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Climate Change Adaptation Resource Center (ARC-X)

Climate Adaptation and Water Quality

Water Quality

EPA works with tribal, state, and local governments to improve and protect water quality.

EPA specifically works to restore and maintain oceans, watersheds, and their aquatic ecosystems to protect human health, support economic and recreational activities, and provide healthy habitat for fish, plants and wildlife.

Climate change can lead to greater variability in rainfall patterns, air temperature and corresponding  water temperature increases, and higher rates of sedimentation and erosion. These changes can threaten water quality by increasing stormwater runoff, more erosion and sedimentation, threaten source waters, and increase the frequency of harmful algal blooms. Changes in water quality of rivers, lakes or streams may also diminish the water quality of available source waters necessary for the provision of drinking water utilities.

Stormwater Runoff

Projected increases in the frequency and intensity of heavy precipitation events can create more stormwater runoff which can carry harmful nutrients, sediments, and pollutants into waterbodies.

Erosion and Sedimentation

Heavier downpours and more frequent and intense storms can carry sediment in stormwater runoff and increase river and stream velocity that leads to higher erosion rates.

Algal Blooms

Higher air temperatures will also have a corresponding affect on water temperature. Warmer waters, in combination with increased nutrients, can lead to more common outbreaks of harmful algal blooms.

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