RFQ023, Annex II - Technical Specifications of water supply.pdf

ANNEX - II
Detailed Design
Technical Specifications of
CORRECTIONAL CENTER 1
Plumbing Works
Water Supply and Distribution System

Table of Content
1. WATER SUPPLY SYSTEM ......................................................................................................................... 1
1.1 GENERAL ......................................................................................................................................................... 1
1.1.1. Detail Design ................................................................................................................................... 1
1.1.2. Supply and installation .................................................................................................................... 2
1.1.3. Testing and commissioning ............................................................................................................. 2
1.1.4. Maintenance and guaranty ............................................................................................................ 2
1.1.5. Training ........................................................................................................................................... 3
1.2 STANDARDS ..................................................................................................................................................... 3
1.3 WATER DISTRIBUTION NETWORKS ...................................................................................................................... 3
1.3.1. Underground water pipe ................................................................................................................. 3
1.3.2. Above ground water pipe................................................................................................................ 4
1.3.3. Pumping system. ............................................................................................................................. 4
1.4 STORAGE AND HANDLING .................................................................................................................................. 5
2. EXECUTION / INSTALLATION ............................................................................................................. 5
2.1 EXCAVATION FOR PIPE MANHOLES AND U-DITCH ........................................................................................... 5
2.1.1. Excavated Materials Suitable for Reuse .......................................................................................... 5
2.1.2. Pipe Bedding and Laying ................................................................................................................. 6
2.1.3. Backfill to Pipe Trenches ................................................................................................................. 6
2.1.4. Compaction ..................................................................................................................................... 7
2.1.5. Disposal of Spoil .............................................................................................................................. 7
2.2 CUTTING OF PIPES ............................................................................................................................................ 7
2.3 PIPE SUPPORTS ................................................................................................................................................ 7

Technical Specification
ANNEX-II
1. WATER SUPPLY SYSTEM
1.1 General
Plumbing scope covers water distribution piping and slow sand filter treatment system.
New water distribution piping connected from the existing source nearby to the new
construction building as per new design drawing.
Replace old pumping system by the new automatic running pumping system as per new
design drawing.
Slow sand filter water treatment system have to repair and replace sand media inside as per
design drawing.
New additional underground treated water tank near the elevated tank.
The works specified in this section include the detail design, supply and installation, testing
and commissioning, and service under warranty of the following, fully operational, water
supply system networks.
The Contractor shall be deemed to have thoroughly inspected the building site, examined, and
made himself familiar with, all the drawings and specifications for the whole of the works and
allowed in his tender price for all items necessary for the successful completion of the project
in compliance with this specification.
The position of equipment shown on drawings is approximate. The final position will be
determined on site. It is the responsibility to the Contractor to obtain the necessary information
relating to positioning of any equipment.
1.1.1. Detail Design
The designs proposed within the tender documents are a guideline, giving the contractor the
level of quality and performance required for this project only.
The Contractor shall design the complete Works in accordance with the design criteria and
specifications.
The Contractor shall provide the Employer with fully detailed design drawings, schematic,
specifications, calculation notes, material submittals, sample and mock-up (where required)
relating to the Works.
All design work shall be subject to the approval of the Employer.
The Contractor shall be responsible for the submission, re-submission and approval as may be
required of all the documents and drawings.
At the end of the works all approved Contractor Drawings shall be updated to accurately
reflect the Works as constructed, and issued as "As-Built" Documents. The “As–Built”
documents shall include “As-Built” drawings, list of material and suppliers, calculation notes,
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Technical Specification
ANNEX-II
technical documentation for all material and equipment, manual of operation and maintenance,
tests results. As Built documents shall be transmitted under hard copy (2 sets) and electronic
Format.
1.1.2. Supply and installation
The contractor shall be responsible for the provision of all manufactured items, materials and
labor necessary for the proper execution
Before ordering any materials or equipment, the Contractor shall submit to the Engineer for
his written approval, the relevant material submittal document. This includes the full technical
documentation.
Before installation, the contractor shall coordinate with the civil works and other involved
section to facilitate and to make sure the installation will not be hindered by any problem.
The quality of materials and articles supplied for any purpose are to be approved prior to their
use in the works. Wherever practical, samples are to be submitted for approval before bulk
supplies are delivered to the site.
In some cases, mock-up may be required by the Employer prior to start the works.
1.1.3. Testing and commissioning
The complete installation for any part thereof shall be tested, both before and after being
connected up to the requirements of the Engineer.
The Contractor shall be responsible for all performance tests at site and shall be represented by
a capable Engineer during the whole of the period required for the tests.
All materials and equipment supplied or erected under this Contract that fail the tests shall be
replaced or rectified at once by the Contractor without cost to the Employer and the tests shall
be repeated.
All tests shall be conducted in the presence of, and to the satisfaction of Engineer.
The Contractor shall supply all necessary instruments, apparatus, connection, skilled and
unskilled labor required for the tests to the satisfaction of the Engineer; the cost of so doing
shall be included in the Contract Price.
