“Lift and Shift” method covers 150 miles of mains with only 12 sensors
Milford, Ohio (July 24, 2013) – The Holly Springs Public Works Department (Holly Springs, N.C.) used leak detection equipment from Fluid Conservation Systems to improve the efficiency and response time of its municipal water leak detection program.
Holly Springs Public Works is responsible for maintaining 150 miles of mains to service the town’s 11,000 connections. In the spring of 2011, workers began noticing evidence of underground water leaks. With only a ground microphone at their disposal, they were finding it difficult to locate the leaks without extensive exploratory digging and realized the need to upgrade leak detection equipment. The Holly Springs Public Works Department approached Ron Lilley of Carolina Meter (Hampstead, N.C.), who provided a demonstration of Fluid Conservation Systems equipment.
“We purchased the equipment and began using it the following year. We found 12 leaks within the first few months, including hydrants and blow offs that weren’t tightened all the way,” said Holly Springs Public Works Technician, Steve Wenz.
Holly Springs purchased 12 FCS Permalog leak noise sensors, a Tri-Corr leak noise correlator and an X-Mic ground microphone. Permalogs attach magnetically to pipelines and “listen” for leak noise signatures during nighttime hours when ambient noise is at its lowest. The Tri-Corr correlator then analyzes data from the Permalogs to identify and give the approximate location of a leak, which can then be pinpointed using the X-Mic ground microphone.
To maximize efficiency, Holly Springs uses the “Lift and Shift” method where Permalogs are deployed in one area, then data is collected and the sensors are quickly redeployed to another area. This allows the town’s 12 sensors to monitor all 150 miles of mains.
“In one case, we used the FCS equipment to pinpoint a leak that was surfacing in a cul-de-sac over 100 feet downhill from the actual leak,” said Wenz. “Without the equipment, we never would’ve found the leak without a great deal of costly digging.”