Welcome to the State of California 

DWSAP-Source Water Protection

Last Update: December 12, 2007

This page contains (A) FAQ and (B) other information pertinent to establishing a source water protection (SWP) program. 

A. Frequently Asked Questions

1. Why do SWP?

Answer: There are many reasons for undertaking SWP, including:

  • Because the most cost-effective method to ensure the safety of the drinking water supply is to protect the source from contamination
  • Because it is part of a "multi-barrier" approach to providing safe drinking water; treatment alone cannot always be successful in removing contaminants
  • To improve public perception of the safety of drinking water
  • Because safe drinking water is essential to the public health and economic well-being of communities

2. What is a source water assessment?

Answer: An evaluation, using a specified set of procedures, to determine the human activities that  are possible sources of contamination to which a drinking water source is most vulnerable.  Assessments provide the baseline information to begin SWP and may be used to prioritize SWP activities.

For more information about source water assessments, refer to the California Drinking Water Source Assessment and Protection website.

3. What are SWP measures?

Answer: SWP measures are practices to prevent contamination of ground water and surface water that are used or potentially used as sources of drinking water.  These include non-regulatory measures, such as Best Management Practices (BMPs), and regulatory methods.

4. What are BMPs?

Answer:  BMPs are standard operating procedures that can reduce the threats that activities at homes, businesses, agriculture, and industry can pose to water supplies.  BMPs, besides protecting water supplies, can sometimes increase the aesthetic beauty and value of residential and commercial properties.

5. What are some examples of non-regulatory measures that are effective for SWP?

Answer: Without adopting any new ordinances or regulations, communities can be successful in protecting water supplies, Non-regulatory measures include:

  • Good housekeeping practices at water sources and at industries, businesses, and homes
  • Public education
  • Land management to minimize release or runoff of contaminants
  • Purchase of land, development rights, or easements
  • Man-made systems and devices to prevent release of contaminants
  • Emergency response planning

6. What are some examples of regulatory measures that are effective for SWP?

Answer: Regulatory measures are appropriate when non-regulatory methods don’t work, when the contamination threat is particularly significant, or when federal, state, or regional regulations aren’t strong enough for local issues.  Regulatory measures include:

  • Land use controls
  • Subdivision growth controls
  • Zoning
  • Land use prohibitions
  • Regulations and permits
  • Construction and operating standards
  • Permit requirements
  • Public health regulations

B. Other Information

The California DWSAP Program Document (PDF, 1.6MB)Opens in new window.contains information about implementing voluntary SWP Programs (Chapter 11), management approaches, complete with lists of helpful documents and organizations (Chapter 12), and contingency planning (Chapter 13).

US EPA's Office of Ground Water and Drinking Water's website for SWP provides access to all the basic program information and features a guide of Internet-based source water resources that were either produced by (or paid for by) EPA. The site has contact information and direct links for state SWAP/source protection programs, EPA's regional source water programs, other relevant federal agencies, drinking water protection organizations, and environmental and public health organizations.

Cal/EPA's Department of Pesticide Regulation has information on its protection programs for surface water and groundwater.  The State Water Resources Control Board has a number of programs pertinent to source water protection.

Training Materials

CDPH's precursor, CDHS (with US EPA) developed two Source Water Protection MS PowerPoint presentations that may be used for training. There is a brief one-hour presentation (PowerPoint, 1.1 MB)Opens in new window. that provides an introduction to source water protection, and a full-day presentation (PowerPoint, 10MB )Opens in new window.that provides more detailed instruction on procedures for source water protection.

Also, see SWP case studies PowerPoint, 1.9MB)Opens in new window..

Funding Opportunities

Case Studies

We developed a presentation of case studies (PowerPoint, 1.9MB)Opens in new window.that describes several case studies of communities and water systems that have undertaken source water assessment and protection activities. Also, see

Other Resources

California Rural Water Association (CRWA) CRWA provides SWP assistance and other services to communities with populations less than 10,000.

There are many other sources of information on SWP, wellhead protection, and watershed protection available on the Internet. One humorous and informative site is the “RoboCow” video from the Prairie Farm Rehabilitation Administration of Canada.

Last modified on: 1/23/2008 8:52 PM