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<DIV STYLE="text-align:Left;font-size:12pt"><DIV><P><SPAN>This is a Washington State extract downloaded from the USGS in March 2019 and projected into WA State Plane Coordinates North. Waterbodies such as lake/pond features are represented in NHDWaterbody. They portray the spatial geometry and the attributes of the feature. These water polygons may have NHDFlowline artificial paths drawn through them to allow the representation of water flow direction. Other NHDWaterbody features are swamp/marsh, reservoir, playa, estuary, and ice mass. The National Hydrography Dataset (NHD) is a feature-based database that interconnects and uniquely identifies the stream segments or reaches that make up the nation's surface water drainage system. This high-resolution NHD, generally is developed at 1:24,000/1:12,000 scale, but many areas of Washington State have been improved to 1:4800 scale. NHD data was originally developed at 1:100,000-scale and exists at that scale for the whole country. Local resolution NHD is being developed where partners and data exist. The NHD contains reach codes for networked features, flow direction, names, and centerline representations for areal water bodies. Reaches are also defined on waterbodies and the approximate shorelines of the Great Lakes, the Atlantic and Pacific Oceans and the Gulf of Mexico. The NHD also incorporates the National Spatial Data Infrastructure framework criteria established by the Federal Geographic Data Committee. Stream Orders in Washington State range from 1 to 10. The smallest headwater streams are a 1, and the Columbia River is a 10.</SPAN></P></DIV></DIV> |