Wisconsin's Source Water
Assessment Program Summary

What is a Source Water Assessment?
A source water assessment is a document produced by WDNR staff and intended to provide basic information to public water suppliers regarding:
  • where their drinking water comes from
  • and the degree to which it may be impacted by potential sources of contamination.
Specifically, it includes the following:
  1. A brief description of Wisconsin’s Source Water Assessment Program
  2. A map of the system’s source water assessment area(s) and the potential contaminant sources within those area(s)
  3. A susceptibility determination based on presence of potential contaminant sources and other factors such as well construction, intake location, and geology
  4. Recommendations for source water protection
Progress Report: How Are We Doing? All States are required to complete source water assessments for both groundwater and surface water supplied systems as a result of the 1996 Amendments to the Safe Drinking Water Act.

Groundwater Systems
WDNR had delineated source water areas for all but a few groundwater systems. Potential contaminant inventories are being conducted by system and also on a statewide basis for certain potential contaminant source types. The inventories are nearly complete. Susceptibility determinations are being done using a newly developed computer application that uses information stored in various databases. When the susceptibility determinations are completed, source water protection recommendations and finalized assessments will soon follow. Our goal is to deliver assessments to municipal systems by December 2003 and to have assessments available to all other systems by December 2004. Brief summaries of all groundwater assessments will be available on the Internet.

Surface Water Systems
Wisconsin has completed assessments for all 19 of its surface water systems. These assessments are on the Internet. Source water protection is not mandatory for surface water systems. However, WDNR is working with the U.S. Environmental Protection Agency and other States to develop an approach to protection strategies for surface water systems.

A Source Water Assessment is Not a Wellhead Protection Plan
A “source water assessment” and a “wellhead protection plan” are two different documents with separate and distinct purposes. However, the source water assessment can aid a water system in its wellhead protection planning process by providing information necessary for completing a wellhead protection plan. Keep in mind that the source water assessment is produced by the WDNR, while the wellhead protection plan is developed by the water system and its wellhead protection planning team.

Source Water Protection: What Is It? Where Did It Come From?
Although it may seem like a new concept, source water protection is not new. In a lot of ways, it is just a name for the common sense efforts water systems have been making for years to ensure that the drinking water they provide is safe. In Wisconsin, source water protection for groundwater systems is synonymous with wellhead protection.
Source water protection efforts now include observing isolation distances, monitoring and/or remediating noncomplying potential sources of contamination, and implementing best management practices in a delineated wellhead protection area. Regardless of the specific efforts being made by a water system—source water protection is really just preventing contaminants from entering the water supply.
There are both state and federal rules that require source water protection to be done for wells. Congress amended the federal Safe Drinking Water Act in 1986 to require Wellhead Protection Programs in each state. In 1992, Wisconsin adopted its own wellhead protection rules to help further protect groundwater-supplied water systems.
Source water protection is not just a regulatory program—it is also a cooperative effort between the water suppliers, water users, WDNR, and other agencies to make sure that safe drinking water is being provided and water quality protected.

How Can I Learn More?
This article has presented a very general overview of Wisconsin’s Source Water Assessment and Protection efforts. If you have questions about source water assessments, contact Jeff Helmuth, WDNR Source Water Protection Coordinator, at (608) 266-5234.

Back to Wisconsin's Source Water Assessment Program

Last Revised: Monday October 13 2003