http://www.epa.gov/region5/water/lowermillcreek/

Hamilton County, Ohio — Revised Original Lower Mill Creek Sewer Overflow Partial Remedy

In January 2010 EPA approved a Wet Weather Improvement Plan (WWIP) to deal with combined sewer overflows (CSOs) and other wet weather discharge issues in Hamilton County, Ohio and the City of Cincinnati.  The WWIP addressed CSO discharges throughout the Metropolitan Sewer District (MSD) service area, including the Lower Mill Creek drainage areas.  The WWIP included a provision that provided that the Defendants could develop and submit for approval an alternative CSO control plan for the Lower Mill Creek portion of the service area.  The alternative plan could be approved if the revised plan provides equal or greater control of CSO annual volume as the original plan and can be completed by the established end date.

On December 18, 2012, the Defendants proposed a revised plan for addressing CSOs in the Lower Mill Creek service area (referred to as the “Revised Original LMCPR”). The proposed Revised Original LMCPR consisted of revised Attachments 1A, 1B, 1C and 2 to the WWIP, and a detailed technical document providing engineering and cost information on the proposed alternative plan. EPA posted the proposed alternative plan on this website, along with supporting information, and requested public comments on the alternative plan.

The Regulators have reviewed Defendants’ proposal, the comments received, and supplemental information provided by the Defendants on questions and issues raised by commenters.  In a letter dated May 30, 2013 EPA, on behalf of the team of regulators (U.S. EPA, State of Ohio, and ORSANCO) approved the Revised Original LMCPR.

Legal history

The revised Lower Mill Creek water plan was originally prompted by two court orders to reduce sewer overflows in the area served by the Metropolitan Sewer District of Greater Cincinnati. In 2010, the U.S. District Court entered an amendment to those orders. The amendment requires Hamilton County and the city of Cincinnati to implement what was originally a $3.3 billion remedy that was referred to as the "Wet Weather Improvement Program" or WWIP. The WWIP will address billions of gallons of untreated overflows discharging to local water bodies and the Ohio River each year.

In the legal amendment, EPA agreed to a phased-in schedule because of the high cost of the cleanup measures and the financial burden in the form of higher water rates it will put on area businesses and residents. The amendments also allowed the county and city to propose a money-saving alternative approach to deal with overflows in the Lower Mill Creek portion of the sewer district's service area.

Revised plan

The Revised Original LMCPR proposes to employ a strategic separation approach implemented on a watershed-by-watershed basis. In selected watersheds, stormwater would be removed from the wastewater collection system through a combination of strategic sewer separattion, green infrastructure and other methods. Around one stream called Lick Run, a new green corridor was proposed in the Revised Original LMCPR that would allow for overland flow of stormwater. The Lick Run green corridor could potentially provide valuable community benefits to distressed community areas, in addition to serving as a significant component of the wet weather control program.

One requirement of the original wet weather improvement program was for the Defendants  to construct a deep tunnel structure to store and channel excess stormwater. With this approval of the Revised Original LMCPR , the deep tunnel will not need to be built as part of the interim remedy.