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Ecological flow analyses of surface water withdrawal scenarios in the Cumberland and Tennessee River basins

October 24, 2019

This data release contains input data files (R scripts and supporting data files) and results tables associated with analyses that describe the predicted effects of surface-water withdrawal scenarios on specific stream flow characteristics (SFC), changes in fish species richness, and maximum allowable withdrawal (MAW) thresholds from stream sites within the Tennessee and Cumberland River basins. Surface-water withdrawal scenarios were constructed using two different models: 1) Percent-of-flow (POF) withdrawal model; 2) Constant-rate (CR) withdrawal model. The POF model simulated water withdrawal scenarios by reducing each daily streamflow value by a set percentage ranging from 0 to 40% withdrawal. The CR model simulated water withdrawals by reducing daily streamflow by a constant value (regardless of ambient/background daily streamflow values) ranging from 0.003 to 1.415 cubic meters per second (equal to 0.1 to 50.0 cubic feet per second). Additionally, four minimum flow levels were applied under each withdrawal model to investigate the potential effects of different levels of low-flow protection on fish species richness response to water withdrawals.

The primary INPUT files consist of three R scripts that contain executable code as well as detailed instructions, comments, and descriptions to fully reproduce the output results files. All files required to successfully reproduce output results are contained within the "INPUT" folder and "SupportingFiles" sub-folder that accompany this data release. Some of the supporting INPUT files consist of various datasets originally reported in previously published journal articles and were used to format and/or calculate various hydrologic or ecologic metrics (see citations below).

Basic site information (i.e., site number, site name, spatial coordinates, drainage area, ecoregion, etc) for each stream site is contained within siteInfo.txt file. Results tables for both POF and CR withdrawal models are contained within "SFC", "Richness", "Thresholds", and "SumThresholds" folders.

Knight, R.R., Cartwright, J.M., and Ladd, D.E., 2016, Streamflow and fish community diversity data for use in developing ecological limit functions for the Cumberland Plateau, northeastern Middle Tennessee and southwestern Kentucky, 2016: U.S. Geological Survey Data Release:

Knight, R.R., Gain, W.S., and Wolfe, W.J., 2012, Modelling ecological flow regime: an example from the Tennessee and Cumberland River basins: Ecohydrology, v. 5, no. 5, p. 613-627.

Knight, R.R., Murphy, J.C., Wolfe, W.J., Saylor, C.F., and Wales, A.K., 2014, Ecological limit functions relating fish community response to hydrologic departures of the ecological flow regime in the Tennessee River basin, United States: Ecohydrology, p. 1262-1280.

R Core Team (2018), R: A language and environment for statistical computing. R Foundation for Statistical Computing, Vienna, Austria. URL