Drinking Water

The state of South Dakota began primary enforcement of the federal Safe Drinking Water Act (SDWA) in 1983. The South Dakota Drinking Water Program, part of DENR, develops and enforces the South Dakota Drinking Water Regulations that apply to public water systems in the state. Approximately 645 public water systems (PWS) currently exist in South Dakota.

Source Water Assessment and Protection

Source Water/

Wellhead Assessment

and Protection Planning Guide

Most drinking water systems in South Dakota depend on ground water for their source of drinking water. Other public drinking water systems depend on surface water supplies, such as lakes and streams, for drinking water. In both instances, it is likely that the drinking water system is using that source because it is the most reliable, economical, high-quality source of water available. Therefore, to protect the future of our state, it is important to protect our water supplies from potential contaminant sources.


The source water assessment and protection program was a follow up to the wellhead protection program which originated as part of the 1986 Amendments to the Federal Safe Drinking Water Act. Many of the source water ideas and actions originated in wellhead protection.  Although similar, the programs differ in a number of requirements, particularly in one major aspect, in that wellhead protection is authorized by state law and source water is not.  For more information on South Dakota's wellhead protection program click here.


The federal 1996 Safe Drinking Water Act Amendments directed that each state initiate a pollution prevention program that focuses on protecting the area surrounding a public drinking water supply. These Amendments required each state to identify existing and potential pollution sources that may impact the quality of public drinking water supplies. The South Dakota Department of Environment and Natural Resources coordinated this effort for our state. The department completed a source water assessment of each of the approximately 760 public water supply systems in South Dakota at the time. A complete assessment is a three-step process that included:


  1. Delineating the part of the watershed or ground water area that contributes water to the water supply;
  2. Identifying the significant potential sources of drinking water contamination in those areas;
  3. Determining the water supply's susceptibility to contamination from those sources.


Now what?

But what happens once your drinking water source is assessed? The Safe Drinking Water Act doesn't have much to say about that. That's where local communities come in. Once assessments are completed, state and local governments, water providers, and concerned individuals can create an action plan to address the problems and risks identified in the assessments. Even though the Safe Drinking Water Act is silent about how to protect and restore source waters, many tools exist to get the job done. A guidance document describing the general process that a community may use to develop a source water/wellhead protection plan is listed above. Please follow the links on this page for additional information on how you can help protect your drinking water source.

Clean Water Act Links
Source Water Protection Program Links