A Spatial Tool for Watershed Characterization and Assessment in Northern Kentucky

Sanitation District No. 1 (District or SD1) serves 33 communities in Boone, Campbell, and Kenton Counties of Northern Kentucky. The District entered into a Consent Decree with the Kentucky Environmental and Public Protection Cabinet and the U.S. Department of Justice (on behalf of the US Environmental Protection Agency) to address sewage overflows within its jurisdiction. This Consent Decree is the country's first to be based on adaptive watershed management (Consent Decree, 2007).Some of the necessary activities to achieve the goals of the Consent Decree include the characterization of in-stream water quality; ranking of water quality problems and pollutant sources within 16 watersheds and 128 subwatersheds; and prioritization of hundreds of corrective design/build projects. The District has implemented a spatial analysis system called the Watershed Assessment Tool (WAT) to support these activities across its 580 square-mile jurisdiction.The WAT acts as a gateway to source information and a mechanism for identification and prioritization of mitigation opportunities. It can be used to assess relative impacts of pollutants on water quality across subwatersheds and watersheds and to examine relative contributions of different sources. WAT results can be combined with priority rankings from the District's parallel infrastructure assessment to prioritize the planning of watershed and infrastructure controls.The District has developed WAT to serve as the foundation for characterizing pollutant loads across 128 subwatersheds and to inform priority ranking of sources. WAT also serves as the organizing foundation of information to support the development of more detailed watershed models as necessary to calculate compliance with water quality standards.