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GAMA - Domestic Well Owners

Domestic well water is typically used by single family homeowners for private use and consumption. It is the responsibility of the well owner to ensure that their domestic well water is safe.

You may have concerns about the water from your domestic well. The information provided on this topic is divided into the following areas to help you find important information about domestic wells:

Guide for Domestic Well Owners

  • A PDF guide for domestic well owners, providing explanations for the basics of groundwater, private wells in California, and water quality testing, treatment, and protection.

Testing your well water

  • Information relevant to private well testing, such as who to contact for well testing, which chemicals you may want to test for, and how to interpret results.
  • Includes step-by-step checklist to help well owners evaluate the quality of their well water.

How to address well water quality problems?

  • Information on options for addressing water quality problems, such as available treatment or filtration methods.

Additional domestic well information

  • Additional links and resources made available from outside organizations and agencies that may be of use to domestic well users.

GAMA - OnLine Tools | California State Water Resources Control Board

  • Webpage containing tools created by the GAMA program and the USGS to help users understand groundwater quality in California.

Guía para los dueños de Pozos Domésticos

  • Una guía en PDF para propietarios de pozos domésticos, que brinda explicaciones sobre los conceptos básicos del agua subterránea, los pozos privados en California y las pruebas del agua, el tratamiento del agua y la protección de la calidad del agua.


If you are looking for records pertaining to a water well completion report (well log) you have two options:

1) Contact your local city or county environmental health department that issues well drilling permits and request a copy. A list of environmental health department permitting agencies can be found at the link below:
Department of Water Resources - Well Permitting Agencies

2) If your city or county health department does not have a copy, the Department of Water Resources (DWR) maintains an online database of well logs for approximately 800,000 wells statewide. DWR has redacted personal information from the well logs (name and address of well owner). The well logs are available at no charge from the Well Completion Report Map Application

If you are unable to find your well log using the online application, DWR staff can process your request manually, but you may be charged a fee for the service. Well log requests can be filed using the Well Completion Report Request Form to DWR.

For more information on public drinking water systems visit the Division of Drinking Water (DDW) Program website or contact a DDW Water District.

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State Water Resources Control Board
Division of Water Quality
Groundwater Ambient Monitoring & Assessment Program (GAMA)
1001 I Street, 15th Floor
Sacramento, CA 95814

Telephone: (916) 341-5577
Fax: (916) 341-5463