While on a worldwide investigation of dirty drinking water -- with stops in Bangladesh, Uruguay and Namibia -- a United Nations investigator visited the Tulare County community of Seville in March. After seeing conditions, the investigator urged state and federal authorities to consider healthy drinking water a human right and clean up the mess.

In a state with the world's seventh-largest economy, it wouldn't take a lot of money to clean up the Valley's small-town water problems -- $150 million total for projects on record. San Francisco last year committed the same amount of money to help homeowners and businesses finance solar panels and water efficiency.

But small-town residents face an uphill fight for the healthy drinking water that most Californians take for granted. Townfolk feel they have nowhere to turn. State public health authorities make a habit of inviting them to apply for cleanup funding, then turning them down for technicalities.

Residents, activists, engineers and local officials say the Valley's small drinking water systems are barely a blip on the state's radar.

They are not alone in shouldering an extra cost for water. Last year, 95% of the people in a survey of small water systems in Tulare County said they drink bottled water or purified water sold from a machine. The Pacific Institute, an Oakland-based nonprofit group, did the survey as a part of a report on the human cost of nitrates in the drinking water.

The survey results showed some people spend more than 10% of their income to buy water for their families, though the U.S. Environmental Protection Agency in the 1990s said 1.5% would be a better guideline.