South Lake Tahoe, California
Like a growing number of U.S. communities, South Lake Tahoe has a problem with MTBE (methyl tertiary butyl ether), a gasoline additive that causes cancer in lab animals. Tests in the 1990s confirmed that MTBE had seeped out of local storage tanks and contaminated the groundwater, closing one-third of the city's wells. South Lake Tahoe sued 31 oil companies, gas stations, and MTBE manufacturers, who are now footing a $69 million cleanup bill. The work will take decades to complete.
Lead levels in Boston's water, high throughout the 1990s, surpassed recommended levels in 2001. Filtration, which eliminates disease-carrying microorganisms, is also an issue. Boston claims its watersheds are clean enough that it shouldn't have to filter its municipal water before sending it to taps. The EPA disagrees, but it lost a 1998 lawsuit that would have forced the city to augment its current chlorine-based disinfection system.
More than 1,400 potential pollution sources, including 558 hazardous-waste facilities, 121 industrial sites, and 14 mines, threaten the health of the Upper Chattahoochee watershed, the primary source of Atlanta's drinking water. The city has a century-old water system in need of modernization, and residents have reported muddy, discolored tap water over the past four years.
Philadelphia's drinking water comes from the Schuylkill and Delaware rivers, which are contaminated by pesticides and industrial chemicals. But pollution controls in the watersheds, governed mainly by the state of Pennsylvania, are "incomplete at best," warns the NRDC. Lead, which enters water supplies via corroded pipes, is such a concern that, in October 2000, some city schools began serving bottled water to students.
Rancho Cordova, California
Up to 20 million Americans may be drinking tap water containing perchlorate, a toxic ingredient in rocket fuel. From the 1950s through the 1980s, fuel used at Rancho Cordova's Aerojet rocket-engine plant seeped into the groundwater; contaminated wells continue to be discovered. Cleanup of the ten-square-mile underground perchlorate plume at Rancho Cordova, funded by Aerojet, will cost more than $111 millionand take an estimated 240 years to complete.
Phoenix tap water, which comes mostly from the Colorado, Salt, and Verde rivers, has in recent years contained unacceptably high levels of chlorination by-products and DEHP, an industrial chemical that causes liver damage. In 2000, perchlorate, a toxic chemical that disrupts thyroid function and is a suspected carcinogen, was also detected. Phoenix has been less than forthcoming with its citizens: In 2000, the city paid the EPA and the state of Arizona $350,000 for numerous reporting and monitoring violations.
Urban runoff and pesticides from farms in California's Central Valley taint Fresno's watersheds. As a result, in 2000 and 2001 the city's drinking water contained nitrates, radon, pesticides, and industrial chemicals at levels the NRDC calls a "serious concern." With nitrate levels spiking above national maximums those same years, pregnant women were advised to consult their doctors before drinking Fresno's tap water.
Albuquerque, New Mexico
Arsenic levels in Albuquerque's tap water are some of the highest in any major U.S. city. The naturally occurring element was found at an average level of 14 parts per billion in 2001under the current limit of 50 ppb but exceeding the ten-ppb limit that goes into effect in 2006. The city expects to spend at least $30 million on new systems to keep its water in compliance.
The capital's drinking water isn't winning any purity awards. Levels of coliform, a bacteria associated with the presence of disease-causing organisms, nearly tripled between 1999 and 2001. Lead content approached the EPA's maximum limits in 1999 and 2000. While still found at relatively high levels, chlorination by-products (associated with cancer and birth defects) have decreased in Washington's water, thanks to new disinfection strategies.
Houston reports water with levels of radioactive radon averaging 700 picocuries per litermore than double the EPA's proposed maximum of 300 pCi/L. (Radon, a naturally occurring gas, has been proven to cause lung cancer.) Trihalomethanesby-products of chlorine disinfectionspiked to levels 1.5 times the national standard in 2001. Pesticides from upstream farms and urban runoff also threaten the city's chief drinking-water sources, the San Jacinto and Trinity rivers.