in
accordance with the full parking provision requirements as stipulated in the
prevailing Parking Places (Provision of Parking Places and Parking Spaces)
Rules.
2.8 Vehicular ingress / egress
The vehicular ingree / egress (the access) to the said Property shall be taken
from Ubi Road 4 as per existing position
3.0 Conditions and requirements of all relevant Competent Authorities and public
utility licensees
3.1 The Successful Bidder shall comply with all the conditions imposed by all the
relevant Competent Authorities, public authorities, public utility licensees and
persons including but not limited to the following:
(a) Pollution Control Department of the National Environment Agency (“NEA”):
i. No panel beating, spray painting and engine overhaul for motor
workshop uses.
ii. The said Property is within an estate where there are existing B1
uses. The motor workshop operators shall implement all necessary
mitigation measures to minimize nuisance impacts due to noise,
smell, fumes, vibration or dust from affecting the B1 trades in the
estate.
(b) Public Utilities Board (“PUB”):
Policy and Planning
i. The said Property is within the water catchment. A list of negative
industries which are excluded from water catchment is set out in
Annex 1.
29
Catchment and Waterways – Please Contact Mr Chee Kok Cheng at Tel
6731 3475 if need any clarifications
ii. The said Property is affected by 11.5m wide Drainage Reserve as
shown indicatively in Annex 2. The 11.5m wide Drainage Reserve
shall be excluded from the said Property.
iii. The minimum platform level for normal development shall be RL
105.0m or 300mm above the adjacent road/ground levels,
whichever is the highest.
iv. If there is any roadside drain within the site, the following
conditions shall be complied with:
1. The existing roadside drain and the scupper drainage
system within the site shall not be interfered with, in any
manner, without explicit written approval from the PUB.
2. If the Successful Tenderer proposed to fence-in the
existing roadside drains / outlet drain (if any), the owner
shall allow the PUB or its agent access to carry out
drainage works within the fenced-in portion of the roadside
drain.
3. The Successful Tenderer shall be responsible for the
structural maintenance of the fenced-in portion of the
roadside drain.
v. The minimum platform level for normal development shall be RL
105.0m or 300mm above the adjacent road/ground levels,
whichever is the highest.
vi. The Successful Tenderer shall ensure that the design and
construction of the proposed development within the site will not
cause or affect the structural integrity of the existing roadside
drains /outlet drains.
vii. The planning, design, construction activities and procedures for
plan submission shall comply fully with the requirements as
stipulated in the Sixth edition – Addendum 1 of the Code of
Practice on Surface Water Drainage and The Sewerage and
Drainage (Surface Water Drainage) Regulations 2007. Tenderers
may download the latest version of the COP from the PUB
website: http://www.pub.gov.sg/general/code/Pages/default.aspx.
30
viii. Effective erosion and sediment control measures shall be provided
by the Successful Tenderer and the Successful Tenderer’s
Qualified Person (“QP”) shall advise it to provide such effective
measures and facilities with inputs from Qualified Erosion Control
Professional (including site management system and perimeter
cut-off drain, silt traps, storage ponds, treatment plants, etc) as to
ensure clean discharge that complies with the statutory
requirement. The proposed erosion and sediment control
measures shall be submitted by a Qualified Erosion Control
Professional (QECP) to Public Utilities Board before
commencement of works. All affected watercourses shall be
desilted and cleared until completion of work. For reference, the
information can be found in the website www.pub.gov.sg/ECM.
ix. The proposed site is within Marina water catchment area. No
pollutive industries shall be sited in the development site. Stringent
pollution control measures shall be adopted in accordance with
PCD (NEA)’s Code of Practice on Pollution Control.
x. The Successful Tenderer shall make sure that there will be no
sewage, grease, oil and sewage water discharged into the drains
and all sewage shall be discharged into the sewer. No pollutive
contaminants shall be discharged into the drains leading into our
reservoir.
Water Reclamation Network – Please Contact Mr Liew Jia Yan at Tel:
6731 3876 if need any clarifications
xi. There are existing 150mm, 450mm and 600mm diameter sewers
within/in the vicinity of the proposed site. Annex 3 shows the
approximate location of existing sewerage infrastructure within/in
the vicinity of the proposed site. This plan is for reference only.
Thorough site investigation shall be carried out to determine the
exact positions and levels of the existing sewer.
xii. Any sewerage systems within the site shall not be
altered/interfered without the approval of PUB. Where diversion of
sewer is required, it shall be carried out at the Successful
Tenderer’s own cost & expense. A QP shall be engaged to submit
the diversion proposal to PUB(WRN) for approval. Details of the
diversion should be submitted to PUB(WRN) for approval before
the commencement of works.
31
xiii. If the Successful Tenderer’s intends to reuse the existing
sanitary/sewerage system, it shall ensure that they have adequate
capacity and are in good condition. A thorough investigation shall
be carried out and the inspection report shall be submitted to
PUB(WRN) for evaluation of its proposal.
xiv. Petrol and Oil Interceptor shall be provided for the workshop and
in strict compliance with the Code of Practice on Sewerage and
Sanitary Works. The discharge from the workshop into the public
sewerage system shall comply with the standards/ limits of
concentration as stipulated in the Sewerage and Drainage (Trade
Effluent) Regulations and where necessary in-house pre-treatment
plant/facilities shall be installed to ensure that the wastewater meet
the discharge standards / limits.
Water Supply Network – Please contact Mr Marwin Suhaimi at Tel: 6731
3934 if need clarifications
xv. The enclosed plan in Annex 4 shows the approximate positions of
existing and proposed watermains of 100 mm diameter and above
in the vicinity of the above site. Smaller submains to customers’
premises / properties have not been indicated. In planning for the
above site, please incorporate the following requirements:
1. Provisions shall be made by the Successful Tenderer for PUB
to lay new watermains if required, along public road reserves /
sidetables to the above site. The cost for the laying of new
watermains, if any, and connecting pipe to serve the above site
shall be borne by the Successful Tenderer.
2. Provisions should also be made by the Successful Tenderer
for the diversion of any watermains and connecting pipes
affected. The cost of diversion shall be borne by the
Successful Tenderer.
3. The positions of all the watermains as shown are approximate
only. Please determine by means of trial holes the exact
alignment and levels of all existing watermains during the
design stage and let us know whether they are affected by the
proposed works so that we can advise whether diversion is
required. If diversion is required for watermains of 300 mm dia
and below, consultation must be made at least 6 months
ahead and the cost of diversion of any watermain shall be
borne by the developer.
32
4. No structure either permanent or temporary may be erected
over any watermain. Buried watermains require a minimum
cover of one metre and adequate protection for the watermains
should be provided should the cover be removed or reduced
by the work.
5. No services shall overcross or be erected over any watermain.
Where a cable, pipe or drain undercrosses a watermain, a
clearance of 0.5 metre for watermains 300mm dia and smaller
and 1.0m for watermains 500mm dia and larger must be
provided. No manhole is allowed on top of any watermain.
There must be a horizontal clearance of 1 metre between the
manhole and watermains.
6. The Successful Tenderer shall take all necessary precautions
to safeguard and to avoid damage to all watermains. The cost
of repairs to any watermain damaged as a result of work
carried out is to be borne by the party which causes the
damage. The party will also be billed for the repair of the
mains and the estimated quantities of water lost from the
damaged mains.
7. Please inform our 24-hour Water Service & Operations Centre
at Telephone No. 6521 6488 immediately in the event of
damage to any watermain.
