Consent Decree

Our Map for the Future

In 2007, the State of Missouri and the United States Environmental Protection Agency (EPA) filed a lawsuit against MSD regarding overflows. The Missouri Coalition for the Environment later joined the lawsuit as an intervener. Throughout MSD’s service area, there are hundreds of points where a combination of stormwater and wastewater discharges into local waterways from the sewer system during moderate to heavy rainstorms. These sewer overflow points act as relief valves when too much stormwater enters the sewer system. Without them, our community could experience thousands of basement backups and extensive street flooding.

Though most overflows predate MSD’s creation in 1954, they are still our responsibility, and our efforts to address the problem continue. From 1992 to 2012, MSD spent approximately $2.7 billion to remove more than 350 overflows. Fewer than 400 overflows remain. To address these, we are increasing  our collection and treatment capabilities—an expensive, complicated, and decades-long task.

In August 2011, the Department of Justice filed a settlement, or consent decree, requiring MSD to spend a minimum $4.7 billion over the next 23 years to address the issue of overflows and other sewer system improvements.

The consent decree agreement between MSD, the EPA, and the Missouri Coalition for the Environment was accepted by the United States District Court and has been entered and went into effect on April 27, 2012.

Learn more about the additional improvements MSD has in store thanks to the backing of the following amendments.

Consent Decree Amendments / Material Modifications

In October, 2013, an amendment to the original consent decree replaced two CSO Control Measures with a single storage facility.

First Material Amendment to Consent Decree (10/10/2013)

In June, 2018, an amendment to the original consent decree extended the program by five years and an additional $20 million.

Second Material Amendment to Consent Decree (06/22/2018)

In January, 2023, a third amendment to the original consent decree was approved. This Amendment combined two storage tunnel projects into a single project.

Third Material Amendment to Consent Decree (01/17/2023)

Consent Decree Non-Material Modifications / Approvals

Consent Decree Reports

Consent Decree Related Links