Communities worldwide rely on reservoirs for drinking water, hydroelectric power, irrigation, and more. These critical freshwater resources are affected by seasonal and long-term changes; water levels in reservoirs can dip during hot summer months or due to prolonged drought, or can flood after a particularly strong storm. Despite their importance, there are key gaps in our knowledge of reservoir structure and dynamics. Two recent papers use Landsat data to help fill in those gaps.
Researchers from the University of Southampton used Landsat data to identify where water advanced or retreated from 1984 to 2022, creating the first global dataset pinpointing the exact year of permanent surface water changes—such as when a reservoir formed or a stream dried up. The study can track changes in streams as narrow as 30m and lakes as small as 900m2. In a separate study, Texas A&M University researchers used Landsat data to build a global bathymetry dataset called ‘3D-LAKES’ that enables water managers to estimate reservoir storage capacity.
The above animation shows the Amistad Reservoir on the border of Texas and Mexico. It uses a natural-color Landsat image from 1985 overlaid onto a Copernicus Digital Elevation Model (DEM) and bathymetric data from the 3D-LAKES dataset. Vertical relief is exaggerated by a factor of four to emphasize topographic features and landforms. The reservoir is jointly managed by the U.S. and Mexico th …