In 1994, bathing beaches in Macomb county experienced frequent closings due to bacterial contamination. Metropolitan Beach in Harrison Township was closed a total of 61 days. Memorial Beach in St. Clair Shores was closed a total of 39 days. Since that time, both beaches have experienced intermittent closures each year during the recreational season.
Discharge of untreated or- under-treated sewage to surface water is one source of contamination. This occurs when sanitary sewer pipes designed to carry human waste from homes to wastewater treatment plants spill into rivers and streams. This may result from illegal connections to storm drains. This may also occur when older pipes that carry stormwater and sewage become overburdened during times of heavy precipitation. Overburdened retention basins and pump stations overflow, spilling large volumes of untreated sewage into rivers, which carry the waste downstream and into receiving waters such as lakes.