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SEWER AND STORM DRAIN CONSTRUCTION

Sewer and storm drain construction shall conform to the details shown on the Plans and

these Specifications. The Contractor shall furnish and install sanitary sewer and drain pipe of

the materials shown or specified in the Contract. Where alternate pipe materials are listed in

the Bid, the Contractor shall bid only one of the alternates shown. Substitution of alternate pipe

material after bid is not permitted.

Sewer and storm drain pipe shall be of the type, class and size as shown or specified in the

Contract, and shall conform to the requirements of Section 50, “Construction Materials”, of these

Specifications for each respective type and class of pipe.

38-3 EXCAVATION AND BEDDING

Trench excavation and bedding for all sewer and storm drain pipe construction shall

conform to Section 19, “Trench Excavation, Bedding and Backfill”, of these Specifications.

The Contractor shall expose the end of existing pipe to be extended, for verification of

alignment and elevation by the Agency, prior to trenching for any pipe that may be affected.

Pipe laying shall proceed after the trench for the pipe has been brought to the proper line

and grade. Pipe laying shall proceed upgrade with the bell or groove end of the pipe placed

upstream. Each section of pipe shall be laid true to line and grade and in such a manner as to

form a watertight, concentric joint with the adjoining pipe. The interior of the pipe shall be

cleared of all dirt and debris as the work progresses. Pipe shall not be laid when the condition

of the trench or the weather is unsuitable, in the opinion of the Agency, because of water or

mud that may interfere with proper jointing. All open ends of pipe and fittings shall be closed

whenever the work is discontinued. For remedial maintenance or improvement projects in

established areas, the Contractor shall coordinate the work so that storm drain systems are fully

operational at the end of each Working Day. No runoff shall be allowed to flow uncontained

through any trenches or excavations without approval of the Agency.

Where plain end vitrified clay pipe with the compression coupling is installed, the Contractor

shall tighten the compression bands as pipe laying proceeds. The first length of pipe laid on

any run, except where a connection is made to an existing line, shall be anchored securely to

prevent movement when each succeeding length is pushed into place. After each compression

band is tightened, the Contractor shall replace and tamp any bedding material that may have

been displaced under the pipe, and particularly under the coupler, before proceeding with the

Circular reinforced concrete pipe with elliptical reinforcement shall be placed with the minor

axis of the reinforcement in a vertical position.

38-4.02 Lines and Grades

All pipe shall be laid in strict conformity to the prescribed line and grade with grade bars set

and each pipe length checked to the top grade line. Three consecutive points on the same

grade of slope shall be used at all times to detect any variation from a straight grade. In case