Stormwater Drainage

Each year, billions of gallons of stormwater runoff and snowmelt flow from roofs, driveways, parking lots and similar hard, impervious surfaces into the city’s combined sewer system. This drainage flows into the same underground pipe as unsanitary wastewater and must be treated at the wastewater treatment plant before it can be released back into the environment.

Federal and State regulations required DWSD to invest more than $1 billion in combined sewer overflow control (CSO) facilities to help prevent untreated overflows into the Detroit and Rouge rivers and preserve Detroit’s water quality. The drainage charge recovers the cost for operating Detroit’s CSO facilities and treating wet weather flows at the wastewater treatment plant -- more than $100 million annually.

Since 1975, most DWSD customers have been paying for drainage as part of their water and sewer bills. DWSD is updating its drainage charge program to ensure all city parcels are equitably billed for their share of drainage costs.

State regulation requires DWSD to rid millions of gallons more stormwater flow from the city’s combined sewers or invest an additional $1 billion in “gray” infrastructure. Together with city residents and businesses, DWSD is using green stormwater infrastructure (GSI) to meet permit requirements and make Detroit one of the “greenest” cities in America.

Customers who reduce stormwater runoff on their property – by disconnecting from the sewer system, planting rain gardens, installing detention areas and pervious pavement – can earn credits to be applied to your bill. A $5 million per year capital partnership program has been established to provide a 50/50 match for approved nonresidential GSI projects.