The Role of Remotely Sensed Data in Future Scenario Analyses at a Regional Scale - Fluvial Remote Sensing for Science and Management - page 280

Figure 12.5 Twelve major subbasins of the Willamette River and the 77 fifth-field hydrologic units contained within the catchment.
Reproduced from Willamette River Basin Planning Atlas: Trajectories of Environmental and Ecological Change, edited by David
Hulse, Stan Gregory, and Joan Baker for the Pacific Northwest Ecosystem Research Consortium (Oregon State University Press,
2002), with permission from Oregon State University Press; and from US Geological Service (1997).