How do you hide a 20 mg basin? Build it underground. While this may seem like a simple solution, there are daunting complexities of building a 20 mg underground CSO storage basin in the middle of a historic public park. In addition, the project had an aggressive schedule because of the consent decree’s requirement for the basin to be substantially operational by the end of 2018. The final design featured a blend of art and science that is hidden from the public’s view while quietly accomplishing its goal of mitigating combined sewer overflows.
Project Owner, Louisville MSD, is one of Kentucky’s communities with combined sewers. To mitigate combined sewer overflows (CSOs), MSD determined a 20 million-gallon (MG) CSO storage basin and a 30 MGD pump station was needed. Louisville MSD began the design of the Southwestern Parkway CSO Basin using conventional design-bid-build. However, local politics altered the basin’s location, resulting in significant delays for the Federal Consent Decree project. MSD decided to use a new project delivery method, Progressive Design-Build (PDB) to accelerate the schedule. MSD will discuss site selection and how public reactions directed the design. Presenters will describe how MSD prepared and managed its procurement to accelerate into design and construction. The project team will introduce PDB and describe the key differences between PDB and other delivery methods. The team will also explain the technical challenges to the project and discuss the innovative construction and design solutions that were developed to minimize impacts to the park and produce a final design that all stakeholders could agree on. Finally, the team will discuss their conclusions of the PDB process.