Detroit Wastewater Plant

The Detroit Wastewater Plant is the largest single sewage plant in the USA.

Click here for Detroit Wastewater Plant fact sheet.

The location of the plant on the southeast side Detroit where the sewage wastewater discharge is at the southern end of the Detroit River where it enters into Lake Erie. In the first seven months of 2011, the Detroit wastewater plant dumped nearly 30 billion gallons of raw and partially treated sewage into Lake Erie. In the 1970s The Detroit Wastewater Treatment Plant was the single largest contributor of phosphorus to Lake Erie. It may well still be the largest single contributor of phosphorous to Lake Erie.

This regional wastewater treatment plant was constructed in 1940 and treats the waste of over 3 million people in 76 communities. It handles over 700 million gallons of wastewater per day

Detroit Wastewater Plant:

  • Primary capacity: 6 million m³/d        
  • Secondary capacity: 3.2 million m³/d
  • Average flow: 2.6 million m³/d
  • Population served: 3 million
  • Area served: 946 square miles
  • Secondary treatment type: Activated sludge
  • Solids treatment: Incineration

USEPA studies show that since 1994, the amount of phosphorous coming out of the Detroit Wastewater Plant has been increasing.(Source USEPA Web site study references) From 2008 through 2010 the Detroit Wastewater plant dumped 67 Billion gallons of raw and partially treated sewage into Lake Erie. It looks like 2011 will be a major CSO year with over 30 billion gallons dumped into Lake Erie from January 1 through August 5.(Source Michigan Department of Environmental Quality Combined Sewer overflow reports).

The Detroit wastewater plant canceled a contract to reduce overflows due to the lack of funding.  Also, there are many articles in Michigan papers about corruption in operations if the Detroit wastewater plant.  There are reports of failed equipment and understaffing which results in treatment failures. There need to be continuous monitors at the Detroit wastewater outfalls.  There are ongoing legal proceedings on this matter. While there are documentations of phosphorous loads at DTWWP in the 1970s, the data is lacking for much of the period beyond. There appears to be no independent analysis of the phosphorous loads from DTWWP to Lake Erie and whether or not DTWWP is meeting the targeted .5 mg/l load.  In contrast, other watersheds like the Chesapeake have states like Virginia, addressing phosphorous loading from the  wastewater plant discharges, primarily into rivers, by reducing discharges to .1 to .3.  Georgia also requires .08 to .3 mg/l with the lower limits required in discharges to sensitive lakes.Phosphorous discharges into Western Lake Erie/Heidelberg/Dolan

Following table prepared by David Baker/Heidelberg  presentation on the Detroit River phosphorous contribution. This chart also shows the Detroit River is a significant source of phosphorous.