Overview
An illicit discharge is any discharge to the storm sewer system that is not composed entirely of stormwater. These non-stormwater discharges may occur due to illegal connections to the storm drain system from business or commercial establishments. 

These illicit connections may result in contaminated waste water entering local water bodies via the storm sewer system. Untreated, these discharges contribute to the degradation of our valuable water resources. 

Illicit connections may be intentional or may be the result of connections made years ago when water quality issues were not a concern. Often these discharges are due to the connection of floor drains to the storm sewer system.

Other Sources
Other sources of illicit discharges can be failing septic systems (ISTS), illegal dumping practices, and the improper disposal of sewage from recreational practices such as boating or camping.

Illicit discharges may be detected when dry weather flow is observed. If the flow has a noticeable odor, appears discolored, or has an oily sheen, it may be the result of an illicit discharge. 

The elimination of illicit discharges is a goal of the city's Surface Water Pollution Prevention Plan (SWPPP). 

If you suspect there may be an illicit discharge occurring in the City of Roseville, please contact us at 651-792-7004.