§ 152.17 EXECUTION.

   (A)   General construction requirements.

      (1)   Before installing piping, the contractor shall carefully verify location, depth, type of joint needed, and size of pipe to which connection is proposed. Contractor shall assure that the lines can be run as contemplated without interfering with footings, walls, other piping, fixtures, and the like.

      (2)   All lengths of pipe shall be dimensioned accurately to measurements established at the site and shall be worked into place without springing or forcing. Cut sections of pipe shall be reamed to remove all burrs.

      (3)   Utmost care shall be exercised in transporting and handling all pipe, fittings, valves, and the like, in order to avoid shock and damage to pipe coatings. Lifting shall be by hoist or skids when hand lifting is not feasible. Droppings will not be permitted. Pipe handled on skid ways must not be skidded or rolled against pipe already on the ground. Damaged or defective pipe and appurtenances shall be replaced.

      (4)   The pipe shall be thoroughly cleaned before being laid and kept clean during construction.

      (5)   The contractor shall cut all pipe and drill all holes that may be necessary.

   (B)   Pipe laying.

      (1)   The laying of pipe on the prepared bedding material shall commence from the lowest point, with the spigot ends pointing in the direction of flow. All pipes shall be laid true to line and grade. They shall be carefully centered so that when laid, they form a sewer with uniform invert.

      (2)   A pipe plug or bulkhead shall be used whenever pipe-laying operations are not in progress as required to protect the pipe ends from foreign material.

      (3)   Before making pipe joints, all surfaces of the joints shall be clean and dry. Lubricants, primers, and adhesives shall be used in accordance with the manufacturer’s recommendations. The pipe shall then be placed, fitted, and adjoined so as to obtain a watertight joint. In the event that previously laid pipe is disturbed, it shall be removed and re-laid.

      (4)   The contractor shall assure proper alignment and grade by proper use as lasers, batter boards, surveying instruments or other suitable means.

   (C)   Leakage tests.

      (1)   Generally. Prior to acceptance, all gravity sewers and manholes, including service laterals, shall be tested and pass a test for leakage. The contractor shall furnish all labor, materials, and equipment required for making the tests and groundwater level determinations. Testing shall not be performed until backfilling and compaction are completed. All gravity sewers shall pass one of the three following leakage tests as further specified by this section.

         (a)   Low pressure air test conforming to the requirements of the latest revision of ASTM C828 and ASTM C924 as minimum. The low pressure air test shall be used unless the contractor approves an infiltration or exfiltration test.

         (b)   Infiltration test with a maximum inward leakage of 100 gallons per inch of pipe diameter per mile per day.

         (c)   Exfiltration test with a maximum outward leakage of 100 gallons per inch of pipe diameter per mile per day. In addition, the contractor shall notify the town at least 48 hours in advance of any leakage tests as required to permit the town to witness such testing. The contractor shall keep documentation of leakage tests and their results with two copies submitted to the town upon completion and passage.

      (2)   Determination of groundwater level.

         (a)   Prior to and during all testing, the contractor shall determine all groundwater levels by backfill groundwater gauges or manhole groundwater gauges. In general, a sufficient number of groundwater gauges shall be installed to determine groundwater levels in the area of sewers being tested.

         (b)   In the case of newly installed groundwater gauges or the attachment of the temporary clear plastic tubing in the manhole groundwater gauge, the level of groundwater shall be allowed to stabilize before determining the groundwater level.

      (3)   Pipeline testing.

         (a)   Low pressure air test. Immediately prior to testing, the pipe shall be cleaned. After cleaning, all pipe outlets shall be plugged. The contractor must be aware that low pressure air testing may be dangerous. The contractor shall review the paragraphs entitled “Safety Precautions” in ASTM C828 and ASTM C924 before beginning pressurization of pipe. The sewer line shall then be slowly pressurized of 4.0 psig greater than the hydrostatic pressure head created by any groundwater over the pipe (i.e., the height of the groundwater above the invert of pipe, in feet, multiplied by 0.43). Where such internal pressure adjustment would result in a starting pressure greater than 9.0 psig, an infiltration test shall be performed. The method of pressurizing shall be such that the pressure shall be maintained until the temperature of the pipe and the air have equalized but in no case less than five minutes. After the temperature has stabilized, the air supply shall be discontinued and the pressure allowed to drop. When the pressure reached 3.5 psig (not including additional air pressure required by groundwater), a stopwatch shall be used to record the time it takes for the pressure to drop to 2.5 psig (or a one pound pressure drop). If the recorded time is more than the minimum test time as computed using Table 1 below, the section of pipe shall be considered to have passed the leakage test. If the recorded time is less than the minimum test time, the line shall be considered to have failed the test, shall be inspected for possible leaks, and retested upon correction until such time as the line passes the requirements.

Table 1 Low Pressure Air Test Minimum Test Time for Pressure to Drop from 3.5 to 2.5 PSIG
Nominal Pipe Diameter, Inches	Minimum Test Time, Minutes per 100 Feet
4	0.3
6	0.7
8	1.2
10	1.5
12	1.8
15	2.1
18	2.4
21	3.0
24	3.6
27	4.2
30	4.8
33	5.4
36	6.0
39	6.6
42	7.3

 

         (b)   Infiltration test.