8. The design of the water reticulation system shall comply with
the Public Utilities (Water Supply) Regulations, Singapore
Standard CP 48 – Code of Practice for Water Services and all
other relevant statutory requirements. The modes of water
supply to be adopted are as follows:
Height of Highest Fittings Method of Supply
i) Less than 125 mRL Direct.
ii) Above 125 mRL but
below *137 mRL
Indirect supply through high level storage
tanks.
33
iii) Above 137 mRL Indirect supply through low level tank with
pumping to high level storage tanks.
(* Refers to height of inlet pipe to high level storage tanks.)
9. Notwithstanding the above modes of supply, where water is
essential for the operations of the above premises, storage
tanks of capacity equivalent to 1 day’s water requirements
shall be provided for the purpose of maintaining a continuous
supply of water in the event of supply interruption.
10. Where pumping system or storage tanks are required for the
water services, a Professional Engineer must submit the
Notification of Water Service Work together with a set of the
drawings to Water Supply (Network) Department. If all the
fittings in the water service installation are receiving direct
water supply from PUB mains, then a licensed water service
plumber shall be engaged to submit the Notification of Water
Service Work and a set of drawings to our Department prior to
commencement of the installation work.
11. PUB is presently supplying NEWater for direct non-potable
purposes such as for cooling towers, industrial processes,
general washing, landscaping, and other non-potable
purposes. All new non-domestic premises such as commercial
and industrial developments, etc, including those existing
premises undergoing addition/alteration works where it is
applicable to use NEWater are therefore required to provide a
dedicated NEWater pipe system now to facilitate the supply
NEWater when it becomes available in future. Provision shall
also be made for a NEWater storage tank to be installed within
the premises with its inlet not higher than 115 mRL and a
capacity equivalent to the 1 day’s non-potable water
requirement. There shall be no cross connection between the
PUB water and NEWater supply pipelines. Successful
Tenderer / consultants may consult PUB during the pre-
planning stage on the detailed requirements.
12. Water pipes and fittings to be used in the above site shall
comply with standards stipulated by PUB.
34
13. The detailed water requirement for the above premises shall
be submitted to Water Supply (Network) Department if it is
more than 1,000 m3/month.
14. Water conservation measures as stipulated in the Public
Utilities (Water Supply) Regulations and SS CP 48 – Code of
Practice for Water Services shall be adopted.
15. Non-potable water should be used for non-potable purposes
such as irrigation, general washing, etc whenever possible.
16. Water should be recycled wherever possible.
General Requirements
xvi. No structure/piling/retaining structure (whether temporary or
permanent) shall be sited over or close to the sewers. All new
structures shall be kept as far away from existing sewers as
possible and no nearer than the following minimum lateral
clearances from the centreline of the sewer pipe:
Sewer Pipe Diameter
(mm) Nett Clearance Required
150 to 600
(depth ≤ 3m)
1.0m from outer edge of any structure to
centreline of sewer pipe
150 to 600
(depth > 3m to 5m)
1.5m from outer edge of any structure to
centreline of sewer pipe
150 to 600
(depth > 5m)
2.0m from outer edge of any structure to
centreline of sewer pipe
xvii. It is critical to note that no building works, including preliminary
activities like trial trench, soil investigation works, earthwork,
excavation/digging, piling, ground drilling/penetration works, etc
shall commence within the required setback for the sewer until a
written clearance from PUB has been obtained
xviii. Successful Tenderer / QP must check for the presence of public
sewerage pipelines by referring to the Sewer Interpretation Plan
(SIP) which can be purchased online through the CBPU website
35
at http://www.ecitizen.gov.sg/govmall/nea_sip.html. Please note
that the sewerage information in SIPs is indicative and for
reference only. A thorough site investigation, including trial
trenches shall be carried out to determine the exact position and
levels of the existing sewers prior to commencement of any works.
xix. The Successful Tenderer shall comply with PUB’s general
requirements for protection of the existing sewers, pumping mains
and DTSS tunnels & structures and a standard advisory note to
the Agencies/QPs/Contractors on the procedure and requirements
to prevent the sewerage system from being damaged by
construction activities is in Annex 5.
xx. PUB(WRN) shall be consulted on any proposed works in the
vicinity of the existing sewerage system i.e. within the
excavation/piling works’ influence zone or a corridor of 25m from
the works to be carried out. The guideline on ‘Prevention of
Damage to The Sewerage System’ can be found in PUB website
at
http://www.pub.gov.sg/general/usedwater/SewerageandSanitaryW
orks/Pages/PreventionofDamage.aspx#Prevention. Before the
commencement of works, the Successful Tenderer /contractor is
required to submit a notification for the commencement of works
to our Network Management Branch (NMB) at least 7 days before
the commencement of any excavation works near any sewers or
sewerage system.
(c) Land Transport Authority (LTA):
i. The access of the said Property shall be taken from Ubi Road 4 as
per existing position.
(d) SP PowerGrid Ltd:
i. There are underground electricity cables in the vicinity of the said
Property. If there are any earthworks to be carried out in the vicinity
of the cables, the contractors shall engage the services of licensed
cable detection workers to carry out the cable detection work prior
to the commencement of earthworks. All necessary precautionary
measures must be taken to prevent damaging the cables at the
work site. The contractors can contact Earthworks Monitoring &
Cable Protection Section’s Mr Vineesh Viswanathan Nair, Executive
Engineer at Tel: 6470 0668 regarding cable damage preventive
measures. The contractors are required to submit notices to SP
PowerGrid at least 7 days prior to earthworks (including trial
36
trenches) in the vicinity of high voltage electricity cables under the
provisions of the Electricity Act, which came into effect on 1 Jan
2003.
ii. The contractors are advised to acquire a set of drawings for the
electricity cables around the proposed work area. For further details
on cable plan requests, please contact Mr Ismail, Technical Officer
of Earthworks Monitoring & Cabke Protection Section at Tel:
64700660.
iii. For proposed earthworks which are likely to affect the cable and
need cable diversion/protection/suspension etc, after the cable
detection work is done, the contractors can contact the following
officers:
1. Mr Alvin Lim, Executive Engineer of Distribution Network East
Section at Tel: 62409219 on 22kV and below cables.
2. Mr Ng Kwee Leong, Principal Engineer of Regional Network
East 66kV Section at Tel: 64703902 on 66kV cables.
3. Mr Collin Ling Hua King, Principal Engineer of Extra High
Voltage Network Section at Tel: 62909122 on 230kV and
above cables.
The contractors shall notify SP PowerGrid six months before the
commencement of work affecting distribution cables and 24
months if the work involves transmission cables. The cost of cable
diversion/protection/suspension incurred by SP Power Grid shall
be borne by the requesting party.
(e) Urban Redevelopment Authority (URA):
i. Pollutive vehicle repair activities such as panel beating, engine
overhauling and spray painting shall be prohibited.
ii. All other vehicle repair and servicing activities shall be carried out
strictly within the workshop premises, which shall be provided with
the necessary air, water and noise pollution control measures in
accordance to the requirements stipulated in the Code of Practice
on Pollution Control and the Environmental Protection
Management Act and its Regulations.
(f) Civil Aviation Authority of Singapore (CAAS):
i. All fixtures / structures on the rooftop of the development shall
adhere to the height control limit which ranges from 30m AMSL
37
to 35m AMSL.
ii. During construction, all tall construction machineries and
temporary structures must adhere to the same height limits.
