Water Supply Project Specification

8/10/2019 Water Supply Project Specification

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TECHNICAL SPECIFICATIONS

SECTION 6

WATER SUPPLY SYSTEM

6.1 General

These Specifications shall be applied on all water supply system

works, comprising, but not limited to, the water intake structure,

conveyance pipeline, transmission pipeline to the elevated tank, water

elevated tank and distribution network pipeline which shall consist of

various works that are grouped according to their natures and

characters as set out below :

(a) Civil works including earthwork, concrete works, drainage

works, roadway works, outdoor works and others;

(b) Piping works, for the conveyance, transmission and

distribution network pipelines including valves; and

(c) Architectural and metal works including fencing and gate

setting, ladders, anchoring and others.

6.2 Civil Works

6.2.1 Earthworks

The working area shall be confined within the lots demarcated

as shown on the Drawings. The areas shall be cleared, stripped

and leveled to the lines, grades, formations and dimensions as

shown on the Drawings.

The earthworks shall be undertaken and completed for, but not

be limited to, the following :

(a) Trench excavation, bedding and backfilling along the

alignment of the treated water transmission pipeline and

the treated water distribution network pipelines ;

(b) The lot assigned to the elevated water tank;

(c) Preparation for structural foundations of the various

concrete structures;

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(d)Sub-grading for roadways including associated subsidiary

drainage works and flooring of open space in the lots to be

occupied by the elevated tank ; and

(e) Other miscellaneous and ancillary works.

Each work item shall be governed by the respective relevant

provisions of the Technical Specifications, such as :

(a) Open excavation works including pits and trenches

(b) Cobble or broken stone bedding

(c) Sand bedding

(d)Earth or sand backfill works

6.2.2 Concrete Works

Concrete works shall include the following items :

(a) Lean concrete works employing K125 bedding

materials of concrete structures ;

(b) Concrete foundations, footings, blocks, saddles, posts,

etc. to be required for pipes;

(c) Structural concrete works using K225 for water tower

to store treated water; and;

(d)Concrete K250 works for block-out and secondary

concrete to be made for anchoring the equipment,

devices and materials.

All the concrete works shall be executed and completed

conforming to the lines, grades and dimensions as shown on the

Drawings and shall be carried out under the respective relevant

provisions of the Technical Specifications, such as :

(a) Lean concrete works

(b) Structural concrete works

(c) Block-out and second stage concrete works

The Contractor shall be checked the necessity of thrust concrete

block at steel pipe bending points or tee setting points, and

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concrete block, which has required volume, shall be placed if

necessary. All cost incurred for this work shall be included in

the lump sum price for the relevant items in the Bill of

Quantities.

6.2.3 Drainage Works

Drainage works to be undertaken within the premises of the lot

for the facilities shall include side drain ditches which are to be

placed at the side of the roadways as shown on the Drawings.

The drainage works shall also include drainage system to drain

surface water out of the lot to a drainage outfall.

The drainage facilities provided within the premises of the lot of

facilities shall be executed and completed to the lines, gradesand dimensions as shown on the Drawings. Each work item

shall be carried out in accordance with the respective relevant

provisions of the Technical Specifications.

6.2.4 Roadway Works

Paved roadways shall be installed within the premises of the lot

of the facilities. The base course and the roadway pavement are

designed for lighter traffic only and are therefore narrower inwidth and thinner in sections than the normal roads. The

roadways shall be provided with crushed stone and side drain

ditch. All works shall be completed according to the lines,

grades and dimensions as shown on the Drawings and shall

comply with the respective relevant provisions of the Technical

Specifications for the following items :

(a) Sub-grade

(b) Side drain ditches(c) Shoulder

(d)Sodding

6.2.5 Outdoor Works

Outdoor works shall include all structures and facilities to be

constructed within the different lots of the water supply system

complex. The work items are as set out below :

(a) Fencing and gate setting

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(b) Sodding and tree planting on open spaces of the lot

All the above works shall be completed to the lines, grades and

dimensions as shown on the Drawings, and shall include,

except the metal works such as fabrication of fences and gates,the following :

(a) Excavation of pits, trenches for fences, gates, side

drain and ditches

(b) Wet masonry work for side drain ditches

6.3 Mechanical Works

6.3.1 General

Mechanical works for the water supply system shall consist of

erection, installation, fabrication and assembly of the equipment

and materials provided for this system. The works shall be

executed and completed to the lines, positions, places and

dimensions as shown on the Drawings.

All the works shall be carried out by the Contractor until the

system has been certified by the Engineer as fully and

satisfactorily completed and have passed all requiredperformance tests, whereupon the Contractor shall be issued

"Mechanical Completion" and "Performance Test" certificates.

The equipment and materials to be incorporated in the water

supply system include, but shall not be limited to, the

following :

(a) Pipelines for transmission and distribution of treated water

including fittings and valves

(b) Elevated water tank

6.3.2 Standards and Workmanship

All materials shall be new, the best of their respective kinds and

of such quality as are usual and suitable for work of like

character. All materials shall comply with the latest Japanese

Industrial Standards (JIS) or equivalent.

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All workmanship shall be of the highest class throughout to

ensure smooth and vibration free operation under all possible

operating conditions, and the design, dimensions and materials

of all parts shall be such that the stresses to which they may be

subjected shall not render them liable to distortion, undue wear,or damage under the most severe conditions encountered in

service.

All parts shall conform to the dimensions on and shall be built

in accordance with approved drawings. All joints, datum

surfaces, and mating components shall be machined and all

castings shall be spot faced for nuts. All machined finishes shall

be as shown on the Contractor's drawings.

In all mechanical parts, such as screws, bolts, studs, nuts and

threads for pipes etc., the unit of measurement should be in

Metric System.

Standard to be used

All materials to be furnished under the Contract shall conform

to the required standard for materials and test of Japan or

United States of America, or equivalent. The following

standards are referred to and abbreviations shown have beenused.

(a) Japanese Industrial Standard (JIS)

(b) American Society for Testing and Materials (ASTM)

Other International standards may be accepted, provided that

the requirement therein are, in opinion of the Engineer,

equivalent to the above standards. If the Contractor proposes

equivalent standard for such materials, the Contractor shall statethe exact nature of the changes, and shall submit complete

standard, and the information and data on the materials in

English language for the Engineer's approval.

If no standard is indicated, then the relevant Japanese Industrial

Standard, or American Society for Testing and Materials shall

apply.

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All electrical equipment and metal or electrical works shall

comply with the requirements and latest edition of the

following codes and standards, where applicable :

(a) Japanese Electro-Technical Committee's Standard (JEC)

(b) Japanese Technical Standard for Electrical Facilities

(c) Japanese Electric Machine Industry Association's Standard

(JEM)

(d)Japanese Cable-makers Association Standard (JCS)

(e) Local codes, other standard, instructed and/or approved

by the Engineer.

6.3.3 Piping Work

6.3.3.1 General

Steel pipe or PVC pipe shall be used for water lines. All

necessary studs, bolts, screws, nuts, washers, gaskets,

packing, supports, etc., required in connection with the

field assembly of the piping systems shall be supplied by

the Contractor. All gaskets and packing shall be of

approved material and of the type that has been proven

satisfactory for the service to which they will be subjected.

Where pipe is embedded in concrete, it shall be carefully

set to the required lines and grades, and securely braced

and held in place so that no movement shall occur during

concrete placement. Pipe supports to be embedded in

concrete shall be made of material which shall not

deteriorate, weaken or cause damage to the pipe. The

Contractor shall schedule and arrange his work of

installing pipes and pipe supports in coordination with the

Engineer.

The Contractor shall supply and install all pipe hangers,

brackets and supports required for the support of the

piping, including the drilling and caulking for the

expansion anchors and any work incidental to the setting

of such embedded anchors or inserts in concrete.

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Unless otherwise specified, pipe support shall be spaced at

7-feet (2.13 m) maximum. Vertical runs shall be supported

by means of pipe clamps or collars. Hangers and support

shall be painted.

6.3.3.2 Mortar Lined and Enamel Coated Steel Pipe

(a) General

Mortar lined and enamel coated steel pipe materials,

and method of manufacture of straight pipe and pipe

specials shall conform to AWWA-C200 Specifications

or equivalent, subject to the exceptions and

supplemental requirements contained herein. The

pipe, of the diameter and class as specified shall befurnished complete with rubber gaskets, if required,

and all specials and bends shall be provided as

shown.

(b) Cylinder Material

Cylinders shall be fabricated from hot-rolled carbon,

sheets or plates, conforming to ASTM A-570 Grades

C, D, and E, ASTM A-283 Grade D; steel pipeconforming with ASTM A-139, Grade B; or, if

approved by the Engineer, high strength low-alloy

steel conforming with ASTM A-572 Grade 42, or

equivalent JIS standards.

(c) Rubber Gasket

The rubber gasket furnished with the pipe shall be

continuous ring type, made of a special composition

rubber. The gasket shall be so formed and cured as tobe dense, homogenous, and have a smooth surface,

free of blisters, pits, and other imperfections. The

gasket shall be of sufficient volume to fill substantially

the recess provided, when the joint is assembled, and

shall be the sole element depended upon to make the

joint water-tight. The compound shall be of first

grade natural crude, synthetic rubber, or a suitable

combination thereto and shall conform with the

physical requirements listed below :

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Physical Requirements Value

Tensile Strength, min.

Natural RubberSynthetic and combination

Ultimate Elongation, % min.

Natural Rubber

Synthetic and combination

Shoredurometer, Type A

Compression set, percent of

original deflection, max.

Tensile strength after aging,

percent of original tensile

strength, min. (Oxygen

pressure test or air heat test)

160 kg per sq cm150 kg per sq cm

500%

425%

40-65

20%

80%

(d) Welded Joints

Where welded joints are provided, weld bell type

joints may be used, or the bell may be cut back or afiller rod added so as to permit a field weld between

the bell and spigot joint rings.

(e) Pipe Design

Design parameter shall be as follows :

For Cement-Lined Steel Pipes : (Class 150)

Nominal

Diameter (mm)

Steel Cylinders

Thickness (mm)

300 and under

350 - 500

600 - 700

750 - 900

1000 - 1200

4.70

6.00

7.90

9.50

11.10

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Outside diameters of cement-lined, coal-tar coated

and surface painted steel pipes

Nominal

Diameter (mm)

Outside

Diameter (mm)100

150

200

250

300

350

400

450

500600

700

750

800

900

1000

1100

1200

114.30

168.30

219.10

273.10

323.90

391.00

441.80

506.60

557.40661.60

763.20

817.80

868.60

970.20

1075.00

1176.60

1278.20

(f) Lining

The mortar for pipe lining shall consist of one (1) part

of cement to not more than three (3) parts of sand by

weight and shall develop a compressive strength of

not less than 175m kg per sq cm at 28 days. The

cement mortar lining shall be applied by the results.

