Source Water Assessments
Of Public Water Systems

The Minnesota Department of Health (MDH) has recently completed "source water assessments" for all of the approximately 7,000 public water systems in the state. Each assessment provides a concise summary of available information regarding the source(s) - such as a well, lake, or river - supplying a public water system.

To find and view source water assessments, click on the button below.
Or, keep reading to find out more about source water assessments.

What is a Source Water Assessment?

A Source Water Assessment is a document produced by MDH staff and intended to provide basic information to public water suppliers and the general public regarding: 1) where their drinking water comes from, and 2) the degree to which it may be impacted by potential sources of contamination.

Specifically, a source water assessment includes the following:

• The status of a public water system's source water protection plan.
• A description of the water source(s) used by the public water system.
• A determination of the susceptibility of the water sources to contamination.
• A list of contaminants of concern for the water source(s) and potential contaminant sources that could impact the water supply.

Please note that these assessments focus on the source of water, rather than the finished water supplied to customers at their taps. A public water system may treat the water to protect and improve its quality before it reaches the consumer.

Why Source Water Assessments Were Created

The 1996 amendments to the federal Safe Drinking Water Act require MDH to produce source water assessments for all Minnesota's public water systems and make assessment results available to the public.

How Source Water Assessments Are Being Used

Some of the ways source water assessments are being used include:

• By the public - to understand where their drinking water comes from.
• By contamination cleanup programs - to set priorities and determine the level of cleanup needed.
• By permitting programs - to assess if a proposed land use has the potential to adversely affect a public water supply.
• By MDH - when bringing water suppliers into the wellhead protection program.

How Source Water Assessments Were Created And Will Be Updated

Source water assessments were created by MDH using existing data such as water sampling results, water system surveys, and well records. For systems using surface water, the assessment was created in consultation with representatives from the public water system.

Assessments are updated as soon as new information (such as well construction data) is added to the databases used to generate the assessments. The assessments shown on the web site are then updated to reflect these changes.

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 and provides an update of the system's progress in source water protection. Note that the source water assessment is produced by MDH, while the wellhead protection plan is developed by the water system and its wellhead protection planning team.

For More Information

For more information about source water assessments, contact the MDH Source Water Protection Planner for your region of the state. You can also visit the US Environmental Protection Agency Source Water Assessment web site.

For questions about this page, contact the Drinking Water Protection Program: health.drinkingwater@state.mn.us or 651-201-4700. For specific Drinking Water questions, please use the contacts listed on our Contact Us page.