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System-wide Monitoring Program

Turbidity

Turbidity is a measure of the ability for light to transmit down through the water column. As suspended solids increase in the water, the amount of light traveling through the water column is reduced. This can influence the populations of organisms that are directly dependent upon light (phytoplankton and aquatic plants) and those, in turn that are dependent upon them as a food source. Suspended solids include particles of algae, sediment, detritus or solid waste. High levels of solids in the water can be indicators of problems from shoreline erosion, drainage ditches or waste facilities. It is beneficial to look at turbidity and suspended solids in connection with other biotic and abiotic factors in order to get a better understanding of its causes and consequences. If total solids were tested for, they should be analyzed for the portion of suspended solids vs. dissolved solids. Since sunlight is the basic energy source for most life forms, the degree of turbidity of the water has an important effect.

Turbidity affects fish and other aquatic life by:
  1. limiting photosynthetic processes and increasing respiration, oxygen use and the amount of carbon dioxide produced;
  2. clogging of fish gills and feeding apparatus of bottom dwelling animals by suspended particles; and/or
  3. obscuring vision of fish as they hunt food and smothering bottom-dwelling animals.