November 21, 2017

Division Two - Standards for Water Systems - Chapter VIII. Water Pipe Installation

Chapter VIII. Water Pipe Installation

Sec. 208-1 Trench Excavation and Backfilling for Dedicated Streets

All pipeline trenches in streets dedicated or offered for dedication shall be excavated, backfilled, and compacted in accordance with this Division and Division I Standards for Streets, see Plate Nos. W-4, R-67 and R-68.

Sec. 208-2 Trench Excavation and Backfilling Outside of Dedicated Streets

The engineer in charge of the design and construction of the water system shall specify compaction requirements for the backfill of all waterline trenches not located in streets dedicated or offered for dedication. Prior to acceptance of the water system the developer's engineer shall certify by letter that all trenches have been backfilled in accordance with the specifications.

Sec. 208-3 Pipe Depth

All water mains shall be installed so that the top of the pipe and fittings are not less than 30 inches below finished paving of the street for water mains less than 12 inches in diameter or a minimum cover or 36 inches for mains 12 inches and larger in diameter, unless a greater depth is specified in the excavation and/or encroachment permit. All water service connections shall be installed with a minimum of 30 inch cover within the right of way.

Sec. 208-4 Material Handling

All pipe material shall be handled, laid, blocked and joined in accordance with the manufacturer's recommendations.

All open ends of all water mains being installed shall be properly covered at the end of each day's work to prevent entry of foreign matter, animals, debris, or children.

Sec. 208-5 Thrust Devices

All tees, plugs, caps, bends of more than 5 degrees, hydrant branches or pipe reducers shall be restrained against movement by use of thrust devices.

All reaction or thrust backing devices shall be designed for a minimum static pressure of 200 PSIG. All thrust devices shall be installed in accordance with design data and plans submitted to the engineer. For normal situations, installation shall be in accordance with Plate W-3, "Typical Thrust Block Details." The size and shape of the thrust device shall be designed to prevent movement of the water mains when subjected to the maximum hydrostatic test pressure. Thrust devices shall be cast-in-place concrete, metal harness, or other suitable devices. If the thrust exceeds the bearing value of the surrounding soil, the soil shall be precompacted before placing concrete. To ensure against lateral movement of the water main, valve or fitting where a change in direction of the water main is made by the use of such fittings, a metal harness of tie rods and pipe clamps may be used, except for pipe having rubber-ring type joints. Steel tie rods and pipe clamps shall be galvanized or otherwise rust proofed or painted. All concrete used for thrust blocks shall develop an ultimate compressive strength of 2,000 PSI at 28 days.

Sec. 208-6 Testing

208-6.01 Distribution mains shall be tested to a minimum hydrostatic pressure of design pressure or pipe class. Class 150 pipe shall be tested to a minimum of 150 PSIG. The minimum duration of the test shall be two hours. Before applying the hydrostatic pressure, all entrapped air shall be thoroughly bled off. For all types of water mains, there shall be no visible leakage at any joint or section of pipe and the allowable leakage for the total lengths of all water mains under test shall not exceed that amount specified in "AWWA C600" or “AWWA M23" as appropriate.

208-6.02 All tests shall be made in the presence of the Engineer. Backfill over joints, valves or fittings shall not exceed the initial backfill until they have been inspected, tested, and approved by the Engineer.

208-6.03 When it is necessary to cover the ditch as soon as the water main is laid, the authorized representative of the Engineer may permit the backfilling to be completed prior to testing and disinfecting. If the pipe then tested exceeds the allowable leakage, the pipe must be uncovered, repaired, and tested until it meets the allowable leakage.

Sec. 208-7 Disinfecting

All new or repaired water mains, pumps, tanks, wells, and other facilities before being placed in service, shall be completely disinfected in accordance with "Procedures for Disinfecting Water Mains, AWWA C601" and any additional requirements, as required by the State Department of Health Services or the Kern County Environmental Health Services Department. Water used for testing shall be potable and contain a minimum residual chlorine content of 50 ppm after a time period of 24 hours, after which the water mains and/or waterworks shall be thoroughly drained and flushed. Before being placed in service, a bacteriological test of the system shall be performed in compliance with the requirements of the appropriate health agency.

Location

Public Services Building
2700 M Street, Suite 570
Bakersfield, CA 93301-2370
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Phone: 661-862-5100 
FAX: 661-862-5101 
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