WORK METHOD STATEMENT
Tittle : Method Statement for Sewerage Work
Project : Pembinaan Sekolah Baharu 30 Bilik Darjah Dan Lain-lai Kemudahan Di
Sekolah Kebangsaan Permai, Kemaman, Terengganu
1. OBJECTIVE
This work method statement covers the sewerage reticulation works for Pembinaan
Sekolah Baharu 30 Bilik Darjah dan Lain-lain Kemudahan Di Sekolah Menengah
Kebangsaan Permai, Kemaman, Terengganu.
2. SCOPE
In general scope of work for this work method statement cover the following:
Scope Of Works Descriptions / Details
Sewerage Reticulation Work This works consist of the following items :
• Survey and setting out
• Excavation trench
• Lay and join pipes
• Construction of manhole
• Backfilling
• Testing
3. RESOURCE PLANNING
3.1 Machineries
Item Description
1 Excavator
2 Backhoe
3 Dump truck
4 Plate Compactor
5 Excavator
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WORK METHOD STATEMENT
Tittle : Method Statement for Sewerage Work
Project : Pembinaan Sekolah Baharu 30 Bilik Darjah Dan Lain-lai Kemudahan Di
Sekolah Kebangsaan Permai, Kemaman, Terengganu
3.2 Manpower
Item Description
1 Surveyor
2 Supervisor
3 Skilled workers
4 General workers
5 Machine operator
3.3 Materials
Item Description
1 HDPE pipe and fittings & joints
2 Pre Cast manhole
3 Concrete grade 20
4 BRC
5 Aggregate
4.0 MATERIAL HANDLING & DELIVERY INSPECTION
4.1 Material Handling
4.1.1 In general, all construction materials shall be planned and delivered near to
the workplace to avoid double handling.
4.1.2 Correct or suitable machine shall be used during loading and unloading the
materials.
4.1.3 Reinforcement bars or BRC shall be stacked higher minimum 300mm from
ground to avoid excessive corrosion.
4.1.4 The pipes shall be placed in the designated area in the good condition and care
must be taken when handling the materials.
4.2 Material Delivery Inspection
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WORK METHOD STATEMENT
Tittle : Method Statement for Sewerage Work
Project : Pembinaan Sekolah Baharu 30 Bilik Darjah Dan Lain-lai Kemudahan Di
Sekolah Kebangsaan Permai, Kemaman, Terengganu
Material Items to be Checked or Inspected Method Of
Inspection
Aggregate Aggregate shall be cleaned free from Visual
unwanted material such as rubbish,
logs, peat, lumps.
BRC Rusted or excessive peel off material Visual & Measure
shall be rejected immediately, size &
quantity as per construction drawing.
HDPE Pipe • Material delivered at site shall be in Visual
& RC good condition or not damaged.
Manhole • Material delivered to site shall be as
per construction drawing.
5.0 WORK METHODOLOGY
5.1 Survey, Setting Out And Excavation of Trench
5.1.1 Before commencing any excavation, the Contractor shall take cross
sections or levels along the proposed line of excavation at frequent
intervals. This cross section or level shall be inspected with the
Consultant.
5.1.2 The alignment of the sewer pipe will be established and marked with
timber pegs. Reference or benchmark pegs will also installed two
meters to the left or right side of the excavation line (away from
working side).
5.1.3 All excavation shall be carried out to the required lengths, breadths,
depths, and curvatures as may be necessary for the Construction of the
works or shown in the drawing.
5.1.4 The trench shall be of such width as indicated in the drawings so as to
allow adequate working space for the pipe jointers and the width of
trenches at surface shall be the same unless otherwise directed.
5.1.5 The trench to lay the sewer pipe will be excavated with an excavator
or backhoe so that it can excavate the trench properly to depth and
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WORK METHOD STATEMENT
Tittle : Method Statement for Sewerage Work
Project : Pembinaan Sekolah Baharu 30 Bilik Darjah Dan Lain-lai Kemudahan Di
Sekolah Kebangsaan Permai, Kemaman, Terengganu
widths and lift the pipes into position and be able to push the spigot
into the socket.
5.1.6 All excavated material shall be deposited so that it possible do as little
damage and inconvenience as possible.
5.1.7 The excavation shall proceed in such portions as E.R. may direct and
no placing of bedding or permanent work of any kind to commence
until E.R has approved of the excavation.