(g) Singapore Civil Defence Force (SCDF):
i. The Successful Tenderer and building
owner/management/user are required to comply with the Fire
Safety Act and Regulations, the prevailing “Code of Practice
for Fire Safety Precautions in Buildings” (Fire Code) and the
relevant Codes of Practices and Guidelines.
3.2 The HDB does not warrant or guarantee that the abovementioned
requirements of the various relevant Competent Authorities, authorities,
licensees and persons are exhaustive or current. It is the sole responsibility of
the Successful Tenderer, at its own cost, to check, verify and comply with all
conditions and requirements imposed by the said various Competent
Authorities, authorities, licensees and persons.
38
Annex 1
List of Industries Not allowed in New Water Catchments
(Revised Negative List) Oct 03
S/N Description
1 Bulk storage of toxic and hazardous substances
2 Industries with main activities involving dyeing, bleaching, tanning operations
3 Industries with main activities involving electroplating, galvanizing operations
4 Industries with main activities involving use of organic solvents
5 Industries with main activities involving use of radioactive materials
6 Petroleum refineries
7 Shipbuilding and repairing
8 Slaughtering, preparing and preserving meat
9 Manufacture of drugs and medicines
10 Manufacture of paints, varnishes and lacquers
11 Manufacture of basic industrial chemicals
12 Manufacture of fertilisers, pesticides and herbicides
13 Manufacture of pulp, paper and paperboard
14 Manufacture of soaps and cleaning preparations, perfumes, cosmetics and other toilet preparations
(except those without chemical reactions)
15 Manufacture of synthetic resins, plastic materials and man-made fibres and foams, except those
made of glass
16 Manufacture of miscellaneous products of petroleum and coal
17 Processing of waste oils and waste chemicals
39
S/N Description
18 Processing of food wastes, including composting plant
Notes:
Industries, not classified in the above negative list, are allowed to be sited in the new
catchments subject to the following conditions:
i They are to strictly comply with the pollution control measures as governed by the
Environmental Pollution Control Act and the Sewerage & Drainage Act.
ii All the sewage and sullage are to be discharged to public sewers. Trade effluent
discharges are to strictly comply with the allowable limits under the Trade Effluent
Regulations.
iii All activities are to be strictly confined within enclosed areas and any wastewater
discharges are to be channelled into public sewers. Such activities are not allowed to be
sited within open areas.
iv Enforcement actions by the relevant Competent Authorities eg NEA, JTC, HDB
against the offenders would be stepped up to ensure strict compliance.
20
61
19
17
17
20
1
19
5
15
19
7
3
15
15
17
17
1
EUNOS
UBI
LK
RD
MK23-06321V
MK23-06322P
MK23-06639X
MK23-06643L
MK23-0516
1A
MK23-06312
N
MK23-03652C M
K23-05973
W
MK23-06644C
MK23-06757K
MK23-0
6641N
MK23-06638N
MK23-05922
L
MK23-03654
W
20
1
3
320
10
100
10
10
1
1
320
1
18
3
10
3
320
100
UBI
UBI
RD
RD
3
4
4
MK23-
0483
1L
MK23-
0492
6T
MK2
3-06696
P
MK23-04411N
MK23-06632W
MK23-06633V
MK2
3-06695
V
MK23-03777
T
MK23-04991T
MK23-04992
A
VC
PSTN NOT YET DEMOLISH
FLOW FULLY DIVERTED Dec 07
JALAN TAUGE PUMPING STATION
81.3
0
375
36.14
375
107
600
29.9
0R 450
23.38
600
107.20
450
172.0
912
00
241.9
5
1200
45.6
0
600
67.15
375
45.14600
20
600
TBL98.745
1313826
166628
166629
166565166579
166583
166582
1301992
1882377
1301985
1301988
97.105
103.925
96.288
104.689
96.582
105.034
98.409
106.398
96.087
104.494
94.334
105.851
94.815
105.894
99.007
106.015
97.626
106.374
102.504
104.525
97.035
103.175
245291
245236
245233
1319226
1301989
1301984
245234
1313824
245292
245235
245231
49.80R
150
65.6
0R 150
63.10
R 150
15.2
0R 15
0
124.0
9
R 450
29.10
R 15
0
54.80
R 150
21.10R
150
35.6
5R 150
36.9
0R 150
166563
166562
166561
166557
166555
166564
166560
166556
102.228
104.518102.364
104.416
100.152
104.905
101.316
104.744
100.742
105.072
101.915
104.595
100.605
104.855
100.868
104.878
245224
245217
245226
245218
245219
245222
245225
245223
VC
PSTN NOT YET DEMOLISH
FLOW FULLY DIVERTED Dec 07
JALAN TAUGE PUMPING STATION
81.3
0
375
36.14
375
107
600
29.9
0R 450
23.38
600
107.20
450
172.0
912
00
241.9
5
1200
45.6
0
600
67.15
375
45.14600
20
600
TBL98.745
1313826
166628
166629
166565166579
166583
166582
1301992
1882377
1301985
1301988
97.105
103.925
96.288
104.689
96.582
105.034
98.409
106.398
96.087
104.494
94.334
105.851
94.815
105.894
99.007
106.015
97.626
106.374
102.504
104.525
97.035
103.175
245291
245236
245233
1319226
1301989
1301984
245234
1313824
245292
245235
245231
R
EXISTING SEWER ABANDONED SEWER
SEWER TO BE ABANDONED
NO CONNECTION TO THIS
SEWER IS ALLOWED
EXISTING DRAINLINE
PROPOSED DRAINLINE
EXISTING PUMPING MAIN
PROPOSED PUMPING MAIN
ABANDONED PUMPING MAIN
PUMPING MAIN TO BE ABANDONED
EXISTING SLUDGE MAIN
ABANDONED SLUDGE PUMPING MAIN
LEGEND :
Caution:
The information given is indicative only. The Applicant is advised to verify the information at the site.
THE INFORMATION GIVEN ON THIS SEWERAGE INTERPRETATION PLAN FORMS THE BEST INFORMATION AVAILABLE ON THE DATE PRINTED AND IS LIABLE TO CHANGE WITHOUT NOTICE.
WHILST EVERY ENDEAVOR IS MADE TO ENSURE THAT THE INFORMATION PROVIDED IS CORRECT, THE PUBLIC UTILITIES BOARD DISCLAIMS ANY LIABILITY FOR ANY DAMAGE OR LOSS
THAT MAY BE CAUSED TO ANY PERSON DIRECTLY OR INDIRECTLY AS A RESULT OF ANY ERROR OR OMISSION.
SEWERAGE INTERPRETATION PLAN REHABILITATED SEWER
UNSURVEYED SEWER
Water for All:Conserve,Value,Enjoy
DECOMMISSIONED PUMPING MAIN
UNCOMMISSIONED SEWER
DECOMMISSIONED SEWER
PROPOSED SEWER
Scale 1 : 1500
789456
123456
MANHOLE GIS ID
IMMEDIATE DOWNSTREAM SEWER GIS ID
PROPOSED DTSS TUNNEL
EXISTING DTSS TUNNEL
ANNEX 3
300
150
ABD 300
ABD 300
RW 1200
RW 1200
PROP 1600
200
300
PROP 1600
700
700
200
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EUNOS LINKUBI ROAD 4
Type of Water Mains:
Exis ting Water Mains
Control Valve
Proposed Water MainsWater Mains U nder Construct ionAbandoned Water Mains
PUB Water MainsNEWater Mains
DiaNW - DiaIW - DiaIndustrial Water Mains
RW - DiaRaw Water Mains
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WATER SUPPLY (NETWORK) DEPARTMENTNETWORK DATA AND ASSET MANAGEMENT
1:1,262.69¯
SCALE
THE APPROXIMATE PROPOSED SITE MARKED IN YELLOW
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1. The plan and the information contained herein is privileged and is given solely to the intended recipient for the specific purpose in which the plan is given.No part of the plan shall be reproduced or circulated to others under any circumstances.
