The greatest threat to safe drinking water here and across the country is the web of aging pipes that carry the liquid from treatment plants to taps, according to a microbiologist who researches water for American Water Co.
"Your water can be contaminated right out in the street in front of you," said Dr. Mark LeChevallier, director of innovation and environment stewardship for American Water Co., the parent company of Tennessee-American Water Co.
The United States has one of the safest water supplies in the world. However, national statistics don't tell you specifically about the quality and safety of the water coming out of your tap. To protect yourself:
* Look for your water utility's consumer confidence report at www.epa.gov/safewater/dwinfo.htm.
* Know that water suppliers have 24 hours to inform their customers of violations of EPA standards "that have the potential to have serious adverse effects on human health as a result of short-term exposure."
* Systems will inform customers about violations of less immediate concern in the first water bill sent after the violation, in a Consumer Confidence Report, or by mail within a year.
* EPA compiles and summarizes the state reports into an annual report on the condition of the nation's drinking water.
ON THE WEB
* Watch a trailer of the Penn State Public Broadcasting documentary, "Liquid Assets: The Story of Our Water Infrastructure" at http://liquidassets.psu.edu/
* Read EPA's "Water on Tap" brochure at http://www.epa.gov/safewater/wot/index.html
In the United States, the total miles of drinking water pipeline and aqueducts equal about 1 million miles -- enough to circle the globe 40 times.
"The pipes in many towns were put in 100 years ago. It's not that uncommon to find some sections of pipes are carved out of tree trunks," he said.
When water pipes break, there's potential for far more than just spilled water. Because many pipes carrying fresh, clean water lie in the same ditches, tunnels and infrastructure rights of way as sewer lines, there is great potential for the drinking water to be contaminated.
Government officials increasingly are raising alarms. A June 2009 U.S. Environmental Protection Agency report states 75 percent of the water distribution network's iron-based piping is older than 25 years and about half is older than 50 years.
"There's a $540 billion difference in what we're spending and what's needed" to keep up the nation's 2 million miles of water and wastewater distribution piping, according to Steve Allbee with the EPA's Office of Water.
Kim Dalton, spokeswoman for Tennessee-American Water in Chattanooga, said the company has invested $115 million in infrastructure improvements over the past 13 years.
In May and June, the utility spent about $120,000 replacing about 1,000 feet of pipe near Fifth Street and Central Avenue and another 400 feet of pipe in Lookout Mountain on Lower Cravens Terrace.
In the decade from 1997 to 2007, Dalton Utilities in North Georgia spent $153 million in water system improvements, according to a 2008 online presentation by Chief Executive Officer Don Cope. Much of the money was for wastewater treatment improvements in the Carpet Capital of World, where industrial water use and wastewater are high.
But Mr. Cope's presentation also notes: "Continuing upgrades to distribution system have resulted in annual savings of 700 million gallons of previously unaccounted for water."
The American Society of Civil Engineers in 2009 gave the nation's drinking water infrastructure a D- on the group's annual "America's Infrastructure Report Card."
But that report dealt more with water treatment plants than with piping.
"America's drinking water systems face an annual shortfall of at least $11 billion to replace aging facilities that are near the end of their useful lives and to comply with existing and future federal water regulations," according to the report.
"Leaking pipes lose an estimated 7 billion gallons of clean drinking water a day," the report states.