Lafayette, Tennessee Karst Groundwater Dye Tracing, Water Year 2023

Karst hydrologic systems are important resources in the state of Tennessee both as drinking water resources and as centers for possible biological diversity. These systems are susceptible to contamination due to the inherent connectivity between surface water and groundwater systems in karst systems. A partnership between the U.S. Geological Survey (USGS) and Tennessee Department of Conservation (TDEC) was formed to investigate karst spring systems across the state utilizing fluorescent groundwater tracing, particularly in areas where these resources may be used as drinking water sources. In fall 2021, USGS and TDEC staff identified possible vulnerabilities or complexities that may exist within karst spring systems based upon maturity of karst development, underlying geology, and uncertainties related to estimated recharge areas. Based upon initial research, several study areas were selected.  Dye tracing efforts began in March 2022 in the communities of Woodbury, Cowan, Jasper, and Vanleer.  In Water Year 2023 (10/1/2022-9/30/2023) fieldwork concluded on these initial communities and new dye tracing efforts were started in Caryville, Morristown, and Lafayette.  Collectively these communities span multiple physiographic regions including the western and eastern Cumberland Plateau escarpments, the Western and Eastern Highland Rim, and the Valley and Ridge Province.  All these communities rely on karst groundwater as a drinking water source and in areas where the hydrology has been significantly altered by karst processes and thus the groundwater pathways are complex and unpredictable. 
The community of Lafayette is in Macon County, Tennessee along the northern portion of the Eastern Highland Rim.  Streams in the study area drain north to the Barren River in Kentucky.  The study area is primarily underlain by the Mississippian Fort Payne Formation, though Silurian and Ordovician strata is exposed  in some of the more-deeply dissected valleys.  Karstification in the study area occurs in bioherms of limestone in the Fort Payne Formation that are both vertically and laterally discontinuous.  Streams in areas underlain by limestone can sink into the subsurface and springs located further downstream discharge karst groundwater creating the perennial reaches of most streams.  Dye tracing work began in the Lafayette area in June 2023 with a round of three dye injections occurring on July 5, 2023. The monitoring network consisted of 34 monitoring sites where charcoal packets were deployed.
This data release contains shapefiles that relate to dye injection locations, monitoring sites, and dye traces conducted in the Lafayette area during the 2023 Water Year (10/1/2022-9/30/2023).  All files were created in ArcGIS Pro and each shapefile contains associated attributes for the features contained within. Layer files are included with the datasets to match symbology found in figures in the accompanying report. All shapefiles and layers were created and modified in ArcGIS software.  For a full description of the methods to create these files, see Process Steps in "LF23_Metadata.xml" metadata file.
Data within each child item of this data release are named with a two-letter abbreviation unique for the community where the tracing occurred and the water year the work was conducted (e.g. WD23). Abbreviations for the communities are as followed: CR = Caryville, CW = Cowan, JS = Jasper, LF = Lafayette, MR = Morristown, VN = Vanleer, WD = Woodbury.

Tags: caves, dye-tracing, eastern-highland-rim, freshwater-ecosystems, groundwater, groundwater-and-surface-water-interaction, groundwater-flow, hydrogeology, karst, karst-areas, karst-hydrology, lafayette, little-puncheon-creek, long-creek, macon-county, puncheon-creek, spring-creek, springs, tennessee, tennessee-department-of-environment-and-conservation, usgs-6536ce1fd34ee4b6e05bb7f5
Organization: Department of the Interior