What is an Illicit Discharge?

An illicit discharge is defined as any discharge to the Municipal Separate Storm Sewer System (MS4) that is not composed entirely of stormwater. These non-stormwater discharges occur due to illegal connections to the storm drain system from businesses or commercial establishments. As a result of these illicit connections, contaminated wastewater enters storm drains or directly into streams before receiving treatment from a wastewater treatment plant. Illicit connections may be intentional or may be unknown to the business owner and often are due to the connection of floor drains to the storm sewer system. Additional sources of illicit discharges can be failing septic systems, illegal dumping practices, and the improper disposal of sewage from recreational practices such as boating or camping.

Illicit discharge detection and elimination programs are designed to prevent contamination of ground and surface water supplies by monitoring, inspection, and removal of these illegal non-stormwater discharges. Call 412-364-0616, ext. 184 to report an illicit discharge.