St. Louis MSD CSO Volume Reduction Green Infrastructure Program

The Metropolitan St. Louis Sewer District (MSD) is a regional Special Sewer District that provides Wastewater and Stormwater services to the City of St. Louis and most of St. Louis County, Missouri. The service area includes a Combined Sewer System (CSS) in the City and the older portions of the County. In 2011, MSD completed a Combined Sewer Overflow Long-Term Control Plan (LTCP), which was formalized in a Consent Decree (CD) with the U.S. Environmental Protection Agency (EPA) in April, 2012. MSD’s Combined Sewer Overflow (CSO) control plan includes a $100 million CSO Volume Reduction Green Infrastructure Program in the areas of the City of St. Louis that flow toward the Mississippi River CSOs. MSD spent five years conducting a $3 million CSO Volume Reduction Green Infrastructure Pilot Program, culminating in a CD required final report completed in December 2015. The report explains what work was completed in the GI Pilot Program and the results, and outlines MSD’s plan for full implementation of the CSO Volume Reduction Green Infrastructure Program control measure. This presentation will briefly review the GI Pilot Program, with the main focus to discuss the findings of the GI Pilot Program and the plan for full-implementation of the $100 million CSO Volume Reduction Green Infrastructure Program. Included will be major components of the program, the expected reduction in CSO volume and use of an adaptive management approach to manage the CSO Volume Reduction Green Infrastructure Program through 2034.Implementation of green infrastructure for CSO volume reduction is one of many ways green infrastructure can be strategized for use in urban areas. As a separate entity from the City of St. Louis, MSD's plan highlights the important role that collaboration must have in the implementation of the CSO Volume Reduction Green Infrastructure Program. The plan for full implementation of the CSO Volume Reduction Green Infrastructure Program was developed with critical consideration of public-private partnerships, support of planned use areas and encouraging development and redevelopment in the City of St. Louis. Found to be effective in the GI Pilot Program, these same strategies are applicable to other communities planning and implementing green infrastructure programs.