The following section describes the testing that shall be performed on the lift station pumps, piping, and force main for acceptance and dedication to the town.
(A) Force main testing.
(1) Generally. Under the observation of the town’s inspector, force mains shall be tested for leakage after installation and prior to final acceptance. The contractor shall be responsible for conducting a hydrostatic pressure test in accordance with AWWA and ASTM standards for testing pressure pipe.
(2) Testing equipment. The contractor shall be responsible for providing all of the equipment and tools necessary to conduct the hydrostatic test including, but not limited to, the following:
(a) Hydrostatic test pump (jockey pump);
(b) Four and one-half inch diameter calibrated pressure test gauge with a range of 0-150 psi graduated in 1 psi increments. The manufacturer’s calibration papers and test date information shall be made available upon the request of the town;
(c) All pipe plugs and/or caps required to perform the hydrostatic test; and
(d) Calibrated/graduated container to measure quantity of water required to be added during the hydrostatic pressure test to maintain specified test pressure.
(3) Hydrostatic pressure testing. The hydrostatic pressure test shall be conducted in accordance with the applicable AWWA standard based on force main material and in accordance with ASTM E103 - “Standard Method for Hydrostatic Leak Testing.” In conjunction with and in addition to the aforementioned standards, the hydrostatic pressure test shall proceed as follows:
(a) The force main shall be completely backfilled prior to testing.
(b) The influent line and effluent discharge shall be appropriately plugged or bulkheaded. The plugs/bulkheads shall be equipped with a minimum of two openings for filling/draining the pipeline and for bleeding air from the line. Thrust blocking restraints are required at each bulkhead and shall be installed in accordance with the bulkhead manufacturer’s requirements.
(c) The test line shall be filled with water at a slow rate to prevent air entrapment.
(d) Trapped air shall be expelled through high point bleed off valves as the line is being filled.
(e) The test tine shall be pressurized to one and one-half times the pump shut-off head as determined from the pump manufacturer’s performance curves or to 100 psi, whichever is greater.
(f) Water shall be added to the test segment to maintain the test pressure for a period of no less than two hours and no more than eight hours. The town’s inspector must be present for at least the first two hours of testing.
(g) The maximum allowable apparent leakage shall be ten gallons per inch diameter per mile per day; however, meeting this criteria shall not preclude the town from requiring repair of any/all visible leakage identified during the test period.
(h) If the force main or any portion thereof fails the hydrostatic pressure test, the contractor shall remove and replace or otherwise repair the force main to the satisfaction of the town, and the force main shall be retested.
(B) Wet well leakage testing. Leakage tests of the wet well shall be observed by the town’s inspector. The wet well shall be tested using the exfiltration test as described below:
(1) After the wet well has been assembled in place, all lifting holes shall be filled with an approved non-shrinking mortar. The test shall be made prior to placing any fill material. If the ground water table has been allowed to rise above the bottom of the wet well, it shall be lowered for the duration of the test. All pipes and other openings into the wet well shall be suitably plugged and the plugs braced to prevent blow out.
(2) The wet well shall then be filled with water. If the excavation has not yet been backfilled and observation indicates no visible leakage after one hour, the wet well may be considered to be satisfactorily water-tight. If the test described above is unsatisfactory or if the wet well excavation has been backfilled, the test shall be continued. A period of time up to 24 hours may be permitted, if the contractor so wishes, to allow for absorption. At the end of this period, the wet well shall be refilled to the top, if necessary and a measuring time of at least eight hours begun. At end of the test period, the wet well shall be refilled to the top and the volume of water added shall be measured. This amount shall be extrapolated to a 24-hour rate and the leakage determined on the basis of depth.
(3) The leakage for each wet well shall not exceed one gallon per vertical foot for a 24-hour period. If the test fails this requirement, but the leakage does not exceed two gallons per vertical foot per day, repairs by approved methods may be made as directed by the town to bring the leakage within the allowable rate of one gallon per foot per day. Leakage due to a defective section or joint or exceeding the two gallon per vertical foot per day maximum shall be cause for rejection of the wet well. It shall be the contractor’s responsibility to uncover the wet well as necessary and to disassemble, reconstruct, or replace it as directed by the town. The wet well shall then be retested at the owner’s expense.
(4) No adjustment in the leakage allowance will be made for unknown causes such as leaking plugs, absorption and the like; such as, it will be assumed that all loss of water during the test is a result of leaks through the joints or through the concrete. The contractor shall take any steps necessary to assure that the water table is below the bottom of the wet well throughout the test.
(C) Manufacturer’s start-up.
(1) Prior to the town’s final inspection of the lift station equipment, the contractor shall coordinate start-up activities with the pump manufacturer’s representative. The town’s inspector must be present at the time of manufacturer’s start-up.
(2) The manufacturer’s representative shall thoroughly test and inspect all components of the system. Any deficiencies in equipment and/or workmanship noted during the manufacturer’s start-up shall be remedied by the contractor prior to final inspection.
(3) Upon successful completion of the manufacturer’s start-up, the manufacturer shall deliver to the contractor:
(a) Three copies of the completed, witnessed report with cover letter certifying that all pumping and electrical equipment has been installed and is operating in accordance with the manufacturer’s requirement;
(b) Five sets of operation and maintenance manuals; and
(c) One complete set of spare parts as specified in this chapter.
(D) Final inspection.
(1) The contractor shall deliver two copies of the manufacturer’s start-up report at the time of final inspection. In addition, the contractor shall provide the following pump test equipment and materials:
(a) Water to conduct test;
(b) Amp/volt meter;
(c) Stopwatch;
(d) Tape or level rod to measure float settings;
(e) Keel to mark float settings on lift station wall;
(f) Calibrated test gauge to measure operating head. The gauge shall be calibrated in feet of water from 0 to 100 feet in one foot increments; and
(g) Manufacturer’s pump performance curves.
(2) The contractor shall provide a connection for the test gauge on the blind flanged tee in the valve vault. The stem connection shall be equipped with a plug valve to close the connection after testing is complete. The connection shall be left in place and shall be suitable for use as an air bleed off. At a minimum, pump testing shall include a manual check of all on-off operations, alarm and run lights; determination of pump capacity for each pump and both/all pumps simultaneously; and determination of pump capacity with the force main full. Full force main shall be verified by a pressure gauge.
(3) The pumping test results must meet or exceed the design pumping criteria approved by the town to successfully pass the final inspection. Any deficiencies noted during the final inspection shall be repaired or replaced by the contractor to the satisfaction of the town and then reinspected and retested prior to final acceptance.
(Ord. 2019-8-26(A), passed 8-26-2019)