The Contractor shall make accurate records of all tests and shall furnish test certificate and a
schedule of the results in approved form.
All water supply networks shall be disinfected, and washed down before handing over.
1.1.4. Maintenance and guaranty
Guarantee against fault and defects for all equipment and installation shall be available for a
period of six months from the date of the Certificate of Completion.
The cost of the first year maintenance, materials and labor, except the consumable materials is
to be proposed by the contractor at the tender stage, as an option.
Make good all the defects at own expenses.
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Technical Specification
ANNEX-II
Before the issue of the Certificate of Completion, the Contractor shall submit as built
drawings, test certificate, maintenance instructions and spare part list for the complete works
performed.
These instructions shall be typed on good quality paper and neatly bound into a manual. A
sample shall be approved before final submission.
The manuals shall contain the description of system, the operational procedure, the equipment
suppliers and the equipment details...
1.1.5. Training
The Contractor shall provide suitable training for staff, operator and maintenance staff.
Training will start before commissioning the systems and equipment Training session shall
covers information about systems, operation and maintenance.
1.2 Standards
The Design shall be carried out in full compliance with French regulation, and should comply
with good engineering practice and International codes and recommendation.
All workmanship employed, materials, equipment incorporated into the Works shall, except
where specified otherwise or where specific standards are referred to, comply with the latest
issues of the Standards and Codes of Practice, as relevant and appropriate, published by the
following organizations:
NFC French standards or equivalent
1.3 Water Distribution Networks
1.3.1. Underground water pipe
All underground piping work will be high density polyethylene (HDPE) with PE100 pressure
pipes, joints and fittings shall comply with TIS 982-2548, as fabricated by Pipe Industry or
equivalents approved, and fixed in position complete with other necessary fixing and jointing
materials as specified.
All excavation shall be carried out to the required lengths, breaths, depths, inclinations and
curvatures as may be necessary for the construction of the works. Pockets shall be formed for
sockets, flanges, valves etc. So as to give the barrels of each pipe a full support throughout its
entire length. Sufficient timber support shall be provided to prevent trenches from collapsing.
The Contractor is required to provide good de-watering system for keeping the excavation
clear of water at all times. The bottom of all trenches shall be free from mud. All soft or
defective portions shall be cut and filled in with selected excavated materials well
consolidated in layers.
Backfilling shall be commenced only after the pipeline has been tested and approved by the
Engineer.
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Technical Specification
ANNEX-II
Testing of the underground water pipes
After laying, jointing and anchoring, the pipe shall be slowly and carefully charged with
water, so that all air is expelled, allowed to stand full for several days and then tested under
pressure.
A long main shall be tested in sections as the work of laying proceeds, and it is an advantage
to leave the joints exposed for inspection during the testing.
The open end of the pipe may be temporarily closed for testing under moderate pressure by
fitting a blank flange. The end of the pipe shall be secured by struts or otherwise, to assist the
end thrust of the water pressure in the pipe.
The test pressure shall be applied by means of manually operated test pump or, in the case of
long pipes or pipes large diameter, by a power-driven test pump, which shall be left
unattended. In either case precautions shall be taken to ensure that the required pressure is not
exceeded. Pressure gauges shall preferably be recalibrated before the test.
1.3.2. Above ground water pipe
Polyvinyl chloride (PVC) pressure pipes, joints and fittings shall comply with TIS-172523, as
fabricated by Siam Pipe Industry Co., Ltd. or equivalents approved, and comply with the
relevant provisions as set out below:
Water Supply: Class PVC 13.5
All PVC pipes and fittings shall be from a single manufacturer and shall be designed,
fabricated, and installed in accordance with the best practices and methods and shall comply
with these Specifications.
Sizes indicated on the Drawings are the nominal sizes.
All PVC pipes and fittings shall be provided with an ultra violet inhibitor.
1.3.3. Pumping system.
Pumping system cover all the pumps set installed in water supply network to process the
system properly and supply water to serve all the buildings inside Correction Center 1 (CC1):
- Transfer pump (TP-01/02) with capacity 2x4 l/s of flow at 15m of head installed at pond
to convey water from pond to treat by injecting alum and passing through slow sand filter
to store at underground treated water tanks.
- Back wash pump (BP-01) with capacity 8 l/s of flow at 30m of head installed at pump
room near the elevated water tank to back wash the slow sand filter in case the sand filter
not in good condition.
- Transfer pump (TP-03/04) with capacity 2x8 l/s of flow at 20m of head installed at pump
room near elevated tank to convey water from underground treated water tanks to elevated
tank to supply to distribution network.
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Technical Specification
ANNEX-II
1.4 Storage and Handling
Materials and components shall be handled and stored in such a manner as to avoid any
damage and in accordance with all applicable recommendations of the manufacturers and as to
preserve their quality and condition to the standards required by the Contract.
All pipes, fittings and specials shall be properly protected so that no damage or deterioration
shall occur during a prolonged delay from the time of shipment until installation is completed
and the pipeworks is placed in service.
The quantity of materials and components stored on the Site shall be consistent with that
necessary for efficient working.
