Leon River
The Leon River watershed below Proctor Lake and above Belton Lake encompasses approximately 1,362 square miles in Bell, Hamilton, Coryell, Comanche, Erath and Mills counties. In 1996, the entire Leon River was placed on the Texas 303(d) List for bacteria levels that "sometimes exceed water quality standards". In 1996, the entire Leon River below Lake Proctor (Segment 1221) was placed on the 303(d) List for bacteria levels "Not Supporting Contact Recreation Use". The 2008 303(d) List identified all but two of the segment's assessment units as impaired or having a concern for near non-attainment resulting from elevated E. coli levels. Additionally, five tributaries of the Leon River are impaired for bacteria (1221A - Resley Creek, 1221B - South Leon River, 1221C - Pecan Creek, 1221D - Indian Creek, 1221F - Walnut Creek).
The Leon River watershed is a predominantly rural, agricultural watershed that primarily houses rangeland and row crop agricultural practices. Forests also cover a sizable amount of the watershed. A significant amount of dairy production also exists in the northern portion of the watershed.
A draft TMDL developed by TCEQ, but not adopted, identified sources of bacterial pollution in the Leon River watershed as wastewater treatment facility discharges, stormwater runoff, failing septic systems, wildlife and feral animals, as well as fecal deposition from livestock and pets. Water quality data support the assumption that these sources of bacterial contamination are present and contributing to the bacterial loading of the river. Ultimately, through the TMDL development process that utilized water quality monitoring, computer based modeling, watershed assessments and limited, library-dependent BST; TCEQ hypothesized that a 21% load reduction in bacteria levels would be needed to restore water quality in the Leon River.
In the midst of the TMDL development process, stakeholders sought to initiate the development of a WPP for the Leon River. Through TSSWCB project 06-12, Leon River Watershed Protection Plan Project, a WPP for the Leon River is being developed. The Brazos River Authority serves as the TSSWCB-contracted watershed coordinator for this process. The development of the Leon River WPP will proceed independent of this BST project; however, conclusions from this BST project will be integrated into the WPP through adaptive management.
In an effort to more accurately identify what potential sources truly are contributing to the bacterial loading of the Leon River, library-dependent BST will be re-employed. Advances in BST technologies and techniques since the original BST assessment was conducted for the TMDL and inclusion of additional sampling stations will produce higher certainty results which will be used to determine the most appropriate management measures needed.