The process used in the application of the lining shall

produce a smooth dense durable surface, free frompockets, voids, over-sanded areas, blisters, and

excessively cracked areas. Except where otherwise

specified or shown, lining thickness shall be as

follows, with a tolerance of plus or minus twenty-five

percent (25%).

Nominal

Diameter (mm)

Steel Cylinders

Thickness (mm)

under 300 mm300 - 400

6 mm13 mm

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over 400 mm 20 mm

(g) Hydrostatic Pressure Test

All steel cylinders shall be subjected to a hydrostatic

pressure test which stresses the steel to 1760 kg per sq

cm. While under pressure test, all welds shall be

thoroughly inspected, and all parts showing leakage

shall be marked. Cylinders which show any leakage

under test shall be rewelded at the point of leakage,

and subjected to another hydrostatic test.

(h) Specials

(1) Definition

Specials are defined as bends, reducers, wyes,

tees, crosses, outlets, and manifolds, wherever

located, and all piping above ground or in

structures.

(2) Design

Except as otherwise provided herein , materials,

fabrication and shop testing of straight pipe shallconform with the "AWWA Standard for Steel

Water Pipe, 6 Inches and Larger" (AWWA C-

200). Minimum plate thickness of specials shall

be computed using the following formula :

T =

where :

T = plate thickness in inches

D = outside diameter of steel cylinder

in inches

P = design pressure, psi

S = factor of safety 2.50

Y = specified yield point of steel in

psi

but in case shall the design stress (Y/S) exceed

930 kg per sq cm nor shall plate thickness be less

than the following :

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Nominal PipeDiameter (mm)

Pipe Manifolds

Piping Above

Ground Piping in

Structures Fittingsabove Ground (mm)

Fittings

UndergroundInstallation (mm)

300 and under

350 - 500

600 - 700

750 - 900

1000 - 1200

4.70 mm

6.00 mm

7.90 mm

9.50 mm

11.10 mm

4.70 mm

4.70 mm

6.00 mm

7.90 mm

9.50 mm

(3) Outlets, Tees, Wyes, and Crosses

Outlets shall be welded to the steel cylinder of

the pipe. Following this, all outlets larger than

50 mm in diameter shall be provided with steel

reinforcing saddles, wrapper plates, or crotch

plates, or they shall be fabricated in their

entirety of steel plates having a thickness equal

to the sum of the required thickness of the

saddle or wrapper plate, plus the cylinder to

which they are attached.

Such saddles or wrapper plates shall be of steel

plate, at least 1.25 times the thickness of the pipe

cylinder to which the outlet is attached. The

total cross-sectional area of the saddle or

wrapper plate shall be at least 1.25 times the

product of the cut-out length and the plate

thickness of the pipe, as determined in the

equation above. The overall width of the saddle

or wrapper plate shall not be more than 2 times,

and not less than 1.67 times, the maximum

dimensions of the cut-out. Outlets 300 mm and

smaller may be fabricated from schedule 30 or

heavier steel pipe in the standard outside

diameters, i.e., 324 mm, 273 mm, 219 mm, 169

mm, and 144 mm.

Where required, crotch plates shall be provided,

and designed according to the nomographmethod described in AWWA Manual M-11,

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Section 19.5, or AWWA Journal, Vol. 47, No. 6,

June 1955, pp. 617 to 623.

Tees, wyes, and crosses shall either be fabricated

of steel plate or provided with wrapper plates orwith crotch plates. The thickness of the plate or

plates, exclusive of crotch plates. The thickness

of the plate or plates, exclusive of crotch plates,

being such that when multiplied by the diameter

of the opening, shall not be less than 1.25 times

the cross-sectional area of the cutout. Where

tees, wyes and crosses are fabricated from steel

plate with out wrapper plates, the thickness of

the plate shall not be less than 2.5 times therequired plate thickness as shown in the

preceding table for such fittings.

(4) Dimensions

Unless otherwise shown, dimensions of specials

shall conform with "AWWA Standard for

Dimensions for Steel Water Pipe Fittings

(AWWA C-208) for Service in Transmission and

Distribution Systems."

(5) Steel Welding Fittings

Steel Welding fittings shall conform with ASTM

A234.

(6) Ends for Mechanical Type Couplings

Except as otherwise provided herein, where

mechanical-type couplings are indicated, theends of the pipe shall be banded with Type C

collared ends, using double fillet welds. Where

pipe 300 mm (12 in) and smaller is furnished in

standard schedule thickness equals or exceeds

the coupling manufacturer's minimum wall

thickness, the pipe ends may be grooved.

(7) Flanges

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Flanges shall have flat or raised faces. Flanges

shall be attached with bolt holes straddling the

vertical axis of the pipe.

