What is and Illicit Discharge?

An Illicit Discharge is the result of an illegal and/or improper waste discharge into storm drain and ultimately a detention pond, a tributary and the DuPage River.  We like to use the saying “Only Rain Goes Down the Drain” This would include all stormwater runoff and snow melt.  This is important because all of our storm drains empty directly into a detention pond or stream, they DO NOT go to a treatment plan to be cleaned.

Illicit discharges may result from the connections of non-stormwater conveyance facilities (such as sanitary sewers) to the storm water system or may be the result of a waste spill flowing overland and into a storm sewer.

An example of an illicit connection would be the connection of a floor drain in a restaurant or automotive repair garage to a storm sewer. This would result in non-storm water wastes being flushed into the storm sewer system anytime the floors are washed in either facility. An example of an illicit discharge (without an illicit connection) would be the flushing of used motor oil down a storm sewer rather than properly recycling the waste oil.

Why is DuPage County Concerned about Illicit Discharges?

DuPage County residents have ranked the environment and water quality as import components of the quality of life in recent polls. To this end, many organizations in DuPage County have made strong commitments to preserve, protect and restore our natural resources.

In addition to the non-formal outreach activities to inform the general public about nonpoint source pollution, DuPage County is developing a formal Illicit Discharge Detection Program to identify and address illegal connections and discharges to the stormwater system. This program is a required component of the National Pollutant Discharge Elimination System Stormwater Permit which DuPage County and all of the communities in the watershed hold.  For the most up-to-date information on the Illicit Discharge Detection Program, follow this link to the DuPage County website.