Presenter: Dr. Sheeba M. Thomas Dominguez (San Antonio River Authority Senior Technical Engineer).
The San Antonio River Authority (River Authority) has been working on the development of comprehensive water quality models, tools, and analysis for more than a decade for quantitative water quality master planning and Best Management Practice (BMP)/Low Impact Development (LID) prioritization of the San Antonio River Basin.
The River Authority recently updated their water quality models for some of our urban watersheds, based on more current information such as land use, topography, stream network, subbasin delineation, meteorological data, stream flows, ambient and storm water quality sampling data, wastewater flows, sanitary sewer overflows (SSO), recharge and channel losses, spring flows, and diversions.
Available floodplain hydraulic models were reviewed and used to generate rating tables for model reaches. The revised models were calibrated, and peer reviewed to observed flow and constituent data following River Authority’s water quality modeling standards. The suite of water quality modeling tools such as the SARA Load Reduction Tool (LRT) which automatically determine load reduction needed for each subbasin and constituent to meet stream standards and the Enhanced BMP Tool to determine the optimal (minimal cost) combinations of BMP/LID were also developed. The results from the models and tool runs have been further analyzed to determine where water quality improvement measures need to be implemented for improving the surface water quality conditions.
The results from these efforts serve as a valuable best science-based resource to the communities in fostering efforts for water quality preservation/mitigation.