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.

Consent Decree Modifications

1. Revision of CSO Control Measure Design Criteria – Appendix D (Lemay CSO Outfall 063)

a. Letter to EPA with Proposed Revision (3/26/13)

b. Agreed Non-Material Consent Decree Modification (7/5/13)

2. Amendment to Consent Decree – Appendix D, Appendix E (Bissell Point Outfalls 051 and 052, Maline Creek CSO Controls, Post-Construction Monitoring Program)

a. Amendment to Consent Decree (10/10/13)

3. Alternative Supplemental Environmental Project (SEP)

a. Letter to EPA with Proposed Alternative SEP (9/15/14)

b. Approval of Alternative SEP (11/26/14)

4. Revisions of CSO Control Measure Design Criteria – Appendix D, Appendix E (Lemay CSO Outfall 063 and River Des Peres Storage Tunnels)

a. Letter to EPA with Proposed Revisions (Non-Material Modification A and Non-Material Modification B) (2/4/15)

b. Second Agreed Non-Material Consent Decree Modification for Lemay CSO Outfall 063 and RDP Storage Tunnels (Non-Material Modification A) (4/7/15)

c. Letter from EPA clarifying Design Criteria for CSO Control Measures for RDP Storage Tunnels (Non-Material Modification B) (3/9/15)

5. Approval CMOM Plan Modification – Line Cleaning Performance Standards and Acoustic Testing

a. Approval Modification of Capacity, Management, Operations and Maintenance (CMOM) Program Plan (12/02/2016)

6. Approval CMOM Plan Modification – Pump Station and Force Main Inspection and Testing Modification

a. Approval CMOM Plan Modification – Pump Station and Force Main Inspection and Testing Modification (12/10/2020)

Consent Decree Amendment

In June, 2018, an amendment to the original consent decree extended the program by five years and an additional $20 million. Learn more about the additional improvements MSD has in store thanks to the backing of the amendment.

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

Consent Decree Reports

Consent Decree Related Links