IMPERVIOUS SURFACES DEGRADE WATER QUALITY
Control stormwater runoff to protect the watershed
Nothing could be worse for the watershed than allowing stormwater to flow into the lakes, streams, and rivers. Stormwater runoff carries sediment and nutrients which can be detrimental to water quality.
During rain storms, stormwater flows across impervious surfaces. As it accumulates, it gathers loose particles from the ground, including excess nutrients, sediment, and toxic chemicals. When the stormwater runoff slows, these particles drop out of the waterflow and remain in place—possibly in our lakes and streams. It is important to slow stormwater runoff down before these pollutants can reach the surface water.
The illustration above depicts what happens as the proportion of impervious materials covering the surface area of the property increases. Consider how much of your property’s surface area is covered by greenery. If it’s not green, chances are it’s impervious. Research studies show that watersheds with as little as 10% impervious cover will begin to show the first stages of lake and stream degradation. Once this percentage reaches 20-30%, fish habitat, aquatic life, and water quality are dramatically impacted for the worse.