Clear Creek: A TMDL Project for Volatile Organic Compounds
Counties: Brazoria, Fort Bend, Galveston, and Harris
Parameter: Volatile organic compounds
River Basin: San Jacinto–Brazos Coastal Basin
Segments: 1101, 1102
Background and Goals
The Clear Creek watershed drains parts of Fort Bend, Harris, Brazoria, and Galveston Counties. In 1993, the Texas Department of State Health Services (DSHS; then known as TDH) advised people against eating fish from portions of Clear Creek due to elevated concentrations in fish tissue of two volatile organic compounds (1,2-dichloroethane and 1,1,2-trichloroethane) and the pesticide chlordane (covered under another TMDL project). These volatile organic compounds are associated primarily with chemical manufacturing. An abandoned refinery was identified as the source of VOCs in Clear Creek. The goal of this TMDL project was to reduce concentrations of contaminants in fish tissue to levels that constitute an acceptable risk to consumers.
TMDLs and Implementation Plan
These TMDLs were first adopted by the commission on February 9, 2001. On June 14, 2002, they were revised to include minor clarifying language and adopted by the commission. The EPA approved the TMDLs on May 9, 2003, at which time they became part of the state’s Water Quality Management Plan.
- Four TMDLs for Volatile Organic Compounds in Clear Creek
- Response to Public Comment on the Clear Creek VOC TMDLs
The commission approved the implementation plan on October 12, 2001.
- Implementation Plan for Clear Creek VOC TMDLs
- Response to Public Comment on the Clear Creek VOC
Status and Implementation
The consumption ban was rescinded in October 2001; the fish consumption use is no longer identified as impaired for VOCs. Concentrations of VOCs in Clear Creek have declined by more than 90 percent since 1993. The Brio Refinery, a Superfund site, was identified as a major source of VOCs to the creek. The refinery site is located along Clear Creek near the tidal boundary. Contamination at the site is being addressed under the federal Superfund program.
In 2007, the TCEQ funded an assessment by DSHS of fish captured from the creek that verified that VOC levels in fish remain at acceptable levels. Information on fish tissue advisories and bans in Texas can be found on the DSHS website .
For More Information
For further information regarding this project, please e-mail us at email@example.com and mention the Clear Creek VOCs project in the subject line. Or call us at 512-239-6682.