Napa County Water Department

Find Napa County California water departments, districts, authorities, boards, and services. Water departments provide information on drinking water, treatment plants, sewage treatment, water conservation, and testing.


Calistoga Water Department 1232 Washington Street Calistoga CA 94515 707-942-2847


Napa County Water Department 804 1st Street Napa CA 94559 707-259-8600

Napa Water Billing 955 School Street Napa CA 94559 707-257-9508

Napa Water Department 1340 Clay Street Napa CA 94559 707-257-9521

St Helena Water Department 1480 Main Street St. Helena CA 94574 707-968-2745

Water Departments Near Me

Water Departments by City

About Water Departments

How is drinking water regulated?

The Safe Drinking Water Act sets standards for water quality and safety, and the U.S. Environmental Protection Agency has the authority to enforce the Act. Bottled water is regulated by the U.S. Food and Drug Administration.

Is water from private groundwater wells treated the same as public drinking water systems?

Regulations that protect public drinking water systems do not apply to privately owned wells. Owners of private wells are responsible for ensuring the quality and safety of their well water, including selecting a suitable site for wells and testing for contaminants.

What is a "boil water advisory"?

A boil water advisory is a notification from a government or public health agency to consumers that the drinking water supply may be contaminated with a pathogen. To disinfest water during a boil water advisory, water should be boiled at a rapid boil for at least one minute at sea level or three minutes at high altitudes.