• About our Consent Decree

    It's All About Clean Water

    Clean water is essential for life. We need clean rivers and streams for our health, for recreation, and for the plants and animals that make it their home.

    To help clean up our waterways, MSD is implementing one of the largest public works programs in the history of our community.

    This multi-billion and multi-year initiative is designed to:

    • - Reduce combined sewer overflows or CSOs into local rivers and streams
    • - Eliminate sanitary sewer overflows or SSOs into local rivers and streams
    • - Assist customers who have experienced sewer backups from the public sewer.

    MSD is under a federal mandate, or Consent Decree, to reduce sewer overflows into local streams and rivers.

    Photo of pretty stream

    To date, MSD has reduced CSOs by 6 billion gallons a year, from 14 billion gallons to 8 billion gallons, and invested more than $1 billion in infrastructure improvements. This is about a third of the work necessary to achieve full compliance.

    MSD has been actively evaluating and implementing innovative, green, and cost-effective ways to reduce sewer overflows, including negotiating alternatives to existing projects required by the U.S. EPA.

    Although we are making good progress, our wet weather program is anticipated to take decades to complete due to project costs and the District's need to maintain the existing sewer system, which is more than 100 years old in some locations.

    The Consent Decrees and the Wet Weather Plan

    To address the issue of sewer overflows and achieve compliance with the Clean Water Act, the City of Cincinnati and Hamilton County entered into two federal Consent Decrees with the U.S. EPA, Ohio EPA, and the Ohio River Valley Water Sanitation Commission (ORSANCO) in 2002 and 2004.

    As required by the Consent Decrees, MSD developed a >$3.1 billion Wet Weather Improvement Plan, also known as the Wet Weather plan or WWIP, which was approved by the U.S. EPA in 2010. The Wet Weather plan includes a detailed list of projects to be implemented by MSD to reduce overflows. The work was originally conceived to be implemented in two phases (Phase 1 and Phase 2), but has since been expanded.

    For more details, please visit the links below:

    Several operational plans are required by either the Consent Decrees or the Wet Weather plan. MSD frequently reviews and updates these plans to ensure a timely response to sewer overflows. Please see the Downloads box for the most recent versions.

    Phases of the Wet Weather Plan

    The Wet Weather plan has been underway since 2009. It currently includes three phases, but additional phases will be needed:

    • Phase 1 (2009-2018): Phase 1 was rebranded as Project Groundwork and included 133 wet weather projects. All Phase 1 projects have achieved substantially completion for overflow control, and costs are trending below the original estimate of $1.14 billion.
    • Bridge (2018-2020): The Bridge includes 26 wet weather projects. Most of the bridge projects are in design and/or construction.
    • Phase 2 (after 2018): Phase 2 will be implemented in phases over multiple years, starting with Phase 2A. Phase 2A has not yet been approved.


    In the late 1980s and 1990s, the federal government, through the Clean Water Act, called for the elimination of sanitary sewer overflows (SSOs) and a reduction of discharges from combined sewer overflows (CSOs). This action affected every wastewater system in the country, including MSD. Increased scrutiny from the U.S. Department of Justice (DOJ) and U.S. EPA brought the issue to the forefront in the late 1990s as these government bodies began enforcing the ruling in large cities and leveling heavy civil penalties on those out of compliance.

    In 1999, MSD, which had already begun eliminating SSOs and reducing CSOs, entered into negotiations with the EPA, DOJ, and the State of Ohio to establish a formal remediation program that would be recognized and supported by the government, but also was affordable for local ratepayers. These negotiations resulted in the two Consent Decrees and the Wet Weather plan.

    Contact Us

    Report a Sewer Backup:
    (513) 352-4900 24/7 or online

    Customer Call Center:
    (513) 352-4900 24/7

    Project Customer Service:
    (513) 557-3594

    Development Services:
    (513) 244-1330

    Media Inquiries:
    (513) 557-7095


    MSD Mailing Address:
    1600 Gest St.
    Cincinnati, Ohio 45204

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