Fig. 1: Comparison of number and reservoir storage capacity of medium vs. large dams.
From: The evolution of dam induced river fragmentation in the United States

a Map of the contiguous United States (CONUS) with major rivers and major river basin aridity. b Map of CONUS with large dams and medium dams. c The total number of dams present in each major river basin. d Total reservoir storage present in each major river basin. The percentage of  medium dams contributing to each total are placed on top of the bars in c and d.