While the Detroit Water and Sewerage Department (DWSD) has made significant progress in reducing the instances of untreated combined sewage being released into the Detroit and Rouge rivers, the federal government (under authority of the Clean Water Act of 1972) mandates that all illegal discharges stop by 2022. If it does not accomplish this with its current conbined sewer overflow system, DWSD will be required to spend $1 billion to expand its system of retention basins and pass the additional cost onto its customers. The city hopes to avoid that by reducing the amount of stormwater runoff at its main sources: impervious surfaces such as parking lots and rooftops.
At the same time, DWSD is changing the way it bills drainage user fees to nonresidential property owners based on the number of acres of impervious surfaces at each, so that all are being charged accurately, fairly and within legal requirements. In response to concerns expressed from the faith-based community about how the drainage charges were initially rolled out in 2016, the city has developed a new schedule for implementing the drainage fees that phases them in gradually over a period of years while also giving faith-based organizations, and all nonresidential properties, help in reducing their drainage bills for the long run.