What is Instream Flow? In the most basic sense, instream flow is water flowing in a stream channel. However, the term instream flow also implies flowing water that supports a larger stream ecosystem, including riparian and floodplain areas. For the purposes of the Texas TPWD program, instream flow is defined as the flow regime (quantity and timing of flow) that is adequate to maintain an ecologically sound environment.
Concern has arisen that water development without adequate provisions to protect instream flows will lead to degraded aquatic ecosystems. The increased demand for water, coupled with massive growth throughout Texas has raised issues concerning the depletion of the aquifers and decreasing flows in our streams. Particularly during periods of drought, the effect this has on threatened or endangered species and local economies is serious. Inadequate flows lead to eutrophic conditions and increased salinity in Texas bays, affecting fish and wildlife populations and coastal economies.
TRPA advocates for environmental instream flow regimes that preserve aquifers and maintain healthy stream flows.