SUB-AQUEOUS WATER MAIN

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Location: Providence, RI

Slip-line 4,700 lf of 24” steel water main under the Providence River with a continuous 18” Fuse-able PVC water main.

Contractor: Biszko Contracting Corporation 

Michael Biszko III; (508) 679-0518

Customer: Bristol County Water Authority, 

Pam Marchand; (401) 245-2022

Equipment Used: American Augers DD-625

Final Cost: $468,740.00

Start Date: October 7, 2019

Completion Date: October 24, 2019

Conditions: Push 4,750 lf of drill pipe through the failed 24” Steel water main; pull a caliper pig assembly and a test piece of the Fuse-able PVC back through the 24” Steel. After inspection the test pipe was determined to be acceptable so we had to reinstall the drill pipe under the river and pull back the continuous piece of Fuse-able PVC.

Challenges: The elevation of the entry point was 70 feet lower than the exit point and the center of the 24” existing steel water main was 250 feet lower than entry. The product pipe had a safe pull strength of 175,000 lbs and weighed 185,000 lbs. To overcome this the pipe had to be counter balanced with small amounts of water added as we pulled to fight the buoyancy forces that would cause the pipe to fail. If we had filled the entire pipe with water it would have weighed over 400,000 lbs and failure would have been certain.

Claims: There were no claims for our portion of the work.