2. EXECUTION / INSTALLATION
2.1 Excavation for Pipe Manholes and U-Ditch
a. Minimum width of trenches shall be as recommended by the manufacturer. It
shall not in any case be less than nominal diameter of the pipe (U-Ditch) plus
0.3m on each side of the pipe.
b. Minimum depth of cover in areas not subject to vehicular traffic shall be
300mm from the ground surface. When the pipe is laid under road pavement
and areas subject to vehicular traffic the depth shall be 500mm minimum.
c. Excavation in trenches or confined spaces shall be carried out to the specified
or necessary dimensions in all materials encountered.
d. More specifically Rock shall be defined as:
(i) Solid undecomposed boulders or concrete block exceeding 0.10
cubic meters; or
(ii)
Solid unweathered crystalline material in bulk or in banks or
ledges, which in the Engineer's opinion, cannot be broken up or
removed except by the use of explosives.
Soil Material (also referred to as common material) shall be defined as
material that is not rock. The material consists of all soils that can be
excavated by hand or by ordinary excavation equipment or tools.
(iii)
When excavating in asphalt the excavation line shall be marked
and asphalt surface shall be cut neatly with an asphalt cutter
before breaking the asphalt for removal.
2.1.1. Excavated Materials Suitable for Reuse
The Contractor in excavating shall ensure that all materials suitable for re-use are kept
separate and set aside and protected to prevent loss or deterioration.
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Technical Specification
ANNEX-II
2.1.2. Pipe Bedding and Laying
Laying instructions of the manufacturer shall be explicitly followed.
a. The bottom of the excavation trench shall be compacted to 90% M.P. before placing
the bedding material.
b. Bedding for pipes shall be constructed by spreading and compacting screened
granular bedding material over the full width of the pipe trench, by layer of 200mm
and compacted to 95% M.P. After the pipes have been laid, additional material shall,
be placed and compacted equally on each side of the pipes, and where practicable,
this shall be done in sequence with the removal of the trench support.
c. Where socket-jointed pipes are required to be laid on a granular or sand bed, or
directly on a trench bottom, a depression shall be left in the supporting material at the
joint to provide a bed support throughout the length of the barrel of the pipe and to
prevent contamination of the rubber gasket immediately before being forced home.
d. All pipes shall be sound and clean before laying. When pipe laying is not in progress,
the open ends of the pipes shall be satisfactorily covered by plugs or other approved
means to prevent entry of any foreign matter into the pipe. Good alignment shall be
preserved in laying.
2.1.3. Backfill to Pipe Trenches
a. As soon as the excavation is complete to normal grade of the bottom of the
trench, selected granular material filling shall be placed where required by layer
of 200mm thick, compacted and graded to provide firm, uniform and
continuous support for the pipes. This layer shall be compacted to 95% M.P
determined under laboratory conditions or to the pipe manufacturers'
recommendation. Bell holes shall be excavated so that only the barrel of the
pipes bears upon the bedding.
b. Selected granular material shall be placed evenly on each side of the pipes to
mid-diameter and hand tools shall be used to force the selected granular
material under the haunches of the pipes and into the bell boles to give firm
continuous support for the pipes.
c. Granular material shall then be placed to 200 mm above the top of the pipes.
The initial meter of backfill above the selected granular material shall be placed
in 200 mm layers and carefully compacted to 95% M.P.
d. Generally the compaction shall be done evenly on each side of the pipes and
compaction equipment shall not be operated directly over the pipes until
sufficient backfill has been placed to ensure that such compaction equipment
will not have a damaging effect on the pipes.
e. If not enough suitable material is available, the Contractor shall either screen
the excavated soil to remove stones and other materials liable to damage the
pipes or use suitable material from other excavations as proposed by the
contractor and accepted by the Engineer or imported from outside the Engineer
may direct.
f. The remainder of the trench may be backfilled with selected approved material
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Technical Specification
ANNEX-II
2.1.4. Compaction
compacted to 95% M.P, as directed proposed by the contractor and accepted by
the Engineer or imported from outside by the Engineer.
a. The Contractor shall provide compaction equipment suited for compaction of
the various materials specified. In all cases, the compaction equipment and the
method of compaction shall be subject to the Engineer's approval. Not any
manual compaction is allowed.
b. Compacting against foundation, walls, footings, and piers, in trenches, and in
other confined areas, shall be accomplished by manually operated mechanical
tampers.
2.1.5. Disposal of Spoil
All surplus excavated material shall be disposed off with the prior approval of the Engineer
who may prescribe its re-use at another place on the site of the works.
2.2 Cutting of Pipes
Pipes may be cut to shorter lengths using recommended tools.
Cutting of the pipes shall not be allowed for making holes for pipe branch connections.
Connection holes shall made by drilling using approved drilling tools.
2.3 Pipe Supports
Pipe work in building shall be supported by brackets, clips or other fasteners made for such
purpose.
The type and the spacing of supports used shall be suitable for the material of the pipe and its
size.
No support or fasteners shall protrude excessively so as to be a nuisance.
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