The GBRA Lab located at the General Offices of GBRA in Seguin, Texas provides technical assistance and support to GBRA's operations, as well as municipalities, water districts, industries, engineering firms and other organizations as they comply with federal, state and local regulatory requirements that protect water quality.

The GBRA Lab is equipped to perform physical, chemical and biological analyses of water from natural streams, water and wastewater treatment plants, groundwater wells and treatment residuals. The laboratory is also open to area classroom teachers and civic groups for tours. Students working on science projects often obtain technical expertise from the GBRA Lab employees and these employees frequently provide assistance to local and regional science fair competitions.

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A small team of dedicated employees staff the GBRA Lab to serve the public. These employees continually educate themselves through training offered by the U.S. Environmental Protection Agency, Texas Commission on Environmental Quality (TCEQ), Texas Engineering Extension Service, Texas Water Utility Association, The NELAC Institute (TNI) and other associations.

The National Environmental Laboratory Accreditation Congress (NELAC) was formed in 1995 to establish standards and promote the accreditation of environmental laboratories. The program, called the National Environmental Laboratory Accreditation Program (NELAP) includes standards covering laboratory practices, total quality management, personnel, training and facilities. However, on November 6, 2006 the NELAC/NELAP and the INELA (Institute for National Laboratory Environment Accreditation) merged to form TNI (The NELAC Institute). The purpose of this organization is to foster the generation of environmental data of known and documented quality through open, inclusive, and transparent process that is responsive to the needs of the community. For more information, visit

As of July 5, 2005 the TCEQ became a NELAC accrediting authority and began accepting applications from laboratories providing data to the commission. The GBRA Lab has adopted the NELAC/TNI standards and, as of May 20, 2008, the GBRA Lab was granted NELAC accreditation. Beginning July 1, 2008 the TCEQ will reject, without review or consideration, data generated after June 30, 2008 by a non-NELAC accredited laboratory, regardless of the circumstances under which those data are generated.

As of September 2006 the GBRA Lab became a mentor for the Hutton Fisheries Program. If you are a High School Student and are interested in working for us during the summer please click here!


933 East Court Street, Seguin, TX 78155
Office: 830-379-5822
Cell: 830-463-7160

Business Hours

Monday - Friday
8 a.m. - 5 p.m.

Holiday Closing Schedule

Monday, January 20, 2020
Friday, April 10, 2020
Monday, May 25, 2020
Thursday, July 2, 2020
Friday, July 3, 2020

© 1998 Guadalupe-Blanco River Authority