2. The information of the watermains on this plan is valid as at date plotted and is given without any liability for any error,mis-statement or omission therein.
3. Position of watermains and the boundary lines of the water catchment indicated on this plan are approximate only. Smaller submains and connections to customers’ premises/properties are not indicated. Trial holes must be carried out to determine the exact alignments and levels of all watermains before commencement of any earthworks.
4. The cost of diversions,if required,of any watermains shall be borne by owner / developer. For watermains of 500mm diameter and above,these are our vital trunk mains and diversions should be avoided unless absolutely necessary. Owner / developer shall determine by means of trial holes the exact alignment and levels of all existing watermains during the design stage and let PUB know whether they are affected by the proposed work so that PUB can advise whether diversion is required. If deem necessary by PUB,the affected watermains shall be diverted and the cost of diversion shall be borne by owner / developer. The cost of diversion shall be finalized upon confirmation on the length of watermains affected.
5. All other necessary precautions must be taken to safeguard and to avoid the damaged to the watermains. The cost of repairs to any watermains damaged as a result of work carried out is to be borne by party which causes the damage. The party will also be billed for the repair of the mains and the estimated quantities of water lost from the damaged mains. The party will also be required to indemnify PUB against all losses and claims arising from damage to watermains.
6. Please inform PUB 24-hour Call Centre at Tel No. 1800-2846600 immediately in the event of damaged to watermain.
ISSUED TO HDBDATE: 22/4/2014DONE BY: KARIMJ
PUB Installat ion
ANNEX 4
40 Scotts Road #14-00 Environment Building Singapore 228231 Website: www.pub.gov.sg
To: Agencies/Developers/Qualified Persons/Contractors
PUB (WRN) ADVISORY NOTE (No. 1 of 2006) (1 Apr 2014)
- PREVENTION OF DAMAGE TO THE SEWERAGE SYSTEM
The sewerage system is a national infrastructure that conveys used water for treatment before it is safely disposed of. The sewerage system thus performs a crucial role in providing us with a healthy and clean environment. If any damage is caused to the sewerage system, environmental pollution may result.
2 The sewerage system includes a network of sewers, pumping mains, the deep tunnel sewerage system (DTSS), and link sewers. To help you protect the sewerage system, we have prepared some guidelines on “Prevention of Damage to The Sewerage System” which can be found in the PUB website at http://www.pub.gov.sg (under General Info-Used Water).
3 In addition, we have attached a list of “Dos and Don’ts” (see Annex 1), some highlights (see Annex 2) of the main requirements from the Code of Practice on Sewerage and Sanitary Works and the General requirements for protection of sewers and pumping mains / Consultation and Submission Requirements (see Annex 3) as easy references to help you prevent damage to the sewerage system.
4 Causing damage to the sewerage system is an offence. We have highlighted, in Annex 4 attached, some Sections of the Sewerage and Drainage Act (SDA), which show the severity of punishment with respect to damage to the sewerage system.
5 For further clarification on :
(i) General Protection Requirement please contact Mr Dave Koh at Tel: 65172208 or Mr Han Yoke Siew at Tel: 65172204 of the Network Management Branch;
(ii) Consultation and Submission requirements please contact Planning Division at 67313656 or 67313352
Issued by:
DIRECTOR WATER RECLAMATION (NETWORK) DEPARTMENT PUB
ANNEX 5
2
Annex 1
DOs AND DON'Ts ON THE PREVENTION OF DAMAGE TO THE SEWERAGE SYSTEM
[Reminder: Under the Sewerage and Drainage Act, the penalty for erecting any building or structure over, across or adjacent to any sewerage system without prior approval from PUB is a fine of up to $20,000. The penalty for causing any damage to sewer is a fine of up to $200,000 or to imprisonment for a term up to 2 years or to both.]
DO
1. Do purchase a Sewerage Interpretation Plan (SIP) from CBPD (NEA).
2. Do obtain approval from PUB, Water Reclamation (Network) Department before you carry out any works including piling works within the Sewer Protection Zone.
3. Do trial holes to identify the exact location of existing sewers/pumping mains/sanitary drainlines /sewer connection lines before any excavation or piling work. Use only manual excavation near the pipes.
4. Do peg/barricade the route along the sewers/pumping mains to forewarn sub-contractors of the presence of sewers/pumping mains, etc.
5. Do consult PUB, Water Reclamation (Network) Department when you are unable to locate existing manholes/chambers/ sewers/pumping mains, etc.
6. Do have proper protection for our existing sewers/pumping mains during excavation. Prior approval must be obtained from Water Reclamation (Network) Department for protection/ diversion works.
7. Do submit a Notification to our Network Management Branch (NMB) (@WaterHub Toh Tuck Complex, 82 Toh Guan Road East #C3-08, Singapore 608576) at least 7 days before commencement of any excavation works near any sewers or sewerage system.
8. Do report to our Network Management Branch (NMB) at Tel: 62894013 should any of our services be damaged, exposed or any sealing work is required for immediate attention.
DON'T
1. Don't excavate, pile or construct any structures in the Sewer Protection Zone without prior approval from PUB, Water Reclamation (Network) Department.
2. Don't allow heavy machinery to move over our existing sewers/pumping mains without adequate protection (e.g steel plate).
3. Don't use excavator for trial holes to locate the existing sewers/pumping mains/sanitary drainlines.
4. Don't lay any services on top of our existing sewers/pumping mains.
5. Don't lay any services inside our manholes/chambers.
6. Don't cover our manholes/chambers with concrete or premix or construction debris during the construction work.
7. Don't place excavated earth on top of our sewers/pumping mains/ manholes/chambers. No overburden load should be imposed on the sewers/pumping mains/manholes/chambers.
8. Don't leave the manhole or inspection chamber cover open. If the cover is damaged in the course of the construction work, replace them immediately or call the Network Management Branch (NMB) at Tel: 62894013 for assistance.
3
Annex 2
Requirements of the code of Practice on Sewerage and Sanitary Works 1. Qualified Persons/Professional Engineers are required to comply with the sewer protection zone
requirements. Sewer Protection zone is defined as the horizontal distance of 25m from the outermost edge of any part of the public sewers (including pumping mains) or 36m from the outmost edge of any part of the DTSS tunnel & facilities within which no works, either permanent or temporary, should be carried out unless the Director, Water Reclamation (Network) Department has given the written permission to do so.
2. Qualified Persons/Contractors working in the vicinity of the sewerage system shall carry out
thorough site investigation to ascertain the exact locations of the sewerage system within and around their project site and mark their locations and plot the information in the proposal drawings.
3. Qualified Persons/Professional Engineers shall consult and make a submission to PUB, Water
Reclamation (Network) Department on any proposed works, either permanent or temporary, within the following sewer protection zones:
(i) 25m for any sewers, and (ii) 36m for Deep Tunnel Sewerage System (DTSS)
He shall ensure that a written clearance from PUB is obtained before commencement of any works within the sewer protection zone.
