This data set contains hydrologic units (drainage basins) at a scale
of 1:2,000,000 for the conterminous United States and Alaska. The
attributes assigned to each unit follow the 8-digit Hydrologic ...
Most current set of Hydrologic Unit Codes and names for the
U.S., Alaska, Hawaii, South Pacific, and the Carribean. A
national dataset physically located at WCC, Portland, OR.
Collection Organization: ...