Wastewater Thickening Room Drain Pipe Replacement

2026-11-03

The Contractor shall furnish all labor , materials , equipment , and installation necessary for the replacement of the existing drain system serving the Thickening Room , located in the Process Building basement . The existing piping , originally installed circa 1988 , has failed and requires full replacement . The work involves multiple constraints and complexities , as outlined herein . The existing drain piping is ductile iron and is located approximately 13 feet above the floor . Process pumps are located directly below the project area , with additional piping , valves , and electrical conduit in close proximity . The Thickening Room and associated systems shall remain operational throughout the duration of the project . Any required shutdowns shall be minimized and shall be coordinated in advance with Wastewater Treatment Facility staff . The Contractor shall be solely responsible for providing all necessary scaffolding , rigging , and access equipment required to safely access , remove , and reinstall the piping . The Contractor shall carefully consider the safe removal of the existing piping . The piping is heavy and contains years of accumulated debris , as documented in the accompanying photographs . Removal shall be performed in controlled sections and with appropriate protective measures to prevent damage to equipment , piping , and facilities located below . Replacement piping shall be Schedule 80 PVC . The system shall consist of one ( 1 ) continuous 6 - inch diameter main run approximately 110 linear feet in length . The overall system shall also include thirteen ( 13 ) inlet pipes , each 4 inches in diameter , six ( 6 ) 4 - inch vent pipes , and two ( 2 ) 2 - inch vent pipes . There is a total of twelve ( 12 ) cleanouts throughout the piping system to be reinstalled , as marked . All piping supports and hangers shall be installed in accordance with applicable codes and standards . Hanger material shall be stainless steel . A copy of the 1988 Secondary Upgrade Plans , Sheet P - 8 , is provided , with the piping to be replaced clearly identified . All measurements are the responsibility of the Contractor to be confirmed in the field . The Contractor shall be responsible for the proper disposal of all removed materials and existing piping . Upon completion of the work , the Contractor shall leave the project area clean and free of debris . Cleaning shall include , but not be limited to , floors , piping surfaces , walls , and doors . The area is subject to inspection before City staff will approve project completion .

New Hampshire

2026-04-28