According to a LinkedIn post from the agency, the data sets evaluate “reservoir-specific evaporation for 188 major water supply reservoirs and gridded evaporation for six reference pond sizes.”
The data sets were created in collaboration with the Texas A&M Engineering Experiment Station (TEES), the Desert Research Institute, the U.S. Army Corps of Engineers — Fort Worth District and the Lower Colorado River Authority (LCRA).
“Reservoir evaporation is a critical component of water budgeting and operations but is often overlooked or simplified due to the difficulty in obtaining consistent, accurate estimates,” according to the agency’s Texas Reservoir Evaporation API website.
Historically, reservoir evaporation estimation throughout the state has relied on pan evaporation methods, measuring the rate at which water vaporizes from a pan or other open container.
However, this method tends to produce large biases and inconsistent results.
Instead, the new project created a daily reservoir evaporation database containing historical and near real-time, high-quality data records of evaporation rates and volumes for major reservoirs throughout the state.
As for limiting potential biases, the agency’s evaporation estimates incorporate meteorological forcing data and reservoir storage information to provide estimates of reservoir evaporation.
More information about the project can be found online.
