In recent history, use of groundwater to sustain rapid development in the basin has resulted in increasing base flows in the San Antonio River resulting from discharged groundwater-based return flows. This trend in increasing flows may continue if population growth in the basin is supported by additional groundwater usage or surface water transfers from outside the basin; however, lower river base flows may also result should water management strategies such as reuse, both direct and indirect, be increased. In any event, there is the potential to change the current physical, biological, and social resources in the lower San Antonio River sub-basin which provides the rationale behind the Texas Instream Flow Program (TIFP) lower San Antonio River sub-basin study.
