Developing A Costing Tool to Support Analysis and Selection of Projects to Address the Requirements of a Wet Weather, Watershed Based Consent Decree

The Sanitation District No. 1 of Northern Kentucky (SD1) is a sewer utility, which provides wastewater conveyance and treatment for Boone, Campbell and Kenton counties. SD1's service area comprises roughly 200 square miles, with approximately 12 square miles consisting of combined sewers, primarily in the older communities located along the Ohio River. In April 2007, SD1 entered into a Consent Decree (CD) with the USEPA and Commonwealth of Kentucky that requires SD1 to finalize, develop, submit, and implement watershed plans for the continued improvement of the separate sewer system (SSS), combined sewer system (CSS) and SD1's water reclamation facilities (WRF's). The CD requires that the watershed plans include elements of a combined sewer overflow (CSO) long term control plan and a sanitary sewer overflow (SSO) plan and allows SD1 to take a watershed approach to addressing all sources of pollution while eliminating SSOs and bringing their CSOs into compliance with the federal CSO Policy. The CD requires SD1 to submit five-year plans beginning in 2009 and allows for updates to those plans every five years until the controls are fully implemented in 2025. The first round of five-year Watershed Plans was submitted to the regulatory agencies in June 2009. While these plans focus on improvements over the next five years, CSO Policy dictates that a reasonable range of alternatives be considered in development of the final plan. In addition, the potential full program costs needed to be identified for SD1 to complete a financial capability assessment. Therefore, in order to develop comprehensive, system-wide watershed plans to address wet weather issues across SD1's service area, a database costing tool was developed that allowed for costing several hundred combinations of various system upgrades and wet weather control facilities at numerous levels of control so that SD1 could evaluate available alternatives for identifying potential full program costs and a feasible solution to address overflows across the system, to be partially implemented in the first five year plans