Millions of Gallons of Water Lost Through Leaks, Other Sources
Posted December 18, 2007
Durham, N.C. — As Raleigh and Durham tighten the taps on residential and business users to conserve water in the midst of a record-setting drought, the two municipal systems continue to lose millions of gallons daily through leaky pipes and other sources.
Water has steadily bubbled into Broad Street outside Dr. Deb Conner's endodontics office in downtown Durham for weeks from an underground pipe. A stream of water flows down the gutter into a nearby storm drain.
"Over 24 hours a day for four to six weeks is significant," Conner said. "Someone did come and looked at the problem and recognized, yes, it is leaking. They tried to find the source but were unable to."
Such leaks are just a part of the reason the city loses nearly 13 percent of its average daily water consumption, or about 2.6 million gallons each day.
"The 11 percent to 13 percent ... is our 'unaccounted-for-water' and is not strictly attributable to leaks in the system," Vicki Westbrook, deputy director of Water Management for Durham, wrote in an e-mail to WRAL Tuesday.
Durham also makes "educated estimates on the amount of water lost in a main break, the amount of water used to flush a sewer spill, the amount of water used for fire fighting by both the City and volunteer Fired Departments, the amount of water used for street sweeping and cleaning, sewer line flushing . . . and the list goes on," she wrote.
Durham had "an extensive leak detection survey" a few years ago and that report showed only minor leaks in the system, which were addressed, she said. After the first of the year, Durham will contract out another leak detection survey.
Westbrook said it should also be noted that "the extremely dry weather is a direct cause of many leaks; as the ground dries and contracts, pipes underground shift, which can lead to both leaks at joints as well as longitudinal leaks."
Water systems in North Carolina are allowed to lose up to 15 percent of their water through leaks and other means under state rules.
About 8 percent of the 40 million gallons Raleigh pumps through its system every day – 3.2 million gallons – cannot be accounted for. So, the city has assigned a team of workers to track and fix leaks as soon as possible.
"If it's leaking, it gets fixed right away," team member Dennis James said.
The team inspects 2,000 miles of underground water pipes in Raleigh, using $45,000 audio sensors that work like high-powered stethoscopes to hear leaks.
Raleigh officials said Tuesday that tougher water restrictions could be enacted after Christmas. About 95 days of drinking water remain in Falls Lake, the city's primary reservoir.
"If I find a leak, that's a good feeling," James said. "Anything you accomplish, you feel good about it."
Conner said she wishes Durham had a similar program to plug the leak outside her office.
"We are trying to be frugal and responsible citizens with this kind of water shortage, and we want the city to rise to the same standards," she said.