360 CMR, § 12.06

Current through Register 1533, October 25, 2024

Section 12.06 - Methods

Sonic leak surveys shall be required for all underground pipe. Visual inspection of tanks, reservoirs and above ground pipe is acceptable. The following general procedures shall be followed:

(1) Available points of direct contact to the distribution piping system shall be sounded, including valves, hydrants and selected sidewalk service connections.

(2) Inpaved roadways, a ground microphone shall be used to listen over the pipeline at intervals not to exceed ten feet.

(3) In unpaved areas, a pattern of listening points shall be established to ensure complete coverage.

(4) Indications of leakage shall be investigated immediately and shall be pinpointed to the most probable point of leakage, with location clearly marked by an acceptable method such as paint on pavement or stake in earth and reference measurements to a permanent structure taken.

(5) The leak shall be classified as to estimated water loss and severity. A leakage site report shall be prepared for each suspected point of leakage.

If leakage potential is less than 10%, the sounding of only direct contacts such as hydrants is allowable with use of ground microphones for pinpointing only. District measurement shall also constitute an appropriate method of leakage investigation. If the community demonstrates through district measurement that all or a portion of the municipal distribution system has a low ratio of minimum night rate to total consumption, the sounding of only direct contacts such as hydrants for the applicable districts will be allowed; if the ratio is greater than 40% and cannot be attributed to industrial use at night, such districts shall be investigated by a full sonic survey.

360 CMR, § 12.06