Climate Change and Water Quality - Minnesota Department of Health

Water Changes

Minnesota is a land of water. Our state has more than 11,000 lakes, 69,000 miles of rivers and streams, and over 10.6 million acres of wetlands. Water is essential to our economy, culture, and health. Climate change is expected to impact the frequency, duration, and intensity of rainfall events. This leads to issues with too much or too little water for Minnesotans. Read through our Water Quality & Quantity Summary (PDF) for a closer look at the details.

Water in Minnesota

image of cityscape with particulate matter

Minnesota benefits from more freshwater than any other of the 48 contiguous U.S. states. The viability of Minnesota’s industries, farms, utilities, and municipalities hinges an adequate supply of clean water. Climate-related changes in extreme weather and precipitation patterns will likely threaten existing water systems in Minnesota and significantly disrupt the hydrologic cycle, which is essential for human life.

How will climate change impact water?

image of water with algae

Climate change may impact Minnesota’s water quality and quantity by increasing precipitation, decreasing precipitation, and increasing temperatures of lakes and streams.

Increases in Water

image of waves on the lake

Increased precipitation, especially in large storm events, can cause river flooding and flash flooding. Flooding results from changes in land use, undersized sewer and stormwater pipes, and extreme precipitation or rapid snowmelt. The Midwest has seen an increase in very heavy precipitation in the last 50 years and more winter precipitation is falling as rain rather than snow.

Examples of increases in water include the following: changes in snow-to-precipitation ratio, increases in amounts of heavy precipitation, flooding, dew point changes, and extreme heat and humidity.

Public Health Issues

  • Physical injuries and destruction to property
  • Mold allergies
  • Damage to crops and farmland, affecting food security and access
  • Increased runoff, such as sediment, contaminants, nitrate, etc.
  • Sewage overflows
  • Contamination of surface water
  • Waterborne disease outbreaks from contaminated drinking water or recreational contact

Decreases in Water

image of crops

Some areas of the state will experience decreased precipitation. This is a result of localized large storm events, which leave some areas of the state drenched and others without any precipitation. An extended period of below-average precipitation can cause a drought, and it can be worsened by high temperatures or short, intense rainfalls that do not allow rainwater to soak into the ground.

Examples of decreases in water include the following: decreased precipitation,
drought, and significant changes in regional lake water levels.

Public Health Issues

  • Reduced soil moisture, groundwater and stream flows, and reduced water levels in lakes and wetlands
  • Potential concentration on pollutants
  • Decreased water supply for drinking water and agriculture
  • Negative effects to food supply
  • Wildfire dangers

Increases in Water Temperature

image of fish in a bucket

Minnesota will likely experience higher winter and summer temperatures as a result of climate change. The warmer weather causes bodies of water to absorb more heat in the summer and release less heat in the winter, resulting in overall warmer waters.

Public Health Issues

  • Warmer waters harm certain fish populations
  • Warmer waters increase the likelihood of harmful algal blooms and bacteria
  • Warmer waters may increase the survivability and breeding of insects that carry pathogens that can make you sick
  • Native species may be stressed by the changing temperatures

Health, Climate Change and Water Training Module

The MDH Climate & Health Program presented a Health, Climate Change & Water Training Webinar on Wednesday, January 24, 2018. As part of a seven-part series focused on health and climate change issues in Minnesota, the webinar and training module cover the observed climate changes in Minnesota, the public health issues related to climate change and water, and public health strategies to mitigate and adapt to climate change to reduce the health impacts. The training module can be referenced as a general education tool or as a "train the trainer" module for local public health professionals.

Missed the session? View the webinar recording above or download a copy of the 2018 Health, Climate Change, Water Training Slides (PPT).

Additional Resources

Updated Monday, 26-Sep-2022 10:13:55 CDT