CREATING A RATING SYSTEM AND USING KARST STUDIES TO INVESTIGATE SOURCE WATER PROTECTION AREAS FOR COMMUNITY DRINKING WATER SPRINGS IN TENNESSEE

Sixty-six community public water systems within the state of Tennessee use springs as a primary or secondary water source. These karst groundwater resources are critical for these communities, serving over 711,000 people statewide. Public water systems are required to identify the area that contributes water to the water supply, also known as the source water protection area (SWPA). A recent partnership between the U.S. Geological Survey (USGS) and Tennessee Department of Conservation (TDEC) seeks to examine previously identified SWPA for community drinking water springs and then conduct groundwater tracing to confirm recharge area boundaries for higher priority karst springs. In fall 2021, SWPA were reviewed by USGS and TDEC staff using a rubric scoring system. The review helped to identify possible vulnerabilities or complexities that may exist based upon maturity of karst development, underlying geology, or logic used to delineate the initial SWPA. Using this scoring system, the springs were then ranked and priorities for fieldwork were established. In late winter 2021, fieldwork began on three spring systems in middle and south Tennessee. These systems (Cowan, Jasper, and Woodbury) are located along the Cumberland Plateau and Eastern Highland Rim in areas where the hydrology has been significantly altered by karst processes. Groundwater traces both within and adjacent to established SWPA have shown the systems to be more complex than previously depicted and the results will help community public water systems draft new and more accurate SWPAs for the springs. SWPAs are then used to assess the susceptibility of the drinking water source to potential contamination. The partnership is a five-year study which uses research results to provide public water systems with information to better manage their drinking water resources.