Lower Leon Creek: Fish Tissue Sampling Project
below the site of
Kelly Air Force Base
County: Bexar
Parameters: Polychlorinated biphenyls
Basin: San Antonio River
Segment: 1906
Project Background and Goals
Lower Leon Creek, Segment 1906, flows from a point 100 meters upstream of State Highway 16 northwest of San Antonio in Bexar County to its confluence with the Medina River. The watershed is primarily a highly urbanized residential area, and drains approximately 190 square miles. The watershed includes Lackland Air Force Base and the former site of Kelly Air Force Base.
In 2002, the Texas Department of State Health Services issued an advisory restricting the consumption all species of fish from the creek because concentrations of PCBs in the tissues of fish posed an unacceptable risk to consumers. The goal of this project is to reduce concentrations of PCBs so that it will be safe for people to consume fish from the creek.
Status
The TCEQ contracted with DSHS to collect and analyze additional fish at five stations along Lower Leon Creek. Their analysis resulted in a new fish consumption advisory (ADV-42), which expanded the geographic extent of the original advisory (ADV-26).
Local interest in the fish consumption impairment also spurred a survey and characterization of PCBs in sediments. This survey was a collaborative effort of USGS, SARA, and CoSA PCEH. Monitoring at the former Kelly Air Force Base has also yielded PCB data.
The final report from USGS characterizing PCB levels in sediments from Lower Leon Creek and other streams in the San Antonio River basin was published in 2011.
- Assessment of Selected Contaminants in Streambed- and Suspended-Sediment Samples Collected in Bexar County,
Texas, 2007–09, Scientific Investigations Report 2011–5097
The TCEQ will evaluate all existing data and consult with stakeholder before deciding whether to initiate a TMDL project.
Public Participation
TCEQ staff are working with the Steering Committee of the San Antonio River Authority 
to keep the public informed of the status of fish tissue sampling activities. The Steering Committee is established under the Texas Clean Rivers Program.
For More Information
For additional information regarding this assessment, please e-mail us at tmdl@tceq.texas.gov, and reference the Lower Leon Creek fish tissue sampling project in the subject line. Or call us at 512-239-6682.
