(A) General. Inspection of the water system shall be conducted by the City Water Department staff. Several inspections are to be conducted as noted herein. Proceeding to the next phase of construction, prior to the completion of the inspection or approval by the City Water Department personnel, is prohibited. The following on-site inspections shall be required.
(1) Easement site inspection;
(2) Basic installation inspection;
(3) Continuity test; and
(4) Final inspection and certification.
(B) Easement site inspection. The easement site inspection is to provide the Water Department staff with a visual location of the water system easement. The easement shall be located and clearly marked by certified surveyors. These markings shall identify the boundary of the easement, the center line of the water line, and the location of fire hydrants and cut-off valves. Location of water mains shall be marked. These features shall be compared to the approved copy of the engineering plans.
(C) Basic installation inspection. The water system basic installation inspection shall be conducted upon the completion of all trenching operations and the installation of pipes, cut-off valves, fire hydrants, water meter boxes, saddle and corner blocks, and other equipment and features. The inspector shall certify the water system with respect to location, adherence to specifications, material, and other installation features.
(D) Continuity testing.
(1) The purpose of the leakage test is to establish that the section of line tested, including all joints, fittings, and other appurtenances, will not leak, or that leakage is within the limits of the applicable allowance.
(2) Normal operating pressure is usually applied for leakage tests. Pressure should be maintained at a constant level throughout the period of test. Measurement of the amount of additional water pumped in during the test provides a measurement of the amount of leakage, if any.
(3) Air trapped in the line during test will affect test results. Generally the project engineer will establish leakage allowance and indicate methods and procedures for testing. If not, Table Z, below, may be used to determine maximum leakage allowable.
(4) A properly installed line will normally show little or no leakage using the methods described.
(5) A gross leak can usually be traced to a major problem (such as left out gasket, dislodged gasket, broken pipe, loose mechanical joint bolts, inadequate thrust block). Usually these problems are readily detected and quickly repaired.
(6) A minor leak greater than allowable limits is frequently frustrating and difficult to find and repair. The use of dye in the system may be necessary. The best way to avoid this problem is to prevent it during installation.
(a) Vent all high points; use a corporation stop if air release valves are not required.
(b) Double and triple check all mechanical joint bolts.
Table Z: Leakage Allowable, in U.S. Gallons per 1,000 Feet per Hour
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Pipe Size
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Test Pressure
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50 psi | 100 psi | 150 psi | 200 psi | 250 psi | |
Table Z: Leakage Allowable, in U.S. Gallons per 1,000 Feet per Hour
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Pipe Size
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Test Pressure
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50 psi | 100 psi | 150 psi | 200 psi | 250 psi | |
4 inches | 0.38 | 0.54 | 0.66 | 0.77 | 0.85 |
6 inches | 0.57 | 0.81 | 0.99 | 1.15 | 1.28 |
8 inches | 0.76 | 1.08 | 1.32 | 1.53 | 1.71 |
10 inches | 0.96 | 1.35 | 1.66 | 1.91 | 2.14 |
12 inches | 1.15 | 1.62 | 1.99 | 2.30 | 2.56 |
(Ord. 337, passed 4-9-1991; Am. Ord. 345, passed 2-11-1992) Penalty, see § 51.99