Open Access Evapotranspiration Data Act This bill directs the U.S. Geological Survey (USGS) to establish an Open Access Evapotranspiration (OpenET) Data Program that supports the operational distribution of satellite-based evapotranspiration data generated under the program to sustain and enhance water resources. The bill defines evapotranspiration as the process by which water is transferred from the land to the atmosphere by (1) evaporation from soil and other surfaces, and (2) transpiration from plants. Under the program, the USGS must provide for the delivery of evapotranspiration data to advance the quantification of evaporation and consumptive water use and to provide data users with estimates of evapotranspiration data across large landscapes over certain periods of time.