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Source Water Protection (SWP)

Source Water Protection Practices

Source water protection practices are actions taken to prevent contamination of surface and groundwater sources of drinking water.  In choosing protection practices, water systems and government officials should account for the types of contaminant threats, physical landscape properties, public input, and other site-specific factors identified during the assessment process.

General Protection Practices

Photo depicts a wetland under a cloudy sky with mountains in the backgroundConserving wetlands in source water protection areas can help protect water quality, recharge aquifers, and maintain surface water flow during dry periods. Wetlands also provide important fish and wildlife habitat. Communities utilize a combination of regulatory and voluntary approaches to address threats to their drinking water supply. Given that source water protection is not required in most localities and that water utilities cannot regulate their source watersheds, approaches that complement a broad sweep of community objectives, whether protection of water quality, open space, or disaster resilience may receive more widespread public support and participation. Examples of source water protection practices include:

Source-Specific Protection Practices 

The links below provide information on common sources of contamination and the practices used to prevent and mitigate the impacts of pollution from those sources.

Clean Water Act Tools for Source Water Protection

The Clean Water Act establishes the basic structure for regulating quality standards for surface water and discharges of pollutants into the waters of the United States. Given that the Safe Drinking Water Act (SDWA), which sets standards for the quality of drinking water delivered to customers, does not establish authority for protecting drinking water sources, the Clean Water Act provides the primary regulatory tool for protecting source water quality. Federal, tribal, and state water program managers and the public all play a role in ensuring that Clean Water Act programs are adequately protective of drinking water supplies. A number of Clean Water Act "tools" can be used to protect drinking water resources. Examples include:

Clean Water Act-Safe Drinking Water Act Integration Resources: