Ewing Creek – Brick Church Equalization Facility
Nashville’s wastewater collection system began in the 1820’s as an assortment of clay and brick sewers, all discharging into the Cumberland River. Over time, the steady growth of people and places drove demand for over 2,900 miles of sewers, many combining sewage and stormwater. Passage of the Clean Water Act in 1975 set new water quality requirements for hundreds of cities nationwide. Metro Water Services’ ongoing Overflow Abatement Program has been reducing contaminated sewer overflows for decades. In 2009, a consent decree between the EPA and Metro set a deadline to eliminate sanitary sewer overflows and drastically reduce combined sewer overflows. The Ewing Creek – Brick Church Equalization Tank (~10MG) and Pump Station (~18 MGD) is one of over 80 projects that will help Metro achieve its overflow abatement goals.
Wilmot was chosen to lead a diverse projects team’s efforts to comply with Metro Water Services’ sustainability requirements. Due to the project’s location in a residential neighborhood and its visibility from two major highways, aesthetics and visibility of the tank were major concerns. This was addressed by burying a significant portion of the tank to reduce the height above grade and through landscaping design that utilizes a vegetated buffer to shield the site from view. Burying the tank meant that a large volume of rock would need to be excavated, resulting in over 2,000 truckloads of excavated material needing to be hauled to a landfill. The project team reduced this number dramatically by reusing as much of the material onsite as possible, resulting in cost savings and a reduction in pollution associated with truck traffic. Numerous other innovative, low impact development strategies were applied to the project including green infrastructure to reduce stormwater runoff, use of native/non-invasive plants, and the ability to locate a public park on the site in the future.