Insets: Water resources regions -- Alaska -- Hawaii (principal islands) -- Puerto Rico and Virgin Islands.
"Albers equal area projection based on parallels 29 1/2⁰ and 45 1/2⁰."
"Prepared in cooperation with Dept. of the Interior, National Park Service, Bureau of Reclamation, Bureau of Indian Affairs [and] Fish and Wildlife Service; Dept. of the Army, Corps of Engineers; Dept. of Agriculture, Soil Conservation Service [and] Forest Service; Tennessee Valley Authority; Dept. of Energy, Federal Energy Regulatory Commission; [and] Water Resources Council."
Includes dams and reservoirs, irrigation projects, watershed protection and flood prevention projects, hydroelectric powerplants, conveyance facilities, navigation and flood damage reduction projects, wild and scenic rivers, and hydrologic units.