Turbidity is a measure of clarity or cloudiness of water in a stream or lake. Turbidity levels increase as suspended solids and plankton (microscopic plants and animals) in the water column accumulate. Suspended solids are the amount of dissolved tiny particles in the water. Factors affecting the levels of suspended solids are storms, water temperature, land use and riparian zone width.

Adverse effects of high turbidity:

  • Sunlight becomes blocked, which reduces the amount of energy available for photosynthesis.
  • Suspended particles absorb heat, which raises surface water temperatures to above normal.
  • Eggs and benthic critters become stressed or buried as suspended particles settle to the bottom of the waterbody.
  • As suspended solids fall to the stream or lake bottom (sedimentation), substrate size is altered and percent embeddedness of rocks increases.
  • Sediments tend to carry nutrients, pesticides and other pollutants into and through the waterbody.