The Mid and Lower Cibolo Creek Watersheds are located in Guadalupe, Bexar, Wilson, and Karnes counties. The headwaters of the watershed are located in the developing I-35 corridor North and East of San Antonio. Cibolo Creek meanders south approximately 90 stream miles before its confluence with the San Antonio River and includes Martinez Creek, Salatrillo Creek, and Clifton Branch (Location Map link).
In 2004 and still in 2014, the Texas Commission on Environmental Quality (TCEQ) listed the Lower Cibolo Creek as an impaired water body for primary contact recreation due to elevated levels of E. coli bacteria. Excessive amounts of the indicator bacteria E. coli in a water body signify an increased risk for disease-causing pathogens to be present in the water body. Both E. coli bacteria and other pathogenic organisms that may be present in Lower Cibolo Creek come from the fecal material of birds and warm-blooded mammals. The mid and Lower Cibolo Creek also have concerns for elevated levels of nitrate, total phosphorus, and depressed dissolved oxygen levels, which can hinder aquatic life.
Furthermore, the Mid and Lower Cibolo watersheds have seen increased residential development, as well as increased hydraulic fracturing activity associated with the Eagle Ford Shale formation. With this development, it is increasingly important to develop a plan that protects the watershed’s creeks and streams.
With this project, TWRI and San Antonio River Authority (SARA) will work together to facilitate local stakeholders in the development of a watershed protection plan. The plan, guided by stakeholder input and the best available data and science, will identify the best management practices to achieve the water quality improvement and watershed protection goals identified by stakeholders.
In concert with the WPP, SARA will expand stormwater water quality monitoring to provide additional data to support WPP development. Water quality modeling currently being developed for the Cibolo Creek Holistic Watershed Master Plan will contribute to a better understanding of pollutant loadings within the watershed. The new data, models, and information from local stakeholders will facilitate the development of an effective watershed protection plan addressing identified concerns in the watershed.
Project Partners – TWRI and SARA
Funding for this project was provided by the Texas State Soil and Water Conservation Board through the State Nonpoint Source Grant Program.