Estuaries have important commercial value. They serve as nursery grounds for two-thirds of the nation s commercial fish and shellfish. Estuaries are also home to ports and marinas that support shipping and other industrial activities. Some Impacts on Estuaries Pollution of coastal watersheds poses a threat to our nation s estuaries. Some typical impacts on estuarine systems include loss of habitat due to development, loss of recreational opportunities due to poor water quality, and loss of economic resources due to shellfish bed closures and a reduction in fisheries.
People can adversely affect estuaries.
Stresses caused by the overuse of estuarine resources have resulted in reduction in fisheries, loss of habitat and wildlife, and fish kills. Excessive nutrients from sources such as failing septic tanks, sewage treatment plants, storm water runoff, atmospheric deposition, industrial organic waste discharge, and contaminated runoff from fertilized farms or yards or from animal operations can adversely affect estuarine systems. Excessive nutrients in estuaries can result in accelerated eutrophication and algal blooms. As the algae die, they decay and rob the water of oxygen. The algae also prevent sunlight from penetrating the water.