Study Finds Peril in Water Supply : Safety: About 14% of U.S. population drinks from systems that have violated federal contamination standards in last three years, researchers say.

The drinking water of more than 36 million Americans, about 14% of the nation’s population, comes from water systems that have reported unsafe levels of contamination during the past three years, according to a study released Wednesday by an environmental group, the Natural Resources Defense Council.

Based on data collected by the federal Environmental Protection Agency in 1992 and 1993, the study lists California with the most people--2.8 million--who are dependent on drinking water systems that registered contamination levels in excess of federal safe drinking water standards.

The report’s authors arrived at the 36 million figure by adding up the number of people served by water systems found to be in violation of EPA contamination limits.

The study also says that about 50 million people, including 16 million Californians, depend on drinking water systems that failed to comply with all federal water quality regulations in effect in 1992 and 1993. Noncompliance increases the chance of contamination. The regulations require systems to protect watersheds from microbiological contamination and to make systems less corrosive in order to prevent lead from leaching into tap water.

“Most drinking water systems comply with federal requirements, but today’s report shows that there is still cause for concern,” said EPA Administrator Carol M. Browner. “Too many systems fail to meet basic public health standards.”

The study does not say how many people got sick as a result of drinking contaminated water. The author of the study, NRDC attorney Erik Olson, cited a report by the Centers for Disease Control estimating that 900,000 people a year are made sick by inadequately treated drinking water.

According to Olson’s report, the most common types of contamination showing up in poorly treated water include microorganisms such as cryptosporidium, which was responsible for the outbreak of intestinal illness that affected 400,000 Milwaukee residents last year. Other contaminants cited by Olson range from pesticides and industrial solvents to toxic byproducts of the chlorine used to purify most drinking water systems.

Olson said that the widespread evidence of contamination reflects “a gross under-investment in treatment facilities in most big cities.” According to the NRDC’s report, “90% of the nation’s large water utilities are using pre-World War I water treatment technology.”

These facilities, he said, fail to catch a variety of chemical contaminants as well as microorganisms. The antiquated facilities, Olson said, rely on sand filtration supplemented by chlorine purification. High levels of chlorine byproducts, called trihalomethanes, have been detected in people with rectal and bladder cancer, he noted.

The NRDC released its study in the midst of a congressional battle over proposed changes to the Safe Drinking Water Act. The NRDC and most other environmental groups argue that a coalition of municipal water agencies, which includes the Metropolitan Water District of Southern California, is trying to soft-pedal the contamination problem while it works to weaken the Safe Drinking Water Act.

“Some of the same people who have kept from the public full knowledge of the extent of contamination are now mounting efforts to weaken the law that protects the public’s health,” Olson states in the introduction of the NRDC study.

Proponents of the legislation argue that they are proposing the most cost-effective ways for municipal water systems to make the most-needed improvements, and they accuse the NRDC, in its report, of making EPA data look worse than it is.

“This is a tactic to whip up public support by one side of a legislative contest,” said Bruce Kuebler, director of water quality for the Los Angeles Department of Water and Power.

Kuebler said that his department is “technically” in violation of the act because it is late in complying with a 1993 regulation requiring additional treatment of water stored in exposed reservoirs.

“Complying is going to take us 10 years and cost several hundred million dollars,” Kuebler said. “So, sure, you can say that’s a violation. But it doesn’t mean people are drinking contaminated water.”

Charles Fox, director of policy development at the EPA’s Office of Water, said that Kuebler has a point.

“A violation doesn’t necessarily translate into a threat to the public’s health,” Fox said. But he also said that, in general, the NRDC is not making too much out of the violations compiled by EPA.

“It is fair to say that the violations are indicative, in many cases, of a certain public health standard not being met,” he said. “With a reported violation, a system is often saying, ‘We don’t have in place the facilities that can consistently provide the public the protection required under the law.’ ”