Polygon shapefile that includes the major watersheds of the Susquehanna River Basin (2006 boundary). This file was created by dissolving the wshed24K dataset into the major watersheds. The groupings were defined by the needs of the Susquehanna River Basin Commission (SRBC) and represent the SRBC's interpretation of major watersheds in the Susquehanna River Basin. This file was created to work in tandem with wshed24k.shp, subbasin.shp, and srb.shp. This dataset does not match the Hydrologic Unit Code (HUC) 11 digit watersheds.