Sanitation District No. 1 of Northern Kentucky has signed the nation’s first wet weather consent decree based on the principles of adaptive watershed management. LimnoTech is working with the District, its gray and green infrastructure consultants, and stakeholders to develop watershed plans that meet requirements of the consent decree for sewer overflows.
The District must develop Four Basin Plans for 16 watersheds in a three-county area, with five-year updates. The plans must conform to the national Combined Sewer Overflow (CSO) Control Policy and identify remedial measures for sanitary sewer overflows (SSOs). Timetables must be identified to bring the CSOs into full compliance with water quality standards and eliminate SSOs in 20 years.
LimnoTech is providing watershed characterization and planning services, and coordinating these services with the District’s infrastructure consultants. The focus is to develop a comprehensive characterization of the District’s service area to ultimately support implementation of cost-effective water quality improvement projects. These efforts include comprehensive planning, data gathering and storage, Geographical Information System (GIS), watershed assessment, modeling, and providing assistance with communicating the watershed management approach to the regulatory agencies and the public.
LimnoTech developed 16 watershed characterization reports that document watershed features, waterbody conditions, and pollutant sources over the entire three-county area. LimnoTech also developed a Watershed Assessment Tool (WAT!) that aggregates information throughout the District’s service area and rates point and nonpoint sources in terms of their potential to generate pollutant loads. For more complex watersheds, LimnoTech developed detailed water quality models to simulate the effectiveness of different controls. Together, the reports and models will help the District prioritize improvement efforts.