            1.   An infiltration test shall be used only when approved by the town or when the starting pressure for the low pressure air test would be greater than 9.0 psig. For an infiltration test to be performed, the ground water elevation must be at least 2.0 feet above the crown of the upstream pipe. The test shall require cleaning of the line and then plugging the pipe opening with a watertight plug with length equal to or greater than the pipe diameter.

            2.   A 90-degree V-notch weir shall be placed in the downstairs manhole of the section of pipe being tested. When performing an infiltration test with a weir, sufficient time will be allowed for the infiltration to crest the weir and stabilize. This time shall be determined based on the size of the sewer line, the slope of the line, and other pertinent information. In no case shall the time be less than one hour. The contractor shall measure the head (H) of water flowing over the weir. The measurement must be accurate and taken a minimum distance of 18 inches or four times the height of H upstream of the weir, whichever is greater. The measured infiltration over the weir can be calculated as: Q = 3204 H to the power of 2.5. Where H is inches and Q is gallons per day.

            3.   Where the infiltration allowances are very small, the measurement by weir inaccurate, the leakage measurement shall be made by timing the filling of a container of blown volume; The volume collected shall be converted to a 24-hour basis for comparison with specification requirements. If the measured infiltration is less than that allowed by Table 2 below, the pipe section shall be considered to have passed the leakage test.

Table 2 Infiltration and Exfiltration Tests Allowable Infiltration or Exfiltration Based on 100 Gallons per Day per Inch of Pipe Diameter per Mile of Pipe
Sewer Pipe Requirements
Nominal Pipe Diameter, Inches	Allowable Infiltration Gallons Per Foot of Pipe Per Hour
4	0.0032
6	0.0047
8	0.0063
10	0.0079
12	0.0095
15	0.0118
18	0.0142
21	0.0166
24	0.0189
27	0.0237
30	0.0237
36	0.0284
42	0.0331
48	0.0379

 

 

Manhole Requirements
Nominal Manhole Diameter, Inches	Allowable Infiltration/Exfiltration, Gallons per Vertical Foot per Hour
48	0.0379
60	0.0473
72	0.0568

 

         (c)   Exfiliration test.

            1.   An exfiltration test may only be performed in lieu of a low-pressure air test only as approved by the town.

            2.   Before beginning the exfiltration test, the pipe shall be cleaned. Once cleaned, the downstream pipe outlet shall be sealed at the manhole with a watertight plug. To assure a proper seal, the plug shall be at least equal to the diameter of the pipe being tested. (Note that if service laterals were connected, any opening lower in elevation than the static water level will also have to be plugged.)

            3.   The upstream manhole shall be filled with water to a static level not lower than four feet above the top of the sewer pipe (at its highest point) and not less than four feet higher than the existing groundwater table, whichever is greater. In lieu of using the upstream manhole, a standpipe can be used to develop the specific pressure head.

            4.   The water shall be allowed to stand for a period long enough to allow water absorption into the pipe (a minimum of six hours). After the absorption period, the pipe shall be refilled to the established level and the test begun. After a one-hour period, the exfiltration volume shall be calculated by either measuring the drop of water leveling the manhole or measuring the level in the manhole or measuring the volume of water to refill the standpipe to the original level, whichever applies. The measured exfiltration rate shall then be calculated and compared with the allowed by Table 2, the pipe tests, failure to meet the required limits will require correction, repair, and retesting the line.

   (D)   Deflection testing.

      (1)   Deflection testing shall be performed by the contractor in the presence of the town or its representative on all plastic pipes with nominal inside diameters of six inches or greater. Deflection testing shall be accomplished using on of the following devices: calibrated television or photography, or a properly sized “go no go” mandrel or sewer ball. Deflections of no more than 5% based on the base inside the diameters shown below will be allowed:

Table 1: Allowable Deflection
Nominal Size, Inches	Base Inside Diameter, Inches	5% Deflection Mandrel, Inches
6	5.742*	5.45
8	7.665*	7.28
10	9.563*	9.08
12	11.361*	10.79
15	13.898*	13.20
18	16.976**	16.13
21	20.004**	19.00
24	33.480**	21.36
27	25.327**	24.06
* From Tale 69 of Handbook of PVC Pipe, the Uni-Bell PVC Pipe Association, 1982 and/or Table XI.1 of ASTM Specification D3034. ** From Table 70 of the Handbook of PVC Pipe, the Uni-Bell PVC Pipe Association, 1982.

 

      (2)   The deflection test shall be performed no sooner than 30 days following installation of the pipe (including backfill). Prior to testing, the pipeline shall be thoroughly cleaned.

      (3)   Prior to acceptance, pipes having deflections greater than 5% shall be excavated, rebedded, and/or replaced and retested (successfully)

      (4)   The contractor shall submit deflection test reports to the town within 30 days after the performance of each test. A separate report shall be submitted for each manhole-to-manhole sewer section. This report shall provide all pertinent data regarding the test including, but no limit to, the date of the test, details of the testing device used, diameter of pie, the date installation of the line was completed including backfill, and whether the line passed or failed the test.

(Ord. passed - -)