(8) Shop Testing

Upon completion of welding, but before lining

and coating, each special shall be bulkheaded

and tested under a hydrostatic pressure of not

less than one and one-half (1-1/2) times the

pressure for which the pipe has been designed;

provided, however, that if straight pipe used in

fabricating the special has been previously tested

in accordance with sub-clause (h)(2) herein, the

circumferential welds may be tested by a dye

penetration process using Turco-Dy-Check or

approved equal with no further hydrostatic tests.

Any pinholes or porous welds, which may be

reveled by the test, shall be chipped out ad

rewelded, and the special retested.

(9) Lining

All requirements pertaining to thickness,application and curing of lining specified for

straight pipe shall apply to specials, with the

following provisions.. If the special cannot be

lined centrifugally, it shall be lined by hand. In

such case, the lining shall be reinforced with 50

mm x 100 mm No. 12 welded wire fabric

positioned approximately in the centers shall

extend circumferentially around the pipe with

the fabric securely fastened to the pipe. Splicesshall be lapped 100 mm, and the free ends tied

or looped to assure continuity.

(10)Coating

All requirements pertaining to coating specified

for straight pipe shall apply to specials. Unless

otherwise shown, the coating on the buried

portion of a pipe section passing through a

structure wall shall extend 50 mm inside the

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outer surface of the wall or to the wall flange, if

one is indicated. Pipe above ground or in

structure shall be field-painted, as specified in

Painting and Coatings.

(11)Marking

A mark indicating the true vertical axis of the

special shall be placed on the top and bottom of

the special.

(i) Internal Bracing

(1) General

Pipe sections 450 mm and larger shall be braced

internally as soon as practicable after the cement

mortar lining has been applied.

(2) 450 mm through 750 mm Diameter Pipe

Pipe sections shall be braced within 300 mm of

each end with two 2 x 4s wedged in the pipe at

right angles to each other.

(3) Larger than 750 mm through 1200 mm Diameter

Pipe


each end, and at intervals not exceeding 3 m

along the pipe length, with two 2 x 4s wedged in

the pipe at right angles to each other.

(4) Larger than 1200 mm Diameter Pipe


each and, and at intervals not exceeding 3 m

along the pipe length, with two 4 x 4s wedged in

the pipe at right angles.

(j) Cleanliness of Pipe

The interior of each pipe sections and special shall be

clean, and free of foreign materials when they aredelivered to the site of the work.

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(k) Transport and Handling

Coal tar enamel coated steel pipe shall be transported

and handled as specified herein. Any pipe section

that becomes damaged as a result of impropertransporting, handling or stockpiling shall be

repaired to the satisfaction of the Engineer. Where

damaged areas are extensive or where, in the

Engineer's opinion, field repairs are not practicable,

the Engineer may order the Contractor to remove the

damaged pipe section from the site of the work and

replace it with a new section.

Transporting and handling of enamel coated pipe

shall conform with the requirements of AWWA

Standard C-203. After enamel coated pipe has been

delivered to the trench site, any section of pipe which,

in the Engineer's opinion, indicates possible coating

damage, shall be spark tested by the Contractor, in the

presence of the Engineer, at the expense of the

Contractor. Any damaged areas in the enamel

coating shall be field-repaired using hot coal tar

enamel or the section of pipe replaced as specified

above.

(l) Installation of Piping

(1) General

Unless otherwise provided, the Contractor shall

furnish and install all pipes, specials, fittings,

closure pieces, valves, supports, bolts, nuts,

gaskets, jointing materials, and all otherappurtenances as shown and as required to

provide a complete and workable installation.

Where pipe support details are shown, supports

shall conform thereto, and shall be placed as

indicated; provided, that the support for all

exposed piping shall be complete and adequate,

regardless of whether or not supporting devices

are specifically shown. Concrete thrust blocks,

anchor blocks, or welded joints shall beprovided at all junctions, changes in direction

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exceeding 11-1/2 degrees or where otherwise

shown. At all times when the work of installing

pipe is not in progress, all openings into the pipe

and the ends of the pipe in trenches or structures

shall be kept tightly closed to prevent entrance ofanimals and foreign materials. The Contractor

shall take all necessary precautions to prevent

the pipe from floating due to water entering the

trench from any source, and shall assume full

responsibility for any damage due to this cause,

and shall, at his own expense, restore and

replace the pipe to its specified condition and

grade, if it is displaced due to floating. The

Contractor shall maintain the inside of the pipefree from foreign material, and in a clean and

sanitary condition until its acceptance by the

Engineer.

(2) Laying

Trenches shall be in a reasonably dry condition

when the pipe is laid. Necessary facilities,

including slings, shall be provided for lowering

and properly placing the pipe section in the

trench without damage. The pipe sections shall

be laid to the line and grade as shown, and they

shall be closely jointed to form a smooth flow

line. Immediately before placing each section of

pipe in final position for jointing, the bedding

for the pipe shall be checked for firmness and

uniformity of surface.

(3) Rubber and Gasket Joints

The rubber gasket joints shall be made by

properly lubricating the rubber gasket with a

suitable vegetable compound soap before it is

placed in the groove, with care taken to equalize

the stress in the gasket around the circumference

of the joint. The gasket shall not be twisted,

rolled, cut, crimped,, or otherwise injured or

forced out of position during the closure of thejoint. A "feeler" gage shall be used to check the

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position of the rubber gasket after the joint has

been telescoped.