4. Qualified Persons/Contractors shall consult PUB's Network Management Branch (NMB) (@
WaterHub Toh Tuck Complex, 82 Toh Guan Road East #C3-08, Singapore 608576, Tel: 62894013) when they are unable to locate existing manholes/ chambers/sewers/pumping mains, etc which are indicated on the SIP at the work site.
5. Qualified Persons/Contractors shall submit a Notification to our Network Maintenance Branch
(NMB) at least 7 days before commencement of any excavation works near any sewers or sewerage system.
6. Developer/Contractors to note that for construction sites, sullage water from any shower/bathroom
compartment/wash area shall be discharged into a silt trap before connection to an inspection chamber. This is to prevent the sand/silt from entering the sewerage system.
7. Developers/Contractors shall note that temporary septic tank/sewage treatment plant is not
allowed to serve the temporary work site facilities. In such cases, temporary sewer connection to existing sewer is to be provided.
8. If sewer is not available, Developer/Contractor will have to bring forward the extension of public
sewer to serve the construction site. During the interim, temporary holding tanks (i.e. no discharge to sewer/drain) of sufficient capacity (design flow is 200 liters per person per day and minimum capacity is 2000 liters) for sullage water and portable chemical toilets are to be provided. Licensed Waste Contractor shall empty the temporary holding tanks/chemical toilets regularly.
9. Developers/Contractors shall note that ends of the abandoned sewers/pumping mains shall be
sealed watertight with 225mm thick brick plugs and rendered with cement mortar. The abandoned sewers / pumping mains of 300mm diameter and above on public roads shall be filled with concrete, cement grout or other approved material. All abandoned manholes/chambers are to be demolished and manhole frames and covers removed.
4
Annex 3
GENERAL REQUIREMENTS FOR PROTECTION OF SEWERS AND PUMPING
MAINS
1. Where there are public sewers or pumping mains within your development lot or the sites of your proposed works (eg excavation, soil investigation, piling, tunneling, structure, etc), either permanent or temporary, or if your works are within the sewer protection zone [ie. 25m for sewers and 36m for Deep Tunnel Sewerage System (DTSS)], you are required to obtain a written clearance from the Director, PUB Water Reclamation Network (WRN) before carrying out the works at the site. Please click here for the application form.
2. Work carried within the development lot shall take into consideration the sewer setback distance
and sewer protection zone. 3. No structure either permanent or temporary shall be erected over or within the below minimum
sewer setback distance from the public sewers or pumping mains. The requirements on the sewer setback distance is stipulated in the Code of Practice on Sewerage and Sanitary Works and the below minimum clearance distances can also be found at: http://www.pub.gov.sg/general/usedwater/SewerageandSanitaryWorks/Pages/SewerProtectionZ
one.aspx
SEWER SETBACK DISTANCE CLEARANCE REQUIRED
Sewer Pipe
Diameter (mm) Nett Clearance Required
150 to 600
(depth ≤ 3m)
1.0m from outer edge of any structure to centreline of sewer
pipe
150 to 600
(depth > 3m to 5m)
1.5m from outer edge of any structure to centreline of sewer
pipe
150 to 600
(depth > 5m)
2.0m from outer edge of any structure to centreline of sewer
pipe
> 600 to 1500
2.5m from outer edge of any structure to outer edge of sewer
bedding
> 1500 to 2500
3.0m from outer edge of any structure to outer edge of sewer
bedding
> 2500
4.0m from outer edge of any structure to outer edge of sewer
bedding
DTSS Tunnel &
Facilities
6.0m from outer edge of any structure to outer edge of tunnel
or structure
PUMPING MAIN SETBACK DISTANCE CLEARANCE REQUIRED
Pumping Main
Diameter (mm) Nett Clearance Required
100 to 600
(depth ≤ 3m)
1.0m from outer edge of any structure to centreline of the pipe
100 to 600
(depth > 3m to 5m)
1.5m from outer edge of any structure to centreline of the pipe
5
100 to 600
(depth > 5m)
2.0m from outer edge of any structure to centreline of the pipe
> 600 to 1500
2.5m from outer edge of any structure to outer edge of the pipe
> 1500 3.0m from outer edge of any structure to outer edge of the pipe
4. No utilities services (cable, gas pipe, water pipes, etc) either permanent or temporary shall over-
cross / under-cross within one metre (1m) from the outer edge of sewers or pumping mains. For
those utilities services that over-cross / under-cross with a vertical clearance of less than one
metre to any sewer, you are required to obtain a written clearance from the Director, PUB
(WRN) before carrying out any works at the site. In addition, pre- and post-construction CCTV
inspection shall be carried out on the affected sewer(s) and manholes. The CCTV reports and
video shall be submitted to PUB (WRN) Department. From 1 Jan 2013, PUB only accept CCTV
inspection and reports from PUB Registered CCTV contractors. The list of latest PUB registered
CCTV contractors is available in our website,
http://www.pub.gov.sg/general/usedwater/Documents/RegisteredCCTVContractor.pdf
5. A thorough site investigation shall be carried out to determine the exact position and levels of the
existing sewers / pumping mains before commencement of works. QP shall refer to PUB’s advisory on 'Prevention of Damage to the Sewerage System' which can be viewed at: http://www.pub.gov.sg/general/Pages/PreventionofDamage.aspx#Prevention for measures to prevent damage to sewerage systems.
6. All necessary precautions and protection measures shall be taken to safeguard the sewers or pumping mains during construction works. The cost of repairs to any sewers / pumping mains damaged as a result of work carried out shall be borne by the party who causes the damage. PUB’s approval shall be obtained before carrying out any diversion of existing sewers / pumping mains. The cost of diverting any existing sewers / pumping mains shall be borne by the party necessitating the diversion works.
7. The construction works or activities shall not cover up/bury any sewer manholes or valve chambers and appurtenances for pumping mains.
8. The public sewers and pumping mains must be accessible for maintenance and repair works at all times.
9. Any work carried out in the vicinity of existing sewers or pumping mains shall not subject the sewers or pumping mains to a vibration of more than 15mm/s peak particle velocity at any frequency.
10. QP shall supervise the works and in accordance with PUB’s advisory on “Prevention of Damage to the Sewerage System”, plans / drawings submitted and approved by PUB (WRN) and Clearance Certificates issued by CBPD (NEA).
11. No deviation from the plans approved by PUB or CBPD (NEA) shall be made unless with prior written approval from PUB (WRN) or CBPD (NEA).
12. Copies of all PUB or CBPD’s approvals including approved plans shall at all times be kept at the site and made available for audit check by PUB staff when required.
13. QP shall comply with the submission and monitoring requirements pertaining to the protection of public sewers as given in Appendix 1. If the proposed works are close to larger sewer(s) (≥
6
900mm in diameter) or DTSS tunnel/structures, the QP shall also comply with the additional protection requirements given in Appendix 2.
14. Where works need to be carried out in public sewers or manholes, QP shall submit to PUB, (WRN), Network Management Branch, an application (Form B) to work in the public sewerage system through CORENET e-submission.
15. Web-based IP surveillance cameras shall be provided to continuously monitor the construction
activities in the vicinity of the DTSS tunnel/structures and large diameter (> 900mm) sewers. The number of cameras to be provided shall be approved by PUB and shall be sufficient to cover at least the sewer setback distances of the DTSS tunnel/structures and large diameter sewers.
16. Please call PUB’s Network Management Branch (NMB) at Telephone No. 62894013 or PUB-ONE hotline at 1800-2846600 / Fax at 63820692 immediately should any of the public sewers or pumping mains be damaged or exposed.
