4.4 SR 02-21-2023 - Laserfiche WebLink

Home Browse Search

City of Elk River Design Standards When watermain is constructed, separated from the active sy-stem, the Contractor shall still be required to chlorinate, pressure test, and flush the new work in accordance with the specifications. This may require additional work operation to fill and flush the system. The Contractor shall furnish the pump, pipe connections, gauges, and measuring equipment, and shall perform the testing in the presence of ERMU. The pressure gauge for the test shall be an Ashcroft Model 1082 with 4 1/2-inch dial face at 1 psi increments or approved equal. Where permanent air vents are not provided, the Contractor shall pro�ride and install corporation cocks at the high points as needed for release of air as the line is filled with water. Any defective joints, pipe, fittings, valves, or hydrants revealed during the testing or before final acceptance of the work shall be satisfactorily corrected and the tests shall be repeated until the specified requirements have been met. A. Pressure Test: The section being tested shall be slowly� filled with water and the specified test pressure shall be applied after all air has been expelled from the pipe. A hydrostatic pressure of 150 pounds per square inch, gauge pressure, measured at the lowest point of elevation, shall be applied by means of a pump connected to the pipe in a satisfactory manner. The gauge pressure shall be checked after a minimum of two hours. A pressure drop of 1 psi or less over a 2 hour period shall be considered acceptance for the test section. If the pressure drop is greater than 1 psi the Contractor shall investigate the cause and take corrective action. The Contractor must make e�-ery effort to expel all air in the test section which may- be causing a test failure. This may� require the Contractor to tap a corporation at a high point of the main on the top of the pipe to release trapped air. Service pipe shall tvpicallv be tested in conjunction with the main line testing. However, services may� be tested separately- at 100 psi, with the corporation stops open. The Contractor ma�- ha�re to perform additional pressure testing if during the flushing operation there is evidence of debris being flushed out of the system. This may be due to poor construc�ion practices and result in valves not closing tight after having done the original pressure test. Retesting shall be at the discretion of the Water Superintendent. 2. Disinfection of Watermains Before being placed in service, the completed watermain installation shall be disinfected and flushed, and after the final flushing the water shall be tested for bacteriologic qualin� and found to meet the standards prescribed by the Minnesota Department of Health. The disinfection materials and procedures and the collection and testing of water samples shall at a minimum be in accordance with the provisions of A�X��X�A C651, Disinfecting Watermains, and as well as meet the requirements of the Minnesota Department of Health. Where an existing watermain is cut for the installation of a hydrant, for lowering the watermain, or for reasons determined by the Engineer, the pipe and fittings proposed to be installed shall be disinfected prior to installation as follows: (1) The interior of the pipe and fittings shall be cleaned of all dirt and foreign material. (2) The interior of the pipe and fittings shall be thoroughly swabbed or sprayed with a 1 percent minimum hy-pochlorite solution. OO City of Elk River, Minnesota — All rights reserved I 8