Description: <DIV STYLE="text-align:Left;"><DIV><DIV><P><SPAN>Data were collected by NV5 to meet standards laid out in the US Geological Survey