The primary purpose of Danvers' Town wide Illicit Discharge Detection and Elimination Program is to identify building sewer connections discharging to storm drains. Such connections referred to as "illicit discharges" allow untreated sewage to discharge to storm drains, and from there to local waterways and wetlands.
The program includes field inspections and sampling of storm drain outfalls as a means of identifying sub-catchment areas suspected of having illicit discharges. In sub-catchment areas identified as contaminated, storm drain manholes are inspected and sewer connections from buildings are dye tested to identify illicit discharges.