PACKAGE : I Bid Document VOLUME : II - Public Health Engineering

(b) Pressurization : Each valved section of pipe shall be filled with water slowly and the
specified test pressure, based on the elevation of lowest point of the linear section
under test and corrected to the elevation of the test gauge, shall be applied by means of
a pump connected to the pipe in manner satisfactory to the Engineer-in-charge.
(c) Examination under pressure : Under the test pressure no leak or sweating shall be
visible at all section of pipes, fittings, valves, hydrants and welded joints. Any
defective pipes, fittings, valves or hydrants discovered in consequence of this pressure
test shall be removed and replaced by sound materials and the test shall be repeated
until satisfactory to the Engineer-in-charge.
18.11 Wrapping & Coatings.
The wrapping and coating for buried portion of pipeline shall be as per AWWA-C-
203 and as indicated below.
One coat of Shalimar/eq. plasticized coal tar primer cold application.
A hot flood coat of plasticized coal tar with inner wrap at fiber glass resin polyester
tissue followed by a second flood coat of hot coating of plasticized coal tar with outer
wrap of fiber glass resin polyester tissue.
The total thickness of both coating will not be less than 4.5 mm.
Alternately protective coating and wrapping by tapes as per IS 10221 tapping shall
be provided. Total thickness shall not be less than 4 mm, number of layers shall be
minimum 7, thickness of centre cone in microns shall be 90, material of tape
polyester reinforcement, softening point not less than 90 deg, penetration minimum
4mm, pliability 5 deg, tensile strength not less than 160 N/sq. cm, test certificate for
the tapes as per relevant codes shall be furnished.
Where the pipe line is partly above ground and partly underground, the coating use on
the buried portion should be continued well clear of the ground.
Internal painting – The inside of the pipes should be protected against corrosion by the
use of internal painting.
18.12 Flushing and disinfection of mains before commissioning:
The mains intended for potable water supplied should be disinfected before
commissioning them for use.
Distribution system chlorination of new mains : Special care should be taken to ensure
disinfection of new mains. Among possible sources of contamination are sewer
drainage, contaminated soil in the trench, contamination from workmen or their
equipment or both and unavoidable foreign material present in the trench during
construction.
DTS : Detailed Tender Specification. Page 176