Drinking water quality

Drinking water quality is an important public health issue

Drinking water quality is an important public health issue, so state and local officials closely monitor for contaminants and work together to protect water quality.

Drinking water can be contaminated by man-made chemicals or by natural sources, like heavy metals in rock and soil. Natural waters contain impurities. Most impurities are harmless. However, drinking water that has certain levels of micro-organisms, minerals, man-made chemicals, or naturally-occurring pollutants can be harmful to your health.

Minnesotans get water from public and private sources

Minnesota has about 960 community water systems (CWS) that serve approximately 80% of Minnesota residents. Water from these systems can come from groundwater (water found in underground aquifers, the pores between sand, clay, and rock) or from surface sources (rivers, lakes, and streams). Most systems use groundwater from underground sources tapped by wells.

Though most systems get water from groundwater, about one-fourth of the state 's residents drink water that comes from surface water systems.

About one-fifth of Minnesota residents drink water that comes from private wells. 

Systems must meet Safe Drinking Water Act  standards

Community water systems in Minnesota are required to provide drinking water that meets the federal Safe Drinking Water Act (SDWA) standards. The MDH Drinking Water Protection Program is responsible for assuring that Minnesota 's public water supply systems comply with the SDWA.

MDH published Drinking Water Annual Reports provide summaries of water sampling and monitoring results for Minnesota. Local water suppliers also publish their own annual water quality reports (Consumer Confidence Reports) and distribute them to their customers. These may be obtained by request from local water utilities or  through MDH 's Search for your Consumer Confidence Report (CCR).

Local municipalities in Minnesota are required to conduct assessments and develop source water protection plans to protect their public water-supply wells. For more information, see MDH Source Water Protection . To search for source water assessments of local public water supplies, see Source Water Assessments .

Minnesota has a vast amount of aging infrastructure. To continue to supply safe drinking water, communities will need to replace this infrastructure over the next few decades. For more information, visit the State Auditor ’s   Infrastructure Stress Transparency Tool Version 2.0 , a series of interactive maps that visualize data on Minnesota ’s water and wastewater infrastructure.

Climate change impacts should be considered in all drinking water planning and operations in Minnesota. The MDHClimate &Health Program is working to increase awareness of the public health impacts of climate changes to our water quality and quantity.

For more information about initiatives to protect drinking water in Minnesota, see the Clean Water Fund and Water Contaminants and Your Health .

People with private wells should get them tested

About twenty percent of Minnesotans rely on private, household wells as their source of drinking water in their homes. While community water systems are tested regularly for a variety of contaminants, only newly-constructed private wells are required to be tested for contaminants in Minnesota.

Private well owners should maintain and test their own household water supply. MDH provides well owners with information about how to ensure their water is safe to drink. For more information, see Water Quality/Well Testing and the MDH Well Owner 's Handbook  (PDF).

Related topics :

• Minnesota Drinking Water Annual Report 2019 (PDF)
• Lead in drinking water
• Water quality and quantity (webinar 43:05)