The Environmental Protection Agency's primary tool for ensuring the safety of the nation's drinking water is an impressively massive database containing millions of records on the USA's 170,000 public water systems.

Despite spending six years and $11 million overhauling the database, it still isn't working. And critics say the government's inability to know which water systems are providing dirty water and which are doing well make any attempt to enforce clean-drinking-water laws nearly impossible.

"It's unthinkable that you could have a good enforcement system without a good data system," says James Elder, former director of the EPA's Office of Ground Water and Drinking Water. Elder made the decision in 1991 to overhaul the database, describing the database in place at that time as "not worth its weight in paper." He left at the beginning of 1995 before seeing whether the new system worked.