Keeping Our Waters Clean
The hydrology of a watershed changes in response to site clearing, grading, tree removal, removal of forest litter, scrub brush, etc, either through agricultural or residential development. As an area urbanizes, vegetated, stabilized slopes whose vegetation slows water runoff are exchanged for roof tops, paved drives, gravel drives, parking lots, and the like. These areas are, by design, impervious to water infiltration and in turn, they convert virtually all rainfall into runoff. In addition, as natural wetlands and depressions are leveled for yards and parking, the watershed having lost much of its storage capacity, can no longer prevent rainfall from being converted to runoff.
Some notable pollution sources include: yard waste, pet and animal droppings, litter and debris, lawn fertilizers and pesticides to name the most common. Once introduced as runoff, these pollutants follow the watershed into streams, rivers, and eventually the great lake.
Illicit Discharge
The discharge of untreated sanitary wastewater (including industrial and commercial wastewater) or other polluting materials into a river, stream or other water body from: improper sewage connections - such as sources of sanitary sewage which should be connected to the sanitary sewer but are inappropriately connected to the storm sewer; effluent from improperly designed and/or operated septic systems; sanitary sewer overflows; improper disposal of waste products such as emptying a mobile home holding tank into a catch basin or pouring used motor oil into a catch basin; other discharges not composed entirely of storm water.
Illicit Connection
An improper physical connection of illicit discharges to the storm water drainage system, or other connections not authorized by the local authority (where required), to the storm water drainage system. Examples of illicit connections are: a) a floor drain in an automobile repair shop that is connected to the storm sewer rather than the sanitary sewer; and b) a septic tank discharge line that has been connected to the storm sewer. An improper connection of a source of storm water to the sanitary sewer would also be considered an illicit connection, for example, a parking lot catch basin that is tapped into the sanitary sewer. Illicit connections refer to a physical connection to the drainage system that either primarily conveys illicit discharges into the storm sewer system, or is not authorized or permitted by the local authority, if required.