(A) All domestic water lines must be pressure tested with the town’s inspector present. The owner/contractor shall notify the Water Department at least 72 hours in advance of testing. The contractor shall provide all equipment necessary for the testing.
(B) Each section of pipe shall pass a pressure and leakage test in accordance with the most recent requirements of AWWA Standard C600-93, Section 4.1 - Pressure and Leakage Test. Prior to testing, lines shall be thoroughly flushed at a minimum rate of 2.5 fps. Flushing shall be accomplished by partially opening and closing valves and hydrants several times under the expected line pressure.
(C) Thrust blocks, if used, shall have been in place for not less than ten days prior to testing lines.
(1) Test restrictions.
(a) Test pressure shall not be less than one and on-half times the working pressure at the lowest point along the test section, or 150 psi, whichever is greater, but shall not exceed the pipe, fitting or thrust-restraint design pressures at any point. Test pressure shall not vary by more than ±5 psi for the duration of the test, which shall not be less than two hours.
(b) Valves shall not be operated in either direction at differential pressure exceeding the rated valve working pressure. Use of a test pressure greater than the rated valve pressure can result in trapped test pressure between the gates of a double-disc gate valve. For tests at these pressures, the test setup should include provisions, independent of the valve, to reduce the line pressure to the rated valve pressure on completion of the test. The valve can then be opened enough to equalize the trapped pressure with the line pressure, or opened fully if desired.
(c) Test pressure shall not exceed the rated pressure of the valves when the pressure boundary of the test section includes closed, resilient-seated gate valves or butterfly valves. No test sections shall exceed five miles in length without prior approval from the town’s inspector or representative.
(2) Test procedures.
(a) All newly laid pipe or any newly valved section shall be subjected to a hydrostatic pressure of at least one and one-half times the working pressure at the point of testing or 150 psi, whichever is greater. The specified test pressure, which is based on the elevation of the lowest point of the line or section being tested as corrected to the elevation of the test gauge, shall be applied by means of a pump connection to the pipe in a manner satisfactory to the town. Allow the system to stabilize at the test pressure before conducting the leakage test.
(b) Before applying the specified test pressure, air shall be expelled completely from the pipe, valves and hydrants. If permanent air vents are not located at high points, the contractor shall install corporation cocks at such points so that air can be expelled as the line is slowly filled with water. After the air has been expelled, the corporation cocks shall be closed and the test pressure applied. At the conclusion of the pressure test, the corporation cocks shall be removed and plugged, or left in place if requested by the town.
(c) All exposed pipe, fittings, valves, hydrants and joints shall be examined carefully during the test. Any components damaged during or after the pressure test shall be repaired at the contractor’s expense. The test shall be repeated until the results are satisfactory to the town.
(3) Allowable leakage.
(a) Leakage shall be defined as the quantity of water that must be supplied into the newly laid pipe or any valved section to maintain pressure within 5 psi of the specified test pressure after the pipe has been filled with water and the air has been expelled. Leakage shall not be measured by a drop in pressure in a test section over a period of time.
(b) When testing against closed metal-seated valves, an additional leakage per closed valve of 0.0078 gph/in. of nominal valve size shall be allowed.
(c) When hydrants are in test section, the test shall be made against closed hydrant valves.
