Issues in Leak Detection（I）

A repair worker locates the source of a water main break.To pinpoint leak location and isolate areas of a pipeline for leak repair, utilities managers need to know valve locations, how valves operate and the condition of those valves. This article looks at why leak detection is critical, explains why valve location and condition assessment is vital and introduces new technologies that can determine the overall condition of water pipelines.

THE WATER SITUATION

The deteriorating condition of the nation’s water infrastructure is well-documented. Findings in the American Water Works Association (AWWA) State of the Industry Report 2011 suggest that water utility budgets will continue to be tight in 2013. That report, which is based on responses from nearly 2,100 water industry professionals, found that only 11% of respondents felt their existing plans will cover infrastructure funding needs and nearly a quarter felt that less than 20% of their needs will be met.

Leaks like this have been making major headlines across the country.

Water leaks and main breaks are steeply increasing in frequency as years of unchecked deterioration take their toll on a water infrastructure that, in places, dates back to the second half of the 19th century.

For example, in February 2011, news outlets reported that Kansas City, MO, experienced 467 main breaks in that one winter—a 73% increase from 2010. Montgomery and Prince George’s Counties in Maryland also made news headlines that year for major breaks in their water systems, which deliver service to 1.8 million people. Both counties set a record in December 2010 for having the largest number of water main breaks in a single month—647. The very next month, Prince George’s County experienced a 54-inch water main break that leaked an estimated 50 million gallons of water. These kinds of stories show why 15-30% of treated potable water that is lost—is lost through leaks.

The nation’s water infrastructure is feeling its age and the lack of sufficient funding.In addition to these high profile water main breaks, recent studies by American Water indicate that the average leak runs undetected for more than six months before it surfaces. Leaks on larger transmission mains may never surface, and many instances have occurred where large leaks result when water finds a path of escape, resulting in a problem going undetected until catastrophic failure of a main.