R-2004-03 adopt portion of “PICM" relating to water system design criteria and improvements

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e e L. Provide a source of fresb water at each end or at multiple points ofa subdivision or development. Provide ways to create circulation and place valves and fire hydrants to allow simple flushing of lines. 2. Where stubs are provided for future extensions, isolate the stubs with a valve and no service connections will be allowed beyond the valve before the line is extended. .Place one full joint of pipe between the valve and the plug. J. New Water Lines Constructed Near Sanitary Sewers and Force Mains and Manholes L. New Water Lines Parallel to Sanitary Sewer and Force Mains: Locate water lines a minimum of 10 feet horizontally, outside wall to outside wall, when parallel to sanitary sewers and force mains. Use the following procedure when site conditions prohibit achieving 10 feet of separation. When the 10 foot separation cannot be achieved the approval of the Director of Planning or his designated appointee must be obtained: a. When a new water line is to parallel an existing sanitary sewer force main or gravity sewer and the 10 foot minimum separation cannot be achieved, the existing sanitary sewer shall be replaced with lined ductile iron pipe, SDR-26 with pressure gaskets, or PVC C-900 150 psi pipe or better and equipped with pressure type joints. b. The water lines and sanitary sewer shall be separated by a minimum vertical distance of 2 feet and at least 4 feet horizontally (per 30 T AC 290.44) measured between the nearest outside walls of the pipes, where the water line shall always be located above the sewer. 2. New Water Lines Crossing New and Existing Sanitary Sewers and Force Mains a. No protection is required if the sanitary sewer is 10 feet below the water line. b. Use the protective requirements given in Table 3.3 and 3.4 for sanitary sewer crossings not 10 feet below the water line. 3. Sanitary Sewer Manholes: Provide a minimum 10 foot horizontal clearance from outside wall of existing or proposed manholes, make manholes and connecting sewers watertight and test for leakage. If a 10 foot clearance cannot be obtained, the water line may be located closer to the manhole when prior approval has been obtained from the Planning Director or his designated appointee by using one ofthe procedures below; however, in no case shall the clearance be less than 4 feet. a. The City of .La Porte may require the water line may be encased in a casing when site conditions dictate or when the water line is within 5 feet of a manhole. The carrier pipe shall be a minimum of I joint of 150 psi pressure class pipe at least 18 feet long and two nominal sizes larger than the water conveyance pipe. The water line may be augured, bore &jacked, or microtunneled past the manhole with at least one 18 foot section of 150 psi pressure pipe installed centered about tbe existing sanitary manhole with pressure grouting of the annular space using a bentonite/clay mixture or other commercial grouts. b. January 2004 Water System Design Criteria Page 11 of 13