Potential Additional Water Supply Yield of Texas Reservoirs

Texas relies on over 180 major water supply reservoirs for nearly half of the supply needed for municipal, industrial, and agricultural and other uses. Increasing demands place great pressure on these reservoirs. This study attempts to identify reservoirs that still have the potential to provide additional firm supply, and how much additional firm supply might be available. This screening level study uses the Water Availability Model (WAM), a simulation model used for water planning and permitting in Texas, to test a reservoir's capacity to provide additional firm water supply above what is currently permitted. Environmental flow standards are considered for the river basins where they have been inserted into the WAM. The study identifies reservoirs in Texas that may still have the capacity to provide additional firm yield and estimates of the magnitude of the additional firm yields. This may provide useful information for regional and state water planning in Texas.