5.1.8 The excavation will be kept free from water by starting the excavation
from the downstream end and working uphill and by any necessary
pumping or bailing out.
5.2 Sewer Pipe Laying And Installation
5.2.1 After inspection of the trench formation, the pipe bedding material
will be laid to a minimum thickness as shown on the drawing and
compacted with a plate compactor.
5.2.2 All hdpe pipes and specials should be from approved manufacturer.
No defective pipes and fittings should be used in this project. All
fittings and joints to be jointed should follow the manufacturer’s
specification.
5.2.3 The second and subsequent pipes will have the spigot end with the
sealing ring fixed at the correct position and pushed home into the
socket. Temporary support will be used to prevent lateral movement at
this operation.
5.2.4 This will be continuing until the next manhole position is reached and
the process will start again on the next sewer pipe run.
5.2.5 Pipe shall be laid to straight lines and even gradient as required.
5.2.6 All pipes shall be kept free from earth, debris, superfluous cement and
other obstruction during laying until the completion of the works.
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WORK METHOD STATEMENT
Tittle : Method Statement for Sewerage Work
Project : Pembinaan Sekolah Baharu 30 Bilik Darjah Dan Lain-lai Kemudahan Di
Sekolah Kebangsaan Permai, Kemaman, Terengganu
5.2.7 When the alignment of the sewer pipe is confirmed, the remaining
crusher run bed/haunch shall be completed ensuring that the bottom of
the pipe is fully supported.
5.2.8 The bedding and haunching of pipes shall be done as shown in the
drawing or directed by E.R.
5.3 Precast Manhole
5.3.1 All precast manhole shall be constructed in accordance with the
drawings complying with B.S 5977 or other approved equivalent. All
dimensions and depth shall be as specified. All work done should be
under the supervision of the E.R or his representatives.
5.3.2 At each change of gradient or direction, at each intersection with other
sewers and at such other points as shown on the Drawings or as
directed by the E.R, a manhole shall be constructed to the form and to
the dimension shown on the drawing and as directed by the E.R.
5.3.3 The bases of all manholes are to be formed of concrete and the
thickness as shown on the drawings.
5.3.4 Channel inverts shall be accurately laid to meet pipe invert elevations
at the same time as the sewer pipes are laid.
5.3.5 Manholes floor shall be constructed with concrete formed to the
required shape, bends, tapers, junctions and double junctions.
5.3.6 The pipes shall be laid at the levels, slopes, and in the directions
instructed by the E.R.
5.3.7 The manhole cover shall be laid with their frames bedded on the
precast manhole. Manhole covers generally shall be set to the road
profile and be flush with the road surface.
5.3.8 Manhole covers located in unimproved areas shall be set at an
elevation to prevent the entry of surface water as directed by E.R.
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WORK METHOD STATEMENT
Tittle : Method Statement for Sewerage Work
Project : Pembinaan Sekolah Baharu 30 Bilik Darjah Dan Lain-lai Kemudahan Di
Sekolah Kebangsaan Permai, Kemaman, Terengganu
5.3.9 All manholes shall be watertight on completion and where leakage is
discovered the Contractor shall perform such work and provide all
materials as are necessary to render such faulty work watertight.
5.4 Backfilling and Compaction
5.4.1 In backfilling excavations after permanent works therein have been
approved by E.R., the best and most suitable materials shall be used.
5.4.2 Where excavated materials are not considered suitable by E.R.,
selected materials from approved sources shall be used for backfilling
and bedding.
5.4.3 Where necessary, the Contractor shall adjust the moisture content of
the refill material either drying out or by adding water to assist the
compaction of the material.
5.5 Testing and Commissioning
5.5.1 CCTV Inspection
The following subsections outline details on how the CCTV
inspection requirements shall be implemented. These guidelines are
also aim to enhance professionalism in line with progress in sewerage
field, and promote efficiency and cost effectiveness as well as
transparency and accountability in sewerage system development.
Technical Requirements and References
i. Analysis of defects shall be based on WRc Manual for Sewer
Condition Classification Latest Edition.
ii. Equipment and test devices to be used are as listed in Section 4.10.3.
iii. For sewer with diameter larger than 1050 mm, man-entry CCTV
survey mode may be adopted unless it can be demonstrated that
Volume 3 Sewer Testing Malaysian Sewerage Industry Guidelines
108 the CCTV can be maintained in a stable position on or near the
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WORK METHOD STATEMENT
Tittle : Method Statement for Sewerage Work
Project : Pembinaan Sekolah Baharu 30 Bilik Darjah Dan Lain-lai Kemudahan Di
Sekolah Kebangsaan Permai, Kemaman, Terengganu
central axis of the sewer and images captured are satisfactory and not
distorted.