(d) No pipe installation will be accepted if the leakage is greater than that determined by the following formula:
L = SD T P
133,200
133,200
Where:
L = Allowable leakage in gallons per hour
S = Length of pipe tested in feet
D = Nominal diameter of the pipe in inches
P = Average test pressure during leakage test in pounds per square inch (gauge)
Allowable Leakage per 1,000 Feet of Pipeline* Nominal Pipe Diameter (In) | ||||||||||||||||
Avg. Test Pressure (psi) | 3 | 4 | 6 | 8 | 10 | 12 | 14 | 16 | 18 | 20 | 24 | 30 | 36 | 42 | 48 | 54 |
Allowable Leakage per 1,000 Feet of Pipeline* Nominal Pipe Diameter (In) | ||||||||||||||||
Avg. Test Pressure (psi) | 3 | 4 | 6 | 8 | 10 | 12 | 14 | 16 | 18 | 20 | 24 | 30 | 36 | 42 | 48 | 54 |
450 | 0.48 | 0.64 | 0.95 | 1.27 | 1.50 | 1.91 | 2.23 | 2.56 | 2.87 | 3.18 | 3.82 | 4.73 | 5.73 | 6.69 | 7.64 | 8.60 |
400 | 0.45 | 0.60 | 0.90 | 1.20 | 1.50 | 1.80 | 2.10 | 2.40 | 2.70 | 3.00 | 3.60 | 4.60 | 5.41 | 6.31 | 7.21 | 8.11 |
350 | 0.42 | 0.56 | 0.84 | 1.12 | 1.40 | 1.69 | 1.97 | 2.25 | 2.53 | 2.81 | 3.37 | 4.21 | 5.06 | 5.90 | 6.74 | 7.58 |
300 | 0.30 | 0.52 | 0.78 | 1.04 | 1.30 | 1.56 | 1.82 | 2.08 | 2.34 | 2.50 | 3.12 | 3.90 | 4.68 | 5.46 | 6.24 | 7.02 |
275 | 0.37 | 0.50 | 0.75 | 1.00 | 1.24 | 1.40 | 1.74 | 1.99 | 2.24 | 2.40 | 2.99 | 3.73 | 4.48 | 5.23 | 5.98 | 6.72 |
250 | 0.36 | 0.47 | 0.71 | 0.95 | 1.19 | 1.42 | 1.56 | 1.90 | 2.14 | 2.37 | 2.85 | 3.56 | 4.27 | 4.99 | 5.70 | 6.41 |
225 | 0.34 | 0.45 | 0.68 | 0.90 | 1.13 | 1.35 | 1.58 | 1.80 | 2.03 | 2.25 | 2.70 | 3.38 | 4.05 | 4.73 | 5.41 | 6.03 |
200 | 0.32 | 0.43 | 0.64 | 0.85 | 1.06 | 1.28 | 1.48 | 1.70 | 1.91 | 2.12 | 2.55 | 3.19 | 3.82 | 4.48 | 5.09 | 5.73 |
175 | 0.30 | 0.40 | 0.59 | 0.80 | 0.99 | 1.19 | 1.39 | 1.50 | 1.79 | 1.98 | 2.38 | 2.98 | 3.68 | 4.17 | 4.77 | 5.36 |
150 | 0.28 | 0.37 | 0.55 | 0.74 | 0.92 | 1.10 | 1.29 | 1.47 | 1.56 | 1.84 | 2.21 | 2.76 | 3.31 | 3.86 | 4.41 | 4.97 |
125 | 0.25 | 0.34 | 0.50 | 0.87 | 0.84 | 1.01 | 1.18 | 1.34 | 1.51 | 1.68 | 2.01 | 2.52 | 3.02 | 3.53 | 4.03 | 4.53 |
100 | 0.23 | 0.30 | 0.45 | 0.60 | 0.75 | 0.90 | 1.05 | 1.20 | 1.35 | 1.60 | 1.80 | 2.25 | 2.70 | 3.15 | 3.60 | 4.05 |
* If the pipe being tested contains sections of various diameters, the allowable leakage will be the sum of the computed leakage for each size. To obtain leakages in liter/hour, multiply the values in the table by 3.785.
| ||||||||||||||||
(4) Acceptance of testing. If test results disclose leakage greater than allowable limits, the contractor shall, at his or her own expense, locate and make approved repairs as necessary until the leakage is within the specified allowance. Additional tests performed after the repairs will be at the contractor’s expense. All visible leaks are to be repaired, regardless of the amount of leakage.
(5) Disinfection of system. After construction is complete, the newly installed system shall be flushed to remove dirt and foreign material. The lines shall then be disinfected in accordance with procedures outlined by the American Water Works Association Standard AWWA C651.
(6) Chlorinating requirements.
(a) Water shall be supplied to the new system at a constant, measured rate. In the absence of a meter, the rate may be approximated by methods such as placing a Pitot gauge in the discharge and measuring the time to fill a container of known volume.
