Stormwater & Sanitary Discharges

DTW Stormwater Detention System

The DTW stormwater system has the capacity to detain more stormwater than at any other North American airport - approximately 515 million gallons. This is the equivalent to the water contained in 750 Olympic-sized swimming pools.  When empty, the system can contain a 4.5 inch runoff event.

This system is operated to contain stormwater generated during large rain and snow melt events in ponds located on DTW property, followed by controlled releases after the events subside and there is room in receiving streams near the airport. This strategy reduces the frequency and severity of downstream flooding.  Detroit Metropolitan Airport has invested more than $175 million on stormwater and deicing management system improvements since 1990, including the construction of four remote deicing pads. 

DTW Stormwater System Map

Dilute Deicing Fluid Discharges to the Downriver and Great Lakes Wastewater Treatment Facilities

All aircraft deicing at DTW is conducted in areas that drain to one of two wastewater treatment facilities. All runoff in these areas that contains greater than 2% aircraft deicing fluid, is recycled, and any spent aircraft deicing fluid runoff that cannot be recycled, is sent to either the Downriver Wastewater Treatment Facility located in Wyandotte, Michigan or the Great Lakes Water Authority Treatment Facility located in Detroit. These discharges are a significant element in the WCAA’s DTW NPDES permit compliance program. Through our team's efforts, Detroit Metropolitan Airport has been awarded the "Zero Violations Club" by the Downriver Plant for 17 of the last 18 years.