7
Appendix 1
CONSULTATION AND SUBMISSION REQUIREMENTS
1. Consultation and Submission
Where there are public sewers or pumping mains within your development lot or the sites of your
proposed works (eg excavation, soil investigation, piling, tunneling, structure, etc), either
permanent or temporary, or if your works are within the sewer protection zone [ie. 25m for sewers
and 36m for Deep Tunnel Sewerage System (DTSS)], you are required to obtain a written
clearance from the Director, PUB (WRN) before carrying out any temporary works/piling
works/building works at the site. Please note the documents that need to be submitted as
stipulated in the application form.
Please also note the following: (a) you need to get the Development Control (DC) plan and BP Plan / detailed plan sewerage
plan approved by CBPD (NEA) prior to seeking written clearance from Director, PUB (WRN). (b) If a diversion is proposed for the existing sewer, proposal for the diversion sewer shall have to
be approved by PUB. Then, the diversion sewer shall first be completed and passed for operation by PUB before any work is allowed to start on the diversion of the existing sewer.
(c) For works within the DTSS and/or large diameter sewers (≥ 900mm in diameter) protection
zone (25m for sewers and 36m for DTSS); QP shall submit the following additional documents
to PUB (WRN) to obtain the written clearance.
(i) Detailed Plans of development or engineering works and survey plan indicating the alignment of the sewers in relation to the works;
(ii) Construction Impact Assessment Report (CIAR). Please refer to Appendix 2 item 11 for details on the report.
(d) QP shall submit a Notification to PUB’s (Network Management Branch) Fax 63820692 at
least 7 days before commencement of any excavation / tunneling / piling / soil investigation /
temporary works near any sewers or sewerage system.
(e) A pre-construction CCTV inspection report together with the CCTV video (DVD) shall be
submitted if any sewer is within or adjacent to the development lot. From 1 Jan 2013, PUB only
accept CCTV inspection and reports from PUB Registered CCTV contractors. The list of latest
PUB registered CCTV contractors is available in our website,
http://www.pub.gov.sg/general/usedwater/Documents/RegisteredCCTVContractor.pdf. (f) For small redevelopment/A&A works of single landed property (terrace, semi-detached and
detached house), the submission of pre-construction CCTV survey report is waived and QP is
only required to submit the post-construction CCTV survey report upon completion of the
development work.
2. Monitoring and Submissions Required during Construction Stage
Where there is any public sewer(s) or pumping main(s) within and/or adjacent to the development
lot, QP shall comply with the following general requirements and ensure that copies of all PUB’s
8
approvals, including approved plans, shall at all times be kept at the site and made available for
audit check by PUB when requested.
Before Commencement of Works
(i) Registered Surveyor to verify, set out and carry out the pegging of the sewer alignment, tunnel/pipe jacking alignment, pile/drilling hole positions, temporary earth retaining system (TERS) alignment on site and endorse on setting out plan.
(ii) QP shall verify and check that the setting out plan is as per DC/BP/Detailed plan submissions.
(iii) QP shall check the positions of all heavy construction machinery and lifting equipment and material storage area in the vicinity of the sewer and ascertain that the imposed loads will not cause any damage to the sewer.
(iv) If the proposed work is likely to affect the existing sewers, the QP shall install a level sensor at the nearest manhole upstream of the affected sewer section. The level sensor shall be provided with data logger and auto alarm system at preset trigger levels. When the preset level is triggered, the alarm system should be capable of informing PUB via SMS. Details of the trigger levels and PUB staff to receive the SMS will be conveyed to the QP when the system is installed.
(v) The QP shall provide contingency plan to ensure that the flow is not disrupted should the existing sewer be damaged during construction works. QP shall ensure that the contingency plan is activated and repair works to the damaged sewer are immediately carried out in the event that any sewer is damaged due to the works.
During Implementation of Works (for sewers)
(vi) QP/QP’s competent site representative shall closely monitor the works and provide standing supervision and conduct verticality and penetration depth checks on the piles, TERS and excavation works to ensure that they are installed within the allowable construction tolerance limits in terms of setting out, eccentricity and verticality. Records of the standing supervision, verticality and penetration depth checks, as-built piling, and TERS drawings shall be properly maintained on-site and made available for inspection upon request.
3. Submission upon Completion of the Development
Where there are public sewers or pumping mains within and /or adjacent to your development lot,
upon completion of the development, QP shall submit:
(i) the “as-built” survey plan endorsed by a registered surveyor to show the exact location/clearances (horizontal/vertical) between the existing sewer(s)/manhole(s) and all the existing/new buildings/structures including wall, drains, boundary lines, etc. The top and invert levels of all the sewer manholes shall be indicated in the plan. The QP shall:
highlight and certify if there are any changes in the condition of the existing sewer(s) / manhole(s) between the post and the pre-construction survey plan.
confirm that the minimum clearance distance between the building/structure and the sewer met the stipulated requirements in the code of practice and is in accordance with the requirements/conditions imposed by PUB(WRN) when the development plans were approved.
certify with submission of the as-built drawing of the installed piles/drilling boreholes that there are no impacts/damages caused to the sewers, manholes and pumping mains
9
based on the as-constructed works, instrumentation monitoring results, sewer pre/post construction CCTV survey report and pre/post level construction condition survey report submitted to PUB.
(ii) A post-construction CCTV report together with the CCTV video (DVD) for new / existing sewer(s) and manholes within or adjacent to the development site. From 1 Jan 2013, PUB only accepts CCTV inspection and reports from PUB Registered CCTV contractors. The list of latest PUB registered CCTV contractors is available in our website, http://www.pub.gov.sg/general/usedwater/Documents/RegisteredCCTVContractor.pdf.
10
Appendix 2
ADDITIONAL REQUIREMENTS TO PROTECT EXISTING LARGE DIAMETER SEWERS (≥900mm
IN DIAMETER) / AND DTSS TUNNELS & STRUCTURES
General
1. Before commencing any works in the vicinity of sewers, pumping mains and DTSS structures (i.e. DTSS tunnels, shafts and ancillary structures); the QP shall verify the exact locations of the sewers, pumping mains and DTSS structures.
2. The QP shall design both the temporary and permanent works in such a way to ensure that ground movements are kept to an absolute minimum. The employment of proven techniques and good workmanship are important to minimize ground loss and in turn ground movements.
3. The QP shall select and ensure the operation of construction equipment shall be in a manner such that vibration induced damage to the sewers and DTSS structures is prevented.
4. The QP shall be fully liable for any repair of the sewers, pumping mains and DTSS structures damaged by the construction works. He shall also carry out any precautionary, protective or recovery measures deemed fit by PUB or as conveyed to him during the construction or the defects liability period of the works.
Construction within the Sewer and DTSS Setback Distances (see Annex 3, item 3)
5. The QP shall establish and inform PUB of the procedures and methods for all excavation and other construction works within the sewers and DTSS setback distances to prevent damage to the sewers and DTSS structures during the work.
6. If the proposed works involve the installation of piles or structure or excavation to a level within 3m of the DTSS tunnel, pre-probing shall be conducted to ascertain if the DTSS tunnel is in the way of the works. Before commencement of works, the QP shall submit the detailed method statement and drawings for the pre-probing works, details of the machinery/equipment used (especially that for the advancement of the probe) with analyses / assessment to demonstrate that the pre-probing method proposed is non-invasive and will not cause any impact or damage to the DTSS tunnel.
