WATER LEAK DETECTION SURVEYS

DESCRIPTION OF EQUIPMENT: The leak locator we use is an electronic instrument, Model HL90, manufactured by Metrotech Inc., of Sunnydale, California. This device is a self-contained instrument equipped with headphones, sensitivity and gain controls and a ground pick-up. This device is very sensitive to sound and is capable of detecting water leakage of approximately 1/2 gallon per minute. Our company has used this particular leak locator in all our previous leakage surveys and consider this device to be excellent in the field. We are also equipped with a PAL-300 leak correlator, manufactured by Gutermann and Messtechnik of Zolikon, Switzerland, a highly sophisticated leak finder that will pinpoint a leak or leaks that are difficult to locate above ground with our sonic leak detection equipment. In addition, we recently purchased a second correlator, manufactured by Flow Metrix,Inc., of Maynard, MA. This correlator is more advanced, using digital correlating loggers that can be used during the day for short-time correlating or one overnight surveillance. The information retrieved is downloaded onto a laptop computer, where a program analyzes and pinpoints the exact location of the leak. We also are equipped with the necessary tools for conducting the survey such as electronic gate box finders, underground pipe locators, gate and service keys, etc.


LEAK DETECTION SCOPE OF WORK
First we must be provided with a water system map with a up-to-date location of each hydrant and gate valve in the system. Each hydrant and all accessable gate valves are listened to with our leak locator and readings are recorded on the map. Once all the hydrants and gate valves in the system have been recorded, we return to those hydrant and gate valves that had leak sounds. A thorough search in the particular section of the recorded leak is conducted, including listening on service valves, gate valves, and walking directly over the pipeline to pinpoint the leak. The leak correlator will be used if the leak cannot be located by sonic listening equipment. The survey can be conducted during the daylight hours, so that assistance from the Water Dept. is available when needed. A final written report in detail will be submitted upon completion of the survey.

COST FOR LEAKAGE SURVEY
The cost to conduct an entire survey for a particular city or town is based on our manpower and the estimated days and hours needed to complete the survey. Once all the leaks have been located and the necessary repairs made, the result could be a savings of millions of gallons of water costing thousands of dollars annually, thus increasing revenue in the Water Department's budget.