From the Potomac River and the Goose Creek Reservoir to the beverage glass, the water Loudoun residents drink may contain a small amount of contaminants, as allowed under the Safe Drinking Water Act (SDWA).
"It's striking a balance between what technology can do and what our body and environment can handle," said Samantha Villegas, manager of communications for the Loudoun County Sanitation Authority (LCSA).
Last month, the LCSA released the 2001 Consumer Confidence Report to identify contaminants detected in Loudoun's drinking water and at what levels, compared to the maximum level allowed by the SDWA. LCSA reported meeting the SDWA standards in testing for the presence of bacteria, trihalomethanes, lead and copper in water. The SDWA was passed in 1974 and amended in 1986 and again in 1996.
"Overall, our water is very consistent," Villegas said. "Some things went up a little and some things went down a little, but not enough to be noticeable."
The LCSA reported a slightly higher level of chloroform and of trihalomethanes that still remained within the Environmental Protection Act (EPA) requirements. Trihalomethanes are cancer-causing organic chemicals that result from chlorine reacting with natural organic matter during the water treatment process.
The LCSA conducts water quality testing on a year-round basis and monitors for 12 additional contaminants, including herbicides, pesticides and volatile organic contaminants, as required under the Unregulated Contaminant Monitoring Rule. "We ... own and operate the water delivery system. It's delivered clean to us by the folks that sell it to us, but we still monitor at points throughout the system for its safety and cleanliness," Villegas said.
LCSA's report mentioned two monitoring violations in 2001, which LCSA said did not pose any health threats to Loudoun residents. LCSA collects trihalomethanes on a quarterly basis, but the third quarter samples sent to the state laboratory broke during shipment and were rejected. The second violation was for water quality parameters that assure the water does not cause corrosion to lead solder or copper pipes. LCSA neglected to analyze the parameter locations during one of the monitoring periods.
THE REPORT includes information about the water treatment process, along with LCSA's water sources. LCSA is a wholesale water supplier serving about 48,000 customers in the unincorporated areas of eastern Loudoun with water and waste water services, using water from the Potomac and Goose Creek.
The company purchases water through a contractual agreement with the Fairfax County Water Authority (FCWA), which draws water out of the Potomac River at Lowes Island, and with Fairfax City, which gets its water from the Goose Creek Reservoir near Ashburn. The FCWA and Fairfax City treat the water, which LCSA distributes through a network of transmission mains and 480 miles of distribution lines throughout eastern Loudoun. Residents living in western Loudoun receive their water through the towns or by using private wells.
"We're in a really good situation being that we can get water from two different sources," Villegas said. "We've been very fortunate. The Potomac dipped down in the spring, but it never got to the point to effect our ability ... to meet the demand."
Eastern Loudoun's water demand averages at 11 million gallons a day. Of that, LCSA purchases 6 million gallons from the FCWA and 5 million gallons from Fairfax. The LCSA can purchase up to 27 million gallons a day from the two suppliers.
Water levels in the Goose Creek Reservoir for the past six or seven months have been on a downward trend, still remaining above the historic lows but below the median flow for the past 70 years. "It's nothing out of the ordinary," Villegas said. "We expect it to be low during the summer."
The county is under a precipitation drought with daily averages of stream and ground water levels below normal, as reported in an Aug. 7 county statement.
"For the near term, we have adequate quantities unless there's a severe drought," said Supervisor Chuck Harris (D-Broad Run). "At some point, we're going to have to look at how we use water. ... We have to make sure we are adequately protecting our resources and make sure we have the quantities."
"All along the river, people are taking out water and returning it from ... treatment plants," said Stella Koch, Virginia conservation associate with the Audubon Naturalist Society in Leesburg. "As the number of people increases, you have more demand on the river."
The EPA has required utilities to make the Drinking Water Quality Report available since 1999. The LCSA has provided four annual reports so far.