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"Groundwater - Protect it Today, You May Drink It Tomorrow" Nevada Division of Environmental Protection Groundwater Branch. Winning drawing held in a contest at Nevada grade schools to develop a logo for the Nevada groundwater protection efforts.
"Groundwater - Protect it Today, You May Drink It Tomorrow" Nevada Division of Environmental Protection Groundwater Branch. Winning drawing held in a contest at Nevada grade schools to develop a logo for the Nevada groundwater protection efforts.

Source Water Protection (SWP)

The Ground Water Office supports Region 9 States, Tribes and the Pacific Islands in their efforts to develop and implement a Source Water Protection (SWP) Program. Source water is untreated water from streams, rivers, lakes, or underground aquifers which is used to supply private wells and public drinking water.

The 1996 Amendments to the Safe Drinking Water Act required states to develop and implement a Source Water Assessment Program (SWAP). Tribes and the Pacific Islands are not required to conduct SWAPs but are encouraged. The Ground Water Office has a Tribal SWP Program which offers technical assistance on SWP issues and funding to conduct assessments and develop/implement SWP programs.

For more information on Region 9's support of SWP in the Pacific Islands, contact:

Kate Rao (rao.kate@epa.gov)
(415) 972-3533

The first phase in a SWP program is to conduct a 4-step source water assessment of your drinking water supply. A key output of SWAP is an assessment of all public drinking water sources (surface and ground water). The assessments are a valuable planning tool which: identify and delineate protection areas surrounding sources of drinking water; inventory potential sources of contamination within those protection areas; evaluate the vulnerability of the sources of drinking water based on the proximity and frequency of sources of contamination; and provide key information necessary to develop and implement source water protection programs. Once an assessment is completed, a community can develop and implement a source water protection (SWP) program that mitigates the identified to the drinking water source(s).

Many communities began their SWP efforts under the Wellhead Protection Program (WHPP). The SWP has grown to go beyond the WHPP’s scope of protecting only ground water sources by focusing on protecting all sources of drinking water, both ground and surface water sources.

All Region 9 States: Arizona, California, Hawaii, and Nevada, Exiting EPA (disclaimer) have completed the required assessments.

With the completion of the assessments, states and/or local authorities can use this information to develop and implement new or additional strategies to protect current and future sources of drinking water.

Contact information

For general information about the EPA’s SWP program, visit EPA’s national Source Water Protection web site.

For information concerning a Region 9 state’s SWAP/SWP program, go to EPA SWP contact information. For general information regarding implementation of the SWP program in Region 9, contact:

Through a grant provided by EPA, the National Rural Water Association works with communities to develop and implement source water protection plans. If you are interested in learning more about your state Rural Water Association affiliate and what type of technical assistance support they offer, please contact:

Kate Rao (rao.kate@epa.gov)
(415) 972-3533

Region 9 Topics and Programs | A-Z Index


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