• Restrictions on fish and wildlife consumption
• Degradation of fish and wildlife populations
• Degradation of benthos
• Restrictions on dredging activities
• Eutrophication or undesirable algae
• Beach closings
• Degradation of aesthetics
• Loss of fish and wildlife habitat

Although historical industrial and municipal discharges were the primary causes of environmental degradation in the Clinton River, and thus of its designation as an AOC, ongoing contamination problems are almost exclusively of nonpoint source origin. There are no major industrial discharges to the river or its tributaries of process water (only noncontact cooling water and stormwater), and most (though not all) municipalities have adequate industrial pretreatment programs and have implemented combined sewer control plans. As such, stormwater runoff as a category (including the two municipal systems still experiencing combined sewer overflows), is probably the single greatest source of water quality degradation.

Very rapid urban expansion and the subsequent loss of habitat is the second significant category of environmental problems related to water quality in the Clinton River watershed. Oakland County leads the state in new construction, and Macomb County is experiencing rapid urbanization as well. Wetlands and other wildlife habitat have been all but eliminated from the downstream portion of the basin, and natural drainage has been drastically altered throughout the watershed.

Historical point source discharges and ongoing nonpoint sources are responsible for sediment contamination in the mainstem of the Clinton River. Metals, polychlorinated biphenyls (PCBs), pesticides and other organics have been documented over several decades in a number of locations along the Clinton River from Pontiac to the mouths of both the river and the spillway.

For more information about these beneficial use impairments, visit the U.S. Environmental Protection Agency's Clinton River Area of Concern webpage at www.epa.gov/grtlakes/aoc/clintriv.html.