Pulling It All Together: Louisville MSD's Successful Planning Process

In response to a Consent Decree entered into Federal Court in August of 2005, the Louisville and Jefferson County Metropolitan Sewer District (MSD) developed an Integrated Overflow Abatement Plan (IOAP) to control the community's combined sewer overflows (CSOs) and sanitary sewer overflows (SSOs). At the time MSD was formulating its IOAP approach, WEF was finalizing a guidance document titled “Guide to Managing Peak Wet Weather Flows in Municipal Wastewater Systems” (WEF 2006).This guide presented an approach to decision-making based on risk management principles. The impacts of sewer overflows were identified in the context of risks to community values (such as preserving public health, protecting property, achieving regulatory compliance, etc.). Specific performance measures allowed the quantification of risk reduction measures, allowing the development of a benefit/cost evaluation that considers and compares on an equal basis a broad range of community interests.MSD implemented this approach in five phases across four parallel paths, working concurrently with the technical team, the Stakeholder Group, the federal and state regulators and the general public. Phase 1 communicated information. Phase 2 defined the community values and metrics. Phase 3 included alternatives development and evaluation. Phase 4 performed the level of control analysis and developed implementation priorities. Phase 5 implemented the program.MSD successfully utilized this approach to produce an approvable plan, which met the community objectives at a reasonable cost. Regulatory approval for the IOAP was received within 9 months of submission. The price tag for the Final IOAP was estimated at $850 million, and will be implemented over a 19 year period that ends December 2024. This cost compares to an estimated $1.9 billion had MSD simply accepted a zero overflow level of protection for CSOs, and a 10 percent probability storm for elimination of SSOs.This paper will discuss MSD's approach, including the five project phases implemented across the four parallel paths.