(4) Field-Welded Joints

Field welding of pipe joints shall conform with

the requirements of the "AWWA Standards for

Field Welding of Steel Water Pipe Joints"

(AWWA C206). Prior to welding, the joint shall

be made up in accordance with Subsection (l)(3)

and(l)(5) herein. Such joints shall be inspected

and approved by the Engineer before any

protective coating is placed around the outside

of the joint.

(5) Protective Coatings

With pipe smaller than 450 mm in diameter,

before the spigot is inserted into the bell, the bell

shall be daubed with mortar containing one (1)

part of cement to three (3) parts of sand by

weight. The spigot end then shall be forced to

the bottom of the bell, and excess mortar on the

inside of joint hall be swabbed out. With pipe450 mm in diameter and larger, joints shall be

pointed on the inside with mortar, as specified

for field joints in AWWA Standard C205, after

the backfill has been placed. After coated pipe

section have been joined, the coating shall be

made continuous across the joints, forming a

coating equivalent to the factory-applied coating

of adjacent pipe sections. Coating and spark

testing of coal tar enamel field joints shall be asspecified in AWWA Standard C203, and shall be

performed at the expenses of the Contractor.

The use of coal tar tape to provide the required

protection shall not be permitted.

After the pipe sections on cement mortar coated

pipe have been joined, but before backfilling has

been completed, the outside annular space

between pipe sections shall be completely filledwith grout. The grout shall be poured in such a

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manner that all exposed portions of metal joints

shall be completely protected with cement

mortar. Grout shall consist of one (1) part of

cement to three (3) parts of sand, by weight, and

shall be sufficiently fluid to permit it to bepoured into the joint space. Exterior field joints

shall be coated with cement mortar, retained by

suitable forms so as to bridge the joint. The

mortar shall be compacted within the form to

produce dense coating without voids. The joint

coating shall be kept moist until the backfill is

placed.

(6) Butt-straps

Where a butt-strap is used, both the interior and

exterior surfaces of the but-strap shall be given a

coating equivalent to the factory-applied coating

of the adjoining pipe sections. Mortar coating

shall be reinforced with wire mesh. The mortar

lining shall be reinforced with wire mesh,

where the exposed length of the butt-strap, as

measured between the ends of the connected

pipe section, exceeds 100 mm. Butt-straps used

as closure pieces shall be provided with hand

holes for repair of the lining.

6.3.3.3 Small Steel Pipe

Unless otherwise shown, galvanized steel pipe, sizes less

than 100 mm in diameter and smaller, shall conform with

the requirements of the "Specifications for Black and Hot-

Dipped Zinc Coated (Galvanized) Welded and SeamlessSteel Pipe for Ordinary Uses" (ASTM A-120), and shall be

Schedule 40. Galvanized steel pipe shall not be cement

mortar-lined, unless otherwise specified. Fittings for

galvanized steel pipe shall be of galvanized malleable iron,

Galvanized and black steel pipe shall not be used for

buried service, except where shown on the Drawings.

Galvanized steel pipe for service connections shall be

allowed only as specifically shown on the Drawings. Thepipe shall be wrapped with a 500 micron thick PVC tape to

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a total thickness of 1000 microns, with half width

overlapping. PVC tape shall be applied in accordance with

the manufacturer 's recommendations.

6.3.3.4 PVC Pipes

Polyvinyl chloride pipes shall conform to JIS K6742 and/or

K6741, and be laid and jointed in accordance with the

manufacturer's instructions and to the Engineer's

satisfaction.

After the pipes have been laid, they shall be left exposed,

haunched or surrounded in concrete or covered with spoil

as required on the Drawings. Where covering with spoil is

done, care shall be taken to prevent damage due to largestone striking the pipe by removing large stones from the

layer of spoil immediately against the pipe or by other

means.

6.3.3.5 Pressure and Leakage Testing

(a) General

The Contractor shall furnish all equipment, labor and

material, including taps, valves, and bulkheads, as

required, exclusive of water and water meter testing.

The water and any water meter used for testing shall

be furnished by the Employer, but the Contractor

shall provide the facilities necessary to convey the

water from the designated source to the points of use.

All testing shall be done in the presence of the

Engineer.

(b) Pipeline Testing

All pipelines shall be thoroughly flushed out with

water prior to testing. The Contractor shall test the

pipeline in section prior to permanent resurfacing

after the trench is backfilled, but with joints exposed

for examination, except in heavily traveled roadways.

Maximum length of test sections shall be 500 metres

for distribution mains and 1, 000 metres for

transmission mains, unless otherwise approved by theEngineer. Where test sections are approved which

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exceed the above maximum lengths, the allowable

leakage for the lengths in excess of the maximum

allowable shall be reduced by fifty percent (50%).

The pipeline shall not be filled with water until the

following curing period have elapsed.

Description

Minimum

Allowable Time

1.

2.

3.

Cement Mortar Linings

Cement Mortar at Joints

Concrete Thrust Block

14 days

8 hours

a. Standard Cement

b. High Early Strength Cement

7 days

39 hours

The pipeline shall be prepared for testing by closing

valves, when available, or by placing temporary

bulkheads in the pipe and filling the line slowly with

water. During the filling of the pipe, and before the

application of the specified test pressure, all air shall

be expelled from the pipeline. To accomplish this,

taps shall be made, if necessary, at profits of highest

elevation, and after completion of the test; and taps

shall be tightly plugged, unless otherwise specified.After the line or section thereof has been completely

filled, it shall be allowed to stand under a slight

pressure for a minimum of forty-eight (48) hours, to

allow the escape of air from any air pockets, and to

allow the pipe or mortar to absorb as much water as

possible.

During this period, all exposed pipes, fittings, valves,

hydrants, joints, coupling shall be examined for leaks.if found to be cracked or defective, they shall be

removed and replaced by the Contractor with sound

material at his own expense. The pipeline shall then

be refilled, and all bulkheads, joints, and connections

shall be examined for leaks. If any are found, these

shall then be refilled, and all bulkheads, joints, and

connections shall be examined for leaks. If any are

found, these shall be stopped. The test shall consist of

holding the test pressure on each section of the linefor a period of two (2) hours. The test pressure at the

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lowest point shall be 690 KPa (100 psi) or 1.0 MPa (150

psi) according to the class of pipe installed, class 100

or class 150, and as approved by the Engineer.

Pressure gauges shall also be provided at all ends of

the section tested. The water necessary to maintainthe pressure shall be measured through a meter or by

other means satisfactory to the Engineer. The leakage

shall consider the amount of water entering the

pipeline during the two-hour test period. The

allowable leakage for asbestos cement pipe shall not

exceed the values listed in Table 1 of the "AWWA

Standard for Installation of Asbestos Cement Pipe"

(AWWA C-603), The allowable leakage for cast iron

pipe or ductile iron pipe shall not exceed the valueslisted in Table 3 of the AWWA Standard for

Installation of Cast Iron Water Main (AWWA C-600).

All other types of pipes shall have an allowable

leakage not exceeding 1.85 L/mm, (20 gal/in) of

diameter of pipe per kilometer per day. Should any

test of a section of pipeline disclose joint leakage

greater than that permitted, the Contractor shall, at

his own expense, locate and repair or replace the

defective pipe, fitting, joint coupling, or otherappurtenance. The test shall then be repeated until

the leakage is within the permitted allowance.

Closure pieces between newly installed and existing

mains shall be tested after the pipe has passed the

pressure and leakage test specified above. The test

shall include subjecting the joint to a pressure of 345

KPa (50 psi) for a period of five (5) minutes, and

visually checking for leakage. All visible leaks shallbe repaired by the Contractor at no expense to the

Employer.

6.3.4 Valves

6.3.4.1 General

The Contractor shall furnish and install all valves as

specified herein, and as shown on the Drawings. All

valves shall be new and of current manufacture.

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Flanged valves may be plain faced with serrated gasket

surface or raised. Flanges of valves for water working

pressure of 1.2 MPa (175 psi) or less shall be faced and

drilled of 125-lb American Standard dimensions; flanges of

valves for water working pressures greater than 1.2 MPa(175 psi) shall be faced and drilled to 250-lb American

Standard dimensions.

Each valve body shall be tested under a test pressure equal

to twice its design water working pressure.

All valves shall be provided with a exterior protective

coating in accordance with the pertinent provisions of the

Specifications.

When the operating nut of a buried valve is located more

than 1.5 metres below the ground surface, the Contractor

shall provide and install in the valve box a steam

extension. The bottom of the extension shall be securely

fastened to the operating nut of the valve, and the top of

the extension shall be centered in the valve box.

The Contractor shall furnish a minimum of six (6) tee-

handle valve keys of variable lengths, sufficient to permitoperation of all buried valves regardless of depth, by

operators of average height working in normal position.

Where the number of valves to be provided exceeds thirty

(30) units, the Contractor shall provide one (1) valve key

for every five (5) additional valves or a fraction thereof.

Operating nut shall turn counter-clockwise to open.

6.3.4.2 Gate Valves

(a) Valves

All valves shall conform with the "Standard Systems"

(AWWA C509). Gate Valves, where the pipeline

design pressure is 1.0 MPa (150 psi) or less, shall be

designed for a minimum water working pressure of

1.0 MPa (150 psi), and shall be cast iron bodied, with

resilient seats applied to the body and gate. Disksshall be cast iron with bronze disc rings, and the seat

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tested with twice the specified rated pressure

applied to one side of the gate and zero pressure

on the other side. The test shall be made in each

direct across the gate. Under this hydrostatic

test, the Contractor may make special provisionsto prevent leakage past the seats. No part of the

valve or gate shall be permanently deformed by

the test.

(5) Torque Test

A prototype of each size shall be overtorqued in

the closed and open positions, to demonstrate no

direction of the valve stem or damage to the

resilient seat as evidenced by failure to seal at

rated pressure. The applied torque shall be 250

ft-lb for 3 and 4 NRS valves, and 350 ft-lb for 6,

8, 10, and 12 NRS valves (1.0 ft-lb = 0.736

Newton-meter = 0.66 kg-m).

(6) Leakage Test

Two prototype valves of each size chosen by the

Engineer to represent the extremes of seatcompression shall be fully opened and closed to

a seal for 500 complete cycles with sufficient flow

that the valve is at 200 psi pressure differential at

the point of opening and closing. The valves

shall be drop-tight under rated pressure

differential applied alternately to each side of the

gate after completion of the tests.

(7) Pressure Test

One prototype of each valve size shall be tested

to 500 psi with the closure member in the open

position. There shall be no rupture or cracking

of the valve body, valve bonnet, or seal plate.

