(A) General.
(1) This section describes the minimum requirements and general procedures for the inspection and testing of domestic water systems to be dedicated to the town.
(2) Water systems shall not be accepted nor will connection permits be issued until all requirements for inspection and testing, including the filing of affidavits and any other paperwork are completed. The contractor is responsible for notifying applicable utilities prior to construction to request locating services and verify utility locations.
(3) Any section of infra-structure not passing the tests prescribed herein shall be repaired to the satisfaction and approval of the town, and then retested and reinspected at the owner’s expense.
(B) Inspection cost and fees. Inspection of the construction shall occur throughout installation of the system and prior to the backfilling of the utilities.
(1) General. Prior to the issuance of a construction permit and the commencement of construction, the owner shall make arrangements with the town, and the county, if applicable, for construction inspection services to be provided.
(2) Estimated cost.
(a) If inspector services are required by the town, a letter shall be sent to the owner, stating the estimated amount of payment for inspection services to be rendered by representatives of the town. The amount provided in the letter shall be 75% of the total estimated cost of the inspection services based on an estimated project completion time and approved construction plans. The owner shall be responsible for fees associated with the county independently. Where a pumping station is involved, additional time for the inspection during construction and final checkout of the station shall be added.
(b) The inspection cost is a pre-construction estimate only. The actual observation time will vary from project to project and may exceed or be less than this estimate based upon actual project duration. Observation time at the site is verified by the contractor and/or a representative of the owner. Deviations from approved construction documents or owner established schedules that create the necessity of additional inspection, shall be at the owner’s expense.
(c) Seventy-five percent of the cost shall be remitted prior to issuance of a construction permit. The balance of the cost for observation services, based on total actual observation hours, shall be paid prior to the town’s acceptance of the system.
(3) Inspection scheduling.
(a) The contractor and/or owner shall provide notice to the town of the planned commencement of construction at least two weeks prior to such commencement.
(b) Once the construction starts, the contractor shall be responsible for informing and/or notifying the Inspector assigned of the following:
1. Daily work schedule including any changes in schedule;
2. Prior notification if work is to be performed on weekends and/or holidays;
3. Date tests are to be performed; and
4. Date as-built verification is to be performed.
(c) The town, upon written request of the contractor and/or owner, will schedule the final inspection.
(d) All testing required shall be performed under the observation of the town’s and/or the county’s inspector(s). It shall be the contractor’s responsibility to schedule the testing with the inspection(s). Test results obtained in the absence of the presence of the town’s representative will not be accepted.
(4) Inspection of service connections.
(a) A connection permit shall be obtained for any repair, modification or connection of a building sewer or water line to a public utility. Connection permits shall not be issued for connections to sanitary sewers or water distribution systems not yet dedicated to and accepted by the town.
(b) Following the installation/repair/modification and prior to the backfilling of the service line, the contractor/plumber shall notify the town that the service line is ready to be inspected. The town shall then have 24 hours to make the inspection after which the contractor/plumber may backfill the trench. Inspections requested on Fridays or on a day proceeding a holiday may not be completed until the next normal business day.
(c) If notification is not provided and the building sewer is backfilled prior to inspection, at the town’s request the contractor/plumber shall be required to re-excavate the trench so that an inspection can be made.
(d) Protection of open trenches and compliance with applicable OSHA Standards is the responsibility of the contractor/plumber.
(5) Final grade. Manholes, water meters, fire hydrants and the like shall be properly set at final grade. Costs associated with raising or lowering due to grade changes will be charged to the contractor.
(C) Domestic watermain disinfection and testing.
(1) All domestic water lines will be pressure tested with the town’s inspector present. The owner/contractor shall notify the town’s Water Department at least 72 hours in advance of testing. The contractor shall provide all equipment necessary for the testing.
(2) Each section of pipe shall pass a pressure and leakage test in accordance with the most recent requirements of AWWA Standard C600-93, § 4.1, Pressure and Leakage Test.
(3) Thrust blocks, if used, shall have been in place for not less than ten days prior to testing lines.
(a) Test restrictions.
1. Test pressure shall not be less than one and one-half times the working pressure at the lowest point along the test section, or 100 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.
2. 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.
3. Test pressure shall not exceed the rated pressure of the valves when the pressure boundary of the test section included closed, resilient-seated gate valves, or butterfly valves. No test sections shall exceed five miles in length without prior approval from the Engineer.
