Marion County experienced higher than normal non-revenue water (NRW) loss in specific zones of its distribution system. However, the utility could find no visible water leakage. The county commissioned McKim & Creed to conduct an acoustic leak detection investigation.
Using manual sounding techniques, McKim & Creed detected a leak in a main PVC line. This line was losing a conservative estimate of 28,800 gallons of non-revenue water per day. Investigators conducted further pinpointing and confirmation with a ground microphone. This showed that the leak was at or near the cross-section of an intersection in a residential community. Although the leak was surrounded by sand and the pipe was only about five feet deep, there were no visible signs of the leak at the surface level. The utility quickly repaired the link, saving thousands of gallons of NRW per day.
This leak detection investigation project is one of many that proves that NRW leaks do not always surface, even if the pipes are shallow and buried in sandy substrate.