(b) At a point not more than ten feet downstream from the beginning of the new main, water entering the new main shall receive a dose of chlorine fed at a constant rate such that the water will have not less than 50 mg/l free chlorine. To assure that the correct concentration is provided, measure units shall be taken at regular intervals in accordance with the procedures described in the current edition of Standard Methods for the Examination of Water or Wastewater, AWWA Manual M12, or by using an appropriate chlorine test.
(c) The following table lists the amount of chlorine required for each 100 feet for various diameters of pipe. Solutions of 1% chlorine may be prepared with sodium hypochlorite or calcium hypochlorite. A solution using calcium hypochlorite requires one pound per eight gallons of water.
Chlorine Required to Produce 50 mg/l Concentration in 100 Feet of Pipe by Diameter | ||
Pipe Diameter (in) | 100% Chlorine (lb) | 1% Chlorine Solution (gal) |
Chlorine Required to Produce 50 mg/l Concentration in 100 Feet of Pipe by Diameter | ||
Pipe Diameter (in) | 100% Chlorine (lb) | 1% Chlorine Solution (gal) |
4 | 0.026 | 0.32 |
6 | 0.060 | 0.72 |
8 | 0.108 | 1.30 |
10 | 0.170 | 2.04 |
12 | 0.240 | 2.88 |
16 | 0.434 | 5.20 |
(d) While chlorine is being applied, valves shall be positioned so that the strong chlorine solution will not flow into water mains in active service. Chlorine application shall not cease until the entire main is filled with heavily chlorinated water. The chlorinated water shall be retained in the main for at least 24 hours. During this time, all valves and hydrants in the section being treated shall be operated to ensure disinfection of all appurtenances. At the end of this period, the treated water in all portions of the main shall have a residual of not less than ten mg/l free chlorine.
(7) Flushing.
(a) After the applicable testing period, heavily chlorinated water shall be removed in order to prevent damage to the pipe. The chlorinated water shall be flushed from the main until chlorine measurements show that the concentration in the water leaving the main is greater than 0.5 mg/l but less than 2.0 mg/l.
(b) Chlorinated water shall be properly discharged to an approved sanitary sewer. If no sanitary sewer is available, a reducing agent shall be applied to the water to be wasted in order to thoroughly neutralize the residual. The following table shows the amount of neutralizing chemicals required. Where necessary, federal, state and local regulatory agencies should be contacted to determine if there are special provisions for the disposal of heavily chlorinated water.
Pounds of Chemicals Required to Neutralize Various Residual Chlorine Concentrations in 100,000 Gallons of Water* | ||||
Residual Chlorine Concentration (mg/l) | Sulfur Dioxide (SO2) | Sodium Bisulfate (NaHSO3) | Sodium Sulfite (Na2SO3) | Sodium Thiosulfate (Na2S2O35H2O) |
1 | 0.8 | 1.2 | 1.4 | 1.2 |
2 | 1.7 | 2.5 | 2.9 | 2.4 |
10 | 8.3 | 12.5 | 14.6 | 12.0 |
50 | 41.7 | 62.6 | 73.3 | 60.0 |
* Except for residual chlorine concentration, all amounts are in pounds.
| ||||
(8) Bacteriological test.
(a) Satisfactory bacteriological test results approved by the Indiana State Board of Health shall be produced for two successive sets of samples, collected at 24-hour intervals, before the new mains are accepted for use. A copy of the test results shall be provided to the town.
(b) The contractor shall notify the town when the system and disinfection is complete and the water is ready for bacteriological testing. The town representative must be present when the contractor collects the sample. The contractor must submit the sample to an independent certified laboratory for bacteriological analysis at the contractor’s expense.
(c) Samples shall be collected from the end of the line and tested for bacteriological quality in accordance with Standard Methods for the Examination of Water and Wastewater. At least one set of samples shall be collected from the new main and one from each branch. In long mains, samples shall be collected along the length of the line, at reasonable intervals, as well as at its end. Samples for bacteriological analysis shall be collected in sterile bottles treated with sodium thiosulfate. No hose or fire hydrant shall be used in the collection of samples.
(9) Re-testing and disinfection. If the test results are unsatisfactory, the contractor shall re- flush the lines and repeat the disinfection. Testing shall be repeated as noted above until the testing results are satisfactory and the mains are approved for service.
(Ord. 2019-8-26(A), passed 8-26-2019)