Specifications for CCTV unit’s equipment
i. Solid state colour CCTV camera with pan & rotate features, together
with a lighting unit, automatic date/ meter age.
ii. A self-powered tractor or crawler on which the camera is conveyed
along a pipeline under inspection in a stable manner.
iii. Calibration chart for various sizes of sewer for the camera used.
iv. Test device for the monitor and video recorder to establish the
effectiveness and accuracy of the ‘on-site’ monitor and video recorder.
v. The control unit comprises the camera unit, crawler control and
screenwriter. This console can be mounted permanently in a vehicle or
use as portable system.
vi. A video recorder for recording high quality video images.
vii. A mean of producing still images from the monitor screen.
viii. A PC-based site reporting system capable of producing reports
customized to the Contractor’s needs and to include photographs
captured directly from video.
In the events of any blockages, damages, seepages and etc. to the sewer networks
during the defects liability period, the Commission may require the developer to
carry out further CCTV inspection to determine the cause and extent of the problems
that arises. CCTV inspection shall be carried out immediately within 24 hours.
5.5.2 Leakage Test
Leakage is defined as the loss of water in a pipe over 30 minute’s
period. This was determined by adding water from a measuring vessel
at 5 minutes intervals and recording the quantity of water required to
maintain the original level.
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WORK METHOD STATEMENT
Tittle : Method Statement for Sewerage Work
Project : Pembinaan Sekolah Baharu 30 Bilik Darjah Dan Lain-lai Kemudahan Di
Sekolah Kebangsaan Permai, Kemaman, Terengganu
Test Procedure for Leakage Test :
i. Fit an expanding plug, suitably strutted to resist the full hydrostatic
head, at the lower end of the pipe and in any branches if necessary.
The pipes may need strutting to prevent movement.
ii. Fit a similar plug and strutting at the higher end but with access for the
hose and standpipe.
iii. Fill the system with water ensuring that there are no pockets of
trapped air.
iv. Fill the stand pipe of requisite level.
v. Leave for at least two hours to enable the pipes to become saturated,
topping as necessary.
vi. After the absorption period, measure the loss of water from the system
by noting the amount of water needed to maintain the level in the
stand pipe over a further period of 30 minutes, the stand pipe being
topped up at regular intervals of 5 minutes.
vii. For the purposes of this test, the average quantity added for pipes up to
78 in. (450mm) diameter should not exceed 0.2 gallons per hour per
700 linear feet per inch of nominal internal diameter of sewer.
viii. Any leakage, including excessive sweating which causes a drop in the
test water level, will be visible, and the defective part of the work
should be removed and made good.
6. SAFETY PRECAUTION
6.1 Safety induction to be conducted to all new workers that involved to this activity
and safety toll box meeting shall be conducted every day to remind the workers
about concerning the safety.
6.2 All workers shall be provided with PPE (Personal Protective Equipment) and
shall be worn at all time on site. Safety Manager / Safety Supervisor shall ensure
all the workers wear all the safety equipment provided.
6.3 All workers shall be advised to report any accident or injury to supervisor.
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WORK METHOD STATEMENT
Tittle : Method Statement for Sewerage Work
Project : Pembinaan Sekolah Baharu 30 Bilik Darjah Dan Lain-lai Kemudahan Di
Sekolah Kebangsaan Permai, Kemaman, Terengganu
6.4 Proper and adequate provision of temporary signage’s and barricades at
diversions and temporary haul road as necessary (if applicable)
6.5 All workers shall educate on good environmental management practices and well-
disciplined to environment.
6.6 The garbage bin shall be provided at the working area and Supervisor shall ensure
its must be collected regularly and disposed-off at the approved dumpsite.
6.7 All workers shall ensure that all tools and equipment machinery are in good
condition to avoid any oil leakage that could harm to environment.
7. RECORD
Certain inspections, verifications, and tests will be carried out, to ensure the quality and
durability of the product as described in the above procedures, as per the requirements
given in the specification.
