Carters Creek Total Maximum Daily Load Implementation Project Watershed Source Survey and GIS Mapping: Task 3
L. Gregory, J. Murray and C. Schulz
The Carters Creek watershed is a tributary of the Navasota River and covers approximately 56.9 square miles in Brazos County. Of this area, 57% is urbanized (Figure 1) through development associated with the cities of Bryan and College Station. Within the Carters Creek watershed, Carters Creek, Burton Creek and Country Club Branch are all considered impaired due to elevated levels of Escherichia coli (E. coli). These waterbodies were listed on the Texas Commission on Environmental Quality’s (TCEQ) 303(d) list for bacterial impairments in 1999 for Carters Creek and 2006 for Burton Creek and Country Club Branch (TCEQ 2012). Each of these waterbodies was listed impaired for not meeting the E. coli standard for Primary Contact Recreation which is a geometric mean of 126 colony forming units (CFU)/100 mL of water. Initial listing of these waterbodies was supported by monitoring conducted by TCEQ and the Brazos River Authority (BRA).
In 2007, the TCEQ Total Maximum Daily Load (TMDL) Team began the process of developing a TMDL and TMDL Implementation Plan for the Carters Creek watershed. Watershed stakeholders were engaged in the process to develop recommendations for management measures needed to restore water quality in the Carters Creek watershed. In 2014, a TMDL was completed for each creek and as a result, they are proposed for delisting in the 2014 Texas Integrated Report (TCEQ 2014).