Technical Specification - UNDP

1.34 Road Crossing
Road crossing should be performed by digging the trench across the road and install
the UPVC pipes inside a steel sleeve bigger in diameter. The crossing should be
carried out with the coordination with the Municipality.
1.35 Tests for Watertighness of Structures
Inspection and testing of structures should be carried out as required in accordance
with section 6 of CP 114, CP 115 : Part 2 : 1969 or section 9 of CP 110 : Part 1 : 1972
as appropriate. Testing for water tightness should be in accordance with the
specifications.
Water retaining structures shall be capable of withstanding the following tests for
water tightness with full care to protect the structure from damages by considering the
right ways to fill the structure with water or by loading the earth pressure by carrying
out the backfilling:
When ordered by the Engineer, the structures shall be filled with water by the
Contractor at rates and to the depths ordered by the Engineer and kept filled for one
week.
The water used need not be equal to normal drinking water but the source of the water
shall be approved by the Engineer.
The structure when filled shall satisfy the test if at the end of one week no leakage is
apparent.
Upon completion of the test the Contractor shall empty the structures and dispose
satisfactorily of the contents. He shall clean the structures and any equipment therein
of all deposits left by the testing water.
All pipelines shall be tested for water tightness in accordance with the specifications.
Roofs to potable water retaining structures should be watertight and should be tested
on completion by either of the following methods:
A. flood the roof to a minimum depth of 25 mm of water for
a period of 24 h;
B. use a hose or sprinkler system to obtain sheet flow over
the whole rate of the roof for a period of not less than 6 h.
In either case the roof should be considered satisfactory if no leaks or damp patches
show on the soft.
The tests referred to above, shall be performed at the Contractor's expense and shall
be considered incidental to the Contractor.
1.36 Testing on Completion
The Engineer may before issuing the Certificate of Completion require any part of the
Works to be tested for conformity with the Specifications and according to the
manufacturer's instructions. Such tests shall be made at the Contractor's expense.
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