Amid two years of drought, Sonoma County and water quality agencies have released tools for well owners to ensure their water is safe to drink.

Private wells may have higher concentrations of naturally occurring but harmful substances as groundwater tables are lower than normal in some areas of Sonoma County, according to Christine Sosko, the county’s director of Environmental Health.

“Well owners should test their well water to ensure it is safe to consume,” Sosko said in a statement. “Testing for naturally occurring contaminants is highly recommended to ensure your well water is safe. If tests detect unhealthy substances, seek the advice of a private water treatment expert on the best way to remedy the problem.”

The county’s environmental health team, alongside the North Coast Regional Water Quality Control Board, the Sonoma County Water Agency and Permit Sonoma, created an online resource center for well owners. The website includes information on drinking water safety, how to test a well site and water treatment devices for residential use.

Sonoma County is home to an estimated 45,000 water wells, and to keep them at a safe drinking standard, owners have to consider the well’s location, construction, maintenance and the lithology of its aquifer, along with the amount of rainfall the area receives.

“Falling groundwater levels caused by drought conditions may increase levels of naturally occurring minerals in shallow groundwater that supplies drinking water to private domestic wells,” said Christopher Watt, senior engineering geologist with the North Coast Regional Water Board.

Though atmospheric rivers brought heavy showers in October, the county reminds well owners to use water sparingly. Storing water in underground aquifers can ensure there is enough water supplies if the drought continues through 2022.

Online resources for well owners can be found on Sonoma County’s emergency readiness, response and recovery page.