Sedimentation

In addition to causing the loss of valuable topsoil, erosion also causes sedimentation in our waterways.

Erosion occurs when water runs over disturbed areas where the plant cover has been removed. We’ve probably all seen the little, and often large, gullies created by stormwater washing over these areas as it transports soil and rock to our streams. Excess sediment in our waterways is one of the leading causes of impairment to our creeks, rivers and lakes but is often unnoticed because the problems develop gradually. Sedimentation affects many things such as recreation, habitat, flooding and water treatment systems.

Deposition of sediment on the bottoms of our streams destroys the habitat for aquatic insect larvae that fish depend on for food. Many fish species cannot survive in streams with high concentrations of silt on the streambed and where sediment has decreased the oxygen content and sunlight. Excess sediment buildup in a stream can cause increased flooding and increased costs for water treatment.

In order to diminish sedimentation in our waterways, we all need to be informed about the effects of erosion and work together for the implementation of erosion controls at the local level. Learn how to protect your watershed at www.sgrwa.org