Geographic Services, Washington State Department of TransportationSelected major lakes and reservoirs of Washington State are depicted as polygons. Major reservoirs on the Columbia and Snake Rivers, and Lake Washington are excluded.ArcGIS FeatureLayerhttps://hub.arcgis.com/datasets/67f99c89544d4dc29efffe6a953c178a_0engState of Washington Geospatial Open Data PortalPublicWSDOT - Major Lakes (1:500K) [Washington (State)]Web servicesWashington (State)Last Modified: 2025-10-07