Leakage at pressure-containing joints shall not

be cause for failure of the test.

6.3.4.3 Butterfly Valves

(a) Valves

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Butterfly valves shall conform with the "AWWA

Standard for Rubber -Seated Butterfly Valves"

(AWWA C504) subject to the following requirements.

Valves shall be of Class 150B and, unless otherwise

specified, may either be short-bodied to long-bodied.Shaft seals shall be designed for use with standard

split V-type packing or "O" ring seals. The valve ends

shall be either flanged or of the wafer type, except

where otherwise shown on the Drawings.

(b) Operators

Operators shall conform with the above-referenced

AWWA Standard, subject to the following

requirements: Valves shall be equipped with 50 mm

square operating nuts or with handwheels 600 mm

maximum diameter, as specified, and shall be

provided with watertight gear housings.

The Contractor shall furnish a written certification

stating that the operator torque has been computed,

and the operators have been sized to meet the full

AWWA Class specified in Subsection (a) herein.

(c) Testing Requirements

(1) Performance Tests

Each valve that has the operator directly on the

valve shall be shop-operated three times from

the fully closed to the fully opened position, and

the reverse, under a no-flow condition, to

demonstrate that the complete assembly is

workable.

(2) Leakage Tests

Each valve shall be shop-tested for leaks in the

closed position. The test shall be conducted

with the body flanges in a horizontal plane.

With the disc in the closed position, air pressure

shall be supplied to the lower face of the disc for

the full test duration as follows :

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6.3.4.5 Air Vacuum and Air Release Valves

Air vacuum and air release valves shall have threaded

connections. The bodies shall be of high-strength cast iron,

and the float shall be of stainless steel. Float guidesbushings, lever pens and all other internal parts shall be

constructed of stainless steel or bronze. Seat washers and

gasket shall be of a material insuring water-tightness with

a minimum of maintenance. Valves shall be designed for a

water working pressure of not less than 1.0 MPa (150 psi).

All valves shall be designed to automatically operate so

that they will : (a) positively open under atmospheric

pressure (as water drains from the body of the valve, it will

allow air to flow into the pipe while it is being emptied);(b) positively close as water, under low head, fills the body

of the valve ; (c) not blow-shut under high velocity air

discharge; and (d) permit the escape of accumulated air

under pressure while the pipe is in operation. The valves

shall be either direct or lever operating.

6.3.4.6 Air Vacuum Valves

Air vacuum valves, of sizes up to and including 100 mm (4

in) in diameter, shall have threaded connections except

where otherwise shown on the Drawings. The bodies shall

be of high strength cast iron, and the float shall be of

stainless steel. All internal parts such as float guides,

bushings, and baffle retaining screws, etc., shall be either

stainless steel or bronze. Seat washers and gaskets shall be

of a material insuring water tightness with a minimum of

maintenance. Valves shall be designed for a water working

pressure of not less than 1.0 MPa (150 psi). All valves shall

be designed to automatically operate so that they will : (a)

positively open under atmospheric pressure (as water

drains from the body of the valve, it will allow air to flow

into the pipe while it is being emptied; and (b) positively

close as water, under low head, fills the body of the valve;

(c) not blow shut under high velocity discharge.

6.3.4.7 Air Release Valves

Air release valves, up to an including 100 mm (4 in.) indiameter, shall have threaded connections, except where

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otherwise shown on the Drawings, and shall be designed

for a water working pressure of 1.0 MPa (150 psi). The

body shall be of high strength cast iron, and the float shall

be of stainless steel. All internal parts, except the seat,

shall be of stainless steel or bronze. The seat shall be ofmaterial insuring water tightness with a minimum of

maintenance. The valves shall be designed to

automatically permit the escape of accumulated air under

pressure while the pipe is in operation. The valves shall be

either direct or lever operating.

6.3.4.8 Float Valves

Float valves shall be as shown on the Drawings.

6.3.4.9 Miscellaneous Small Valves

Valves 50 mm and smaller, unless otherwise specified shall

be all bronze or brass with threaded connections designed

for a water working pressure not less than 1.0 MPa (150

psi).

6.3.4.10 Plug Valves

Plug valves shall be lubricated 50 mm semi-steel

straightway valves with a working pressure of 175 lb. The

valves shall be wrench-operated, two-bolt cover type with

screwed ends. A complete locking device assembly shall

be provided for each valve, where indicated on the

Drawings.

6.3.4.11 Pressure Reducing Valves

The pressure reducing valve shall be of the diaphragmtype, equipped with a pilot spring to provide a range of

downstream pressure settings. the pressure reducing

valve shall be designed for a minimum water working

pressure of 1.0 MPa (150 psi), and shall be factory tested

under a hydrostatic pressure of at least 2.0 MPa (300 psi).

The valve body and cover shall be cast iron, meeting the

requirements of ASTM A48. The valve shall have flanged

ends, and the valve disc shall be non-metallic and

renewable. The main valve trim shall be of bronze, asspecified in ASTM Specification B62, and the valve seat

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shall be of brass, with type 18-8 stainless steel trim. The

diaphragm shall be of heavily reinforced synthetic rubber,

and shall be fully supported by the valve body. The valve

shall be coated in accordance with the pertinent provisions

of the Specifications.