7. Equipment Vibrations - Construction activities such as piling, excavation, soil improvement, diaphragm wall and retaining wall construction etc and the use of construction equipment such as piling/boring machine etc shall not subject the sewers and DTSS tunnels to a peak particle velocity (PPV) exceeding 15 mm/s at any frequency. The QP shall provide a detailed impact assessment that clearly demonstrates the vibration attenuation for each of the equipment proposed to be used at the development site and in similar ground conditions to show that this vibration limit would not be exceeded on the existing sewers and DTSS tunnels. On-site testing and monitoring with a seismometer may be requested by PUB to verify the QP’s assessment.
8. Ground Displacements - Ground displacements caused by construction or other activities shall be “zero”. If the QP's analysis shows that the ground displacement due to the construction or other activities exceeds “zero”, a further design check shall be undertaken to ensure that the construction or other activities will not induce a calculated crack width of 0.1mm in the DTSS concrete structure.
9. Load Transfer from Foundations to sewers and DTSS Tunnel - Load transfer (if any) from the foundation elements to the sewers and DTSS tunnels (e.g. by skin friction) shall not exceed an average of 10 kPa (10 kN/m
2). This requirement may necessitate the “debonding” of the entire
foundation elements above the sewers and DTSS tunnel levels.
11
10. Groundwater Drawdown - The groundwater drawdown shall not exceed 10 kPa in the vicinity of the sewers and DTSS tunnels.
Assessment of Construction Effects on Existing Structures
11. Construction Impact Assessment Report (CIAR) - The QP shall carry out a construction impact assessment of the construction effects of the works on the sewers and DTSS structures in the vicinity of the works and submit the report to PUB for approval. The report shall include the following details:
(i) The ground conditions, geotechnical profiles and relevant borehole logs.
(ii) The proposed construction equipment and methods, and sequencing of construction.
(iii) Assessments on the use of the proposed construction equipment /methodology on the existing sewers/DTSS tunnels, vibrations, ground displacements, load transfer from foundation elements to the sewers and DTSS tunnels and groundwater draw downs and how the impacts would be mitigated to meet requirements.
(iv) Vibration characteristics and attenuation for major construction equipment/methodology.
(v) Instrumentation and monitoring proposals.
(vi) The damage potential and risks to the sewers and DTSS structures.
(vii) Preventative and precautionary measures to protect the sewers and DTSS structures from damage and remedial measures to be taken in the event of damage/incidents.
12. The QP shall advise PUB on the assessed probable risk and level of damage to the sewers and DTSS structures and his proposed mitigating measures for preventing the sewers and DTSS structures from damage to the satisfaction of PUB.
Instrumentation and Monitoring Programme
13. The QP shall carry out an instrumentation and monitoring programme to monitor the surface and subsurface ground movements, vibrations, the variation of ground water table and pore pressures, and the displacement and distortion of sewers and DTSS structures, and assess the effect of construction works on the sewers and DTSS structures in the vicinity.
14. The QP shall include in the monitoring plan all sewers and DTSS structures that in his view are
likely to be affected by the works. 15. The QP shall submit full details of the proposed monitoring procedures and instrumentation to
PUB for concurrence before commencing the works. 16. The QP’s method statement shall include the proposed monitoring intervals and all requirements
imposed by PUB.
17. The QP shall commence the monitoring programme as soon as possible and several months before the construction work is scheduled to start. This is crucial for capturing the on-going rate of intrinsic settlement, subsurface ground movement, background vibration levels, etc. at the site so that it would be possible to differentiate them from those induced by the works later.
18. The QP shall be responsible for ascertaining and setting the safe limits of ground movements,
vibration levels or other changes for ensuring the structural integrity and proper functioning of all sewers and DTSS structures. He shall provide comprehensive basis for the proposed safe limits.
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19. The QP shall verify and certify by monitoring that construction works have not resulted in displacements or vibration levels that have or will cause damage to any sewers or DTSS structures. As a minimum, the following are required to be carried out and the relevant details are to be submitted to PUB: (i) Monitoring of the displacements or vibration levels of sewers and DTSS structures or the
adjacent ground from the construction works
(ii) Preparation of action plans for remedial action in the event that displacements or vibration levels exceed the design limitations or cause damage.
20. It shall be clearly understood that the submissions of the instrumentation monitoring results and reports to PUB are only for PUB’s information. The QP shall be fully responsible for the analysis and interpretation of all the readings and measurements and for taking all remedial measures where necessary. When abnormal readings or measurements are obtained, QP shall immediately investigate the causes of the abnormalities and take all necessary remedial measures. QP shall promptly inform PUB should such abnormalities be likely to affect the structural integrity of the sewers, pumping mains and structures.
21. All deformation monitoring instrumentation shall be designed to allow for any ground settlements, heaves or deformations that may occur. A new set of instrumentation shall be provided or resetting of the instrumentation shall be carried out, as recommended by the manufacturer, if the instrumentation reading exceeds 85% of its design value.
22. Instrumentation monitoring regime consists of inclinometers, ground settlement markers, vibration meters, piezometers, strain gauges, rod extensometers, etc. shall be carried out by QP to check whether ground movements & vibration impacts are within allowable limits during the construction works. Records of the instrumentation monitoring regime shall be endorsed by the QP and properly maintained at the site, submitted to PUB or made available for inspection by PUB upon request.
23. QP shall monitor and review the instrumentation monitoring results daily, looking out particularly for excessive ground movements that may cause damage to the sewer. The QP shall submit the instrumentation monitoring records to PUB (NMB) at a frequency stipulated by PUB. QP shall highlight in his submission if there are any excessive ground movements monitored or any other abnormalities.
24. QP shall stop the works immediately if the instrumentation monitoring results exceed the allowable limits and inform PUB (NMB) immediately before investigating whether the works have any impacts on the sewers. The QP shall submit his assessment of the impacts of the works on the sewer, including his proposed mitigating measures to address the excessive ground movement or any other abnormalities, to PUB for approval, before resuming the works.
Surveillance Cameras above Large Diameter Sewers (≥900mm in Diameter) & DTSS Tunnel/Structures
25. Contractor shall provide web-based IP surveillance cameras to continuously monitor construction activities in the vicinity of the DTSS tunnel/structures and large diameter (> 900mm) sewers. The number of cameras to be provided shall be approved by PUB and shall be sufficient to cover at least the setback distances of the DTSS tunnel/structures (ie. 6m from both edges) and large diameter sewers (ie. 2.5m for 900mm to 1500mm diameter; 3m for >1500mm to 2500mm diameter and 4m for >2500mm diameter, from both edges).
26. The surveillance cameras must be able to capture still pictures and perform continuous video recording.
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27. The contractor shall provide PUB with the Internet website address for centralized viewing of the still picture and video recordings of the construction activities above DTSS tunnel/structures and large diameter sewers captured by the surveillance cameras.
Pre and Post-Construction CCTV, Laser and Sonar Inspection for DTSS Tunnel for
Construction Works carried out within DTSS 6m Setback Distance
28. A pre and post-construction CCTV, sonar and Laser inspection for the DTSS tunnel, to be carried out by a specialist contractor with proven track records for deep tunnel inspections, may be required for construction works carried out within the DTSS 6m setback distance.
29. The specialist contractor’s inspection system for the DTSS tunnel shall comprise CCTV, laser and sonar inspection technologies for a complete assessment of the condition of the DTSS tunnel. The proposed inspection system shall have proven track records for carrying out similar inspections of large diameter deep sewer tunnels.
