OVERVIEW
Geography.
The South Elkhorn Creek
watershed covers western Fayette County, and northeastern Woodford County, and
the southern edges of Scott and Franklin Counties. The land is in the inner
subregion of the Bluegrass physiographic region, characterized by undulating
terrain and moderate rates of both surface runoff and groundwater drainage. The
watershed lies above thick layers of easily dissolved limestone that form
carbonate aquifers. Groundwater flows through channels in the limestone, so
caves and springs are common in regions with this geology.
Waterways. South Elkhorn Creek
empties into Elkhorn Creek at Forks of Elkhorn. Among the creeks that feed it
are Vaughns Branch, Wolf Run, Steeles Run, Town Branch, Cave Creek, Shannon Run,
Lee Branch, Beals Run, Buck Run, Hickman Branch, and Slickway Branch.
Land and water use. Land in the watershed is about 80% agricultural;
the rest is urban, and almost 10% is residential. The watershed includes
downtown Lexington and the University of Kentucky. Twenty-one businesses and
organizations hold permits for discharges into the creeks. See tables for
details.
Agency data assessment. The assessed creek segments in this watershed
include five that do not support some or all of their designated uses, based on
biological and/or water-quality data. Three others only partially support their
uses. Pathogens, organic enrichment, alterations of flow and habitat,
agricultural practices, municipal point sources, storm sewers, and urban runoff
contribute to the impairment of these streams. Total maximum daily load (TMDL)
plans are in progress for Wolf Run and Town Branch. See tables for details.
Watershed rankings. The ranking formula provides a preliminary
ranking by synthesizing a broad spectrum of watershed characteristics, current
conditions, and threats. This watershed ranks in the group with the highest need
for protection and/or restoration. This rating is for the watershed on average:
particular sites and particular waters within the watershed may vary widely. See
tables for details.
Volunteer data. Volunteers sample seventeen sites in the watershed.
Data for Beals Run, Steeles Branch, and one of the sites on South Elkhorn Creek
show high levels of bacteria indicative of fecal contamination (above 200
colonies/ml). Lees Branch exhibited elevated sulfate levels. Phosphorus levels
at every site where it was analyzed were well above the level that may cause
potential nutrient enrichment problems (> 0.1 mg/L). Town Branch and three
sites on South Elkhorn showed nitrate nitrogen concentrations above 10 mg/l (the
drinking water supply standard and EPA’s maximum contaminant level). Lead,
copper, selenium, and thallium were significant in several samples. Traces of
the organophosphate insecticide chlorpyrifos were detected at a few sites. See
tables for details.
Click here to view tables for this watershed, in PDF format. These
tables include land-use characteristics, designated uses, stream assessments,
public water supply and water withdrawal sites, permitted discharge sites,
gaging and sampling sites, volunteer data, and values for the 35 indicators used
in calculating watershed rankings. (You need Adobe Acrobat Reader to view the
tables: