Veronica Mendoza came to Visalia this morning to pick up a free water filter from the Community Water Center in Visalia.

She’ll put the device on the kitchen faucet at her home in Culter to filter out any DBCP, a now-banned pesticide, from tap water.

“Four to five times a year, I get a notice of DBCP” in the water, Mendoza said in Spanish. “It says there’s nothing to worry about, but if you drink a lot of it, you’ll get cancer. I’ve lived there five years. Each year is a risk.”

Installing water filters on faucets is merely putting “a band-aid” on a larger water contamination problem affecting the San Joaquin Valley, said Laurel Firestone, co-executive director of the Community Water Center. The center was established two years to tackle water contamination issues in rural communities.

This week is National Drinking Water Week, so giving away free filters is a way to alert the public to the scope of the problem, she said.

“Hundreds of community do not have safe drinking water,” Firestone said. “There were 320,000 people in the San Joaquin Valley in 2006 that were served by water systems that had contamination.”

Nitrates are a problem in many wells, but so is arsenic and even percholate.

Protecting groundwater from contamination is the long-term solution, she said.

But so is water treatment, new wells, plus new pumps and pipes for aging systems. Nonprofit groups that work with rural communities are seeking state grants to upgrade rural water systems, she said.

Water engineer Dennis Keller of Visalia, who advises several rural water districts, said new wells, de-ionization of nitrates-laden water from existing wells, and switching to surface water supplies where practical could “over three to five decades” solve many rural water contamination problems.

Meanwhile, in Cutler, the Cutler Public Utilities District is seeking a grant to drill a new well by the end of the year, said Superintendent Dionicio Rodriguez Jr. The new well would allow a secondary well, which has DBCP “a little above the level” allowed, to stay idle until monthly test samples show improvement.