30. The QP shall submit the pre-construction CCTV, Laser and Sonar inspection report (highlight all minor and major geometric defects) and records (in DVD) of the DTSS tunnel prepared by the specialist contractor prior to the commencement of works within the DTSS 6m setback distance.
31. For every pre- and post-construction CCTV inspection carried out, the QP shall compare the two inspection reports and highlight / certify whether there is any deterioration in the tunnel condition. QP shall promptly inform PUB WRN should any abnormalities be found that may have affected the structural integrity of the DTSS. CCTV reports together with the CCTV video shall be in accordance with PUB (WRN)’s CCTV requirements.
32. The QP would have to apply to PUB for a permit to access the DTSS Shafts to carry out the DTSS tunnel inspection. His application for permit shall include the proposal for the implementation of the DTSS tunnel inspection. The proposal shall include a Risk Assessment Report, deployment procedures & methodology, format/details of analytical reports with details of the inspection system used, the CVs of competent personnel with track record of similar inspections, safety plans and odour control system.
33. The QP/QP's representative (RE/RTO) and safety officer must provide standing supervision while the access shaft is opened and during the DTSS tunnel inspection to ensure that no damage is caused to the DTSS tunnel and safety of the contractors or any personnel and public is not compromised.
34. The QP/QP's representative (RE/RTO) shall ensure that adequate ventilation and lighting are provided to ensure sufficient brightness and clear views for inspection and that details of the tunnel are not obscured by gases in the tunnel. Ventilation should not lead to public health concerns and sufficient odour control systems must be provided.
35. During the inspection, the QP/QP's representative (RE/RTO), in consultation with the safety officer, shall ensure that all necessary/adequate measures are taken to safeguard the safety of the contractors’ personnel and public. The measures shall include risk assessment, confined space entry safety requirements, prevent access by public to the access shaft while the access shaft is opened, securing of contractors’ personnel to the secured scaffolding members (metal based) (which can take human weight as a minimum) when near opened shaft and confirmation that access shaft covers opened for inspection are tightly closed and secured with bolts at the end of the inspection. Risk Assessments should include “Hazop” to ensure all measures necessary to prevent damage to the tunnel and shaft are adopted during the inspection.
36. During the inspection process, the QP shall ensure that all precautionary actions are taken to prevent damage to the DTSS tunnel and shafts. The precautionary actions shall include but not limited to the following:
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During the deployment and retrieval of the inspection system into and out of the DTSS shaft
(i) Measures must be in place to prevent excessive swaying during the deployment and retrieval of the inspection system into and out of the DTSS shaft to prevent damage to the shaft. Adequate padding shall also be provided at appropriate locations on the inspection platform to prevent damage to the DTSS shaft's internal lining.
(ii) Pan-Tilt and Zoom (PTZ) CCTV camera that can rotate 180 degrees shall be mounted on the inspection system and used to view backward and forward during the deployment and retrieval to ensure that the inspection platform maintains a safe distance from the access shaft wall and does not cause any damage to the shaft.
During the inspection of the DTSS tunnel
(iii) The Contractor shall examine carefully the shaft and tunnel interior for areas that might be susceptible to scratching by the tether or the inspection instrument and take additional measures/care to prevent any potential damage to the protective liner covering the shaft and tunnel interior or structural components of the DTSS. Adequate protection such as the use of “Tiger Tails” shall be provided to prevent damage to the DTSS tunnel/shaft.
(iv) An example on the deployment of "Tiger Tails" to protect the tether from scrapping against the shaft or tunnel is shown in Figure 1 below.
(v) Upon the completion of the inspection of the tunnel, QP shall ensure that the inspection platform re-inspect in the reverse direction using the Pan-Tilt and Zoom (PTZ) CCTV camera system to check and ensure that the DTSS tunnel was not damaged in any way due to the inspection.
FIGURE 1 – PLAN & ELEVATION VIEW SHOWING DEPLOYMENT OF “TIGER TAILS” TO PROTECT DTSS
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Annex 4 Sewerage and Drainage Act (chapter 294)
SDA Section
Description of Section
Description of Section Penalty
13A(1)
Duty to enquire before excavation No person shall dig, bore, trench, grade, excavate, tunnel or break any ground with any mechanical equipment, tool or explosive, or allows his employee or agent to do so, without first – a) obtaining from the Board the relevant drainage plan or sewerage plan or other plans or records to ascertain the location of any public sewerage system or part thereof that may be interfered with by such works; b) carrying out trial trenches to physically ascertain the location of any such public sewerage system or part thereof that may be interfered with by such works; and c) complying with such other requirements as the Board may specify to protect any such public sewerage system or part thereof within the vicinity of such works,
Any person found guilty shall be liable on conviction to a fine not exceeding $50,000 or to imprisonment for a term not exceeding 3 years or to both.
14(1)
Works likely to affect sewer or sewerage system not to be carried out without Board’s certificate or approval No person shall – a) erect or cause or permit to be erected any object, building or structure over, across or adjacent to any sewer or sewerage system; or b) carry out or cause to be carried out any other works which adversely affect or are likely to adversely affect any sewer or sewerage system, directly or indirectly without obtaining, in respect of those works, a clearance certificate or the approval of the Board
Any person found guilty shall be liable on conviction to a fine not exceeding $20,000.
18(1)
Discharge of sewage, etc.
No person shall, without the written approval of the Board, discharges or causes or permits the discharge of any sewage, waste matter or effluent into any public sewerage system or any drain-line or sewer communicating with a public sewerage system – a) directly or indirectly, from any conveyance or mobile toilet; or b) by opening a manhole or an inspection chamber or any other means of access to the public sewerage system,
Any person found guilty shall be liable on conviction to a fine not exceeding $20,000
19(1)
Restrictions on use of public sewerage system No person shall throw, empty or pass, or suffer or permit to be thrown or emptied or passed, into any public sewer, or into any drain-line or sewer communicating
Any person found guilty shall be liable on conviction to a fine not exceeding $20,000.
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with a public sewer – a) any matter or other substance likely to injure the sewer or drain-line, to interfere with the free flow of its contents or to affect prejudicially the treatment and disposal of its contents; or b) any sand, earth, gravel, cement, cement grout, brick, timber, wood or other building materials.
20(1)
Damage caused to public sewer, etc. No person shall – a) cause any damage to any public sewer or any drain-line or sewer communicating with a public sewer; or b) renders any public sewer or private sewer a nuisance.
Any person found guilty shall be liable on conviction to a fine not exceeding $40,000 or to imprisonment for a term not exceeding 3 months or to both
20(2)
Damage caused to public sewer, etc. No person shall – a) do any act which renders any public sewer or private sewer dangerous or injurious to health; b) cause any damage to a pipe of 0.9 metres or greater in diameter that is part of or connected to the public sewerage system; or c) do any act which disrupts the operation of or causes damage to any sewage treatment plant, sewage treatment works or water reclamation facility.
Any person found guilty shall be liaible on conviction to a fine not exceeding $200,000 or to imprisonment for a term not exceeding 2 years or to both.
63(b) No person shall fail to comply with any condition subject to which any clearance certificate is issued or approval is granted by the Board under section 33,
Any person found guilty shall be liable on conviction to a fine not exceeding $15,000 or to imprisonment for a term not exceeding 3 months or to both, and in the case of a continuing offence, to a further fine not exceeding $500 for every day or part thereof during which the offence continues after conviction.