(b) Test procedures.
1. 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. 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.
2. 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.
3. All exposed pipe, fittings, valves, hydrants and joints shall be examined carefully during the test. Any damaged components during or after the pressure test shall be repaired at the contractors expense. The test shall be repeated until the results are satisfactory to the town.
(c) Allowable leakage.
1. 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 five 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.
2. No pipe installation will be accepted if the leakage is greater than that determined by the following formula:
L - SD T V 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)
To View This Table as a PDF document CLICK HERE
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 | 4.78 | 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 | 2.31 | 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 | 0.50 | 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 pipeline under test contains sections of various diameters, the allowable leakage will be the sum of the computed leakage for each size | ||||||||||||||||
3. 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.
4. When hydrants are in test section, the test shall be made against closed hydrant valves.
(d) 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.
(e) 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.
(f) Chlorinating requirements.
1. 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.
2. 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.
3. 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 | 0.06 | 0.72 |
8 | 0.108 | 1.30 |
10 | 0.17 | 2.04 |
12 | 0.24 | 2.88 |
16 | 0.434 | 5.2 |
4. 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 than ten mg/l free chlorine.
(g) Flushing.
1. 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.
2. Chlorinated water shall be properly discharge to an approved sanitary sewer. If no sanitary sewer is available, a reducing agent shall be applied to the water to be waste in order to thoroughly neutralize 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.
(h) Bateriological test.
1. Satisfactory bacteriological test results approved by the 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.
2. The contractor shall notify the town when the system and disinfection is complete and the water is ready for bacteriological testing. The town representative will then collect the sample with the contractor present. The town will submit the sample to an independent certified laboratory for bacteriological analysis at the contractor’s expense.
3. 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 case of 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.
(i) Re-testing and disinfection. If test results are unsatisfactory, the contractor shall reflush 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
(D) Manhole testing and inspection.
(1) Each manhole shall be visually inspected for leakage or evidence thereof. If the manhole shows leakage the manhole shall be repaired to the satisfaction of the town, and re-inspected, and re-tested at the contractor’s expense.
(2) Manholes will be checked by the town after installation and again before the one-year warranty period ends. If manholes show signs of leakage, they shall be vacuum tested by an approved company and repaired at the contractor’s expense.
(3) The contractor shall test all manholes using the Standard Test Method for Concrete Sewer Manholes by the Negative Air pressure (Vacuum) Test.
(a) Scope.
1. This section covers procedures for testing precast concrete manhole sections using the vacuum test method to demonstrate the integrity of the installed materials and the construction procedures. This test method is used for testing concrete manhole sections utilizing mortar, mastic or gasketed joints and is intended to be used as a preliminary test to enable the contractor to demonstrate the condition of the concrete manholes prior to backfill. It may also be used to test manholes after backfilling; however, contractor must correlate the testing with the connector supplier.
2. This test method is the companion to metric Test Method C 1244M; therefore, no SI equivalents are shown in this test method.
(b) Reference documents.
1. ASTM Standards;
2. C822, Terminology Relating to Concrete Pipe and Related Products/2;
3. C924, Practice for Testing Concrete Pipe Sewer Lines by Low-pressure Air Test Method/2;
4. C969, Practice for Infiltration and Exfiltration Acceptance Testing of Installed Precast Concrete Pipe Sewer Lines/2; and
5. This practice is under the jurisdiction of ASTM C-13 on Concrete Pipe, most recent edition.
(c) Procedures.
1. All lift holes and any pipes entering the manholes are to be plugged. A vacuum will then be drawn and the vacuum drop over a specified time period will be used to determine the acceptability of the manhole.
2. The test head shall be placed at the top of the manhole in accordance with the manufacturer’s recommendations.
3. A vacuum of ten inches of mercury shall be drawn on the manhole, the valve on the vacuum line of the test head will be closed, and the vacuum pump shut off. The time shall be measured for the vacuum to drop to nine inches of mercury.
4. The manhole shall be considered to pass if the time for the vacuum reading to drop from ten inches of mercury to nine inches of mercury meets or exceeds the values indicated.
5. If the manhole fails the initial test, necessary repairs shall be made using an approved method. The manhole shall then be re-tested until a satisfactory test result is obtained.
6. Use or failure of this vacuum test shall not preclude acceptance by appropriate water infiltration or exfiltration testing if approved by the town.
(Ord. passed - -)