6.3.4.12 Pressure Relief Valves

The pressure relief valve shall be of the diaphragm type.

The disc shall be non-metallic and renewable, and the

valve seat shall be replaceable. The main valve trim shall

be of bronze, conforming with ASTM Specification B62.

The pilot control shall be fully supported by the valve

body. The valve shall be coated in accordance with the

pertinent provisions of the Specifications.

6.3.4.13 Fire Protection System

(a) Fire Hydrant Heads

Fire hydrant heads shall be designed for a minimum

pressure of 1.0 MPa (150 psi) and have a 150 mm (6

in) flanged inlet, a 100 mm (4 in) streamer hose

outlets shall have hose caps and chains. Fire hydrantheads shall have a heavy duty body of bronze

conforming with ASTM Specification B-62 and shall

be cast-iron body in accordance with AWWA

Standard for Wet-Barrel Fire Hydrants (AWWA C503)

with bronze working parts. The stem shall be

provided with at least two (2) O-rings. Hydrant

valves shall open counter-clockwise. Burys for the

hydrants may be a commercial product or locally

fabricated.

(b) Wrenches

The Contractor shall provide three (3) sets of

pentagon spanner wrenches that will operate all

valves specified.

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6.3.5 Welding

All welding shall be done either manually by the shielded

metallic arc process or automatically by the shielded arc or

submerged arc method.

The Contractor shall submit a welding procedure for the

approval of the Engineer in the same manner as the drawings.

After the welding procedure has been approved, the Contractor

shall record it on a special drawing, which shall thereupon

become one of the drawings of the Contract. Weld sizes and

types shall be shown on all Contractor's drawings where

welding is required.

Plates to be joined be welding shall be accurately cut to size androlled by pressure to the proper curvature, which shall be

continuous from the edge. Flattening the curvature along the

edges with correction by blows shall not be allowed. The

dimensions and shape of the edges to be joined shall be such as

to allow thorough fusion and complete penetration, as

necessary, and the edges of plates shall be properly formed to

accommodate the various welding conditions. The surfaces of

the plates for a distance of 25 mm from the edge to be welded

shall be thoroughly cleaned of all rust, grease and scale, tobright metal.

Qualification of Welding Procedure

The technique of welding employed, the appearance and

quality of the welds made, and the methods used in correcting

defective work, shall conform to the American Welding Society

(AWS) Standard D.I.I., or other approved equivalent standard.

Qualification of Welders and Welding Operators

All welders and welding operators to be assigned to the works

shall have passed a qualification test, within the preceding six

months, for Welders and Welding Operators, in accordance

with JIS Z 3801 or equivalent. The Contractor shall furnish the

Engineer with three (3) certified copies of report of the results of

physical test of specimens welded in the qualification tests. If,

in the opinion of the Engineer, the work of any welder at any

time appears questionable he shall be required to pass the

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appropriate re-qualification test. All costs of qualification tests

shall be borne by the Contractor.

Welding Electrodes

The welding electrodes shall conform to JIS Z 3211 or 3212, low

hydrogen type covering or equivalent.

Stainless type weld metal, where used in the water passages for

protection against pitting, shall be of chromium nickel steel.

The type, chemical composition for this purpose shall be

subject to approval of the Engineer.

6.3.6 Protection, Cleaning and Painting

The following surfaces shall not be painted ;

(a) Surface which will be buried in concrete.

(b) Parts made of stainless steel, bronze or brass.

(c) Surfaces in rolling or sliding contact.

(d)Surfaces such as gear teeth.

(e) Wire ropes.

All machined parts of bearing surfaces shall be cleaned and

protected from corrosion before leaving the manufacturer's

shop, by the application of an approved rust preventive

compound or a peelable plastic film. Where the latter is

impracticable, such parts shall be heavily covered with high

melting point grease or other approved materials. Before

commencement of erection such parts shall be cleaned with

solvent and lapped or polished bright. The Contractor shall

supply the materials necessary for each cleaning.

All parts, other than machined parts, which shall be exposed

after erection shall be thoroughly cleaned and given at least

three (3) coats of best quality approved primer and at least two

(2) coats of best quality approved finish paint before leaving the

manufacturer's shop. The Contractor shall perform to the

equipment touch-up painting at the site after erection, except

such apparatus as panels and instruments, which shall be finish

painted under approved procedures before shipment. The

Contractor shall supply paint materials and necessary tools,

which are used at the Site, for the Plant.

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Primer shall be applied to surfaces in accordance with the paint

manufacturer's instructions. The surfaces shall be wiped clean

immediately prior to applying the paint. The primer and finish

coats of paint shall be applied using the methods and

equipment recommended by the manufacturer. The paintsystem selected shall have a proven life expectancy of not less

than five (5) years in the atmosphere prevailing at the Site.

The internal surface of all pipes shall be cleaned out by

approved methods before installation and again prior to

commissioning, to ensure freedom from dirt, rust, scale,

welding slag, etc. All exposed pipes shall be colour coded for

identification after erection is completed. The code system

shall be approved by the Engineer.

The final colour of all equipment shall be approved by the

Engineer but the Contractor shall propose a colour scheme for

the equipment and shall submit colour chips or paint samples.

A colour chip shall be included with the approved colour

schedule, for each type of finish to be applied at the Site.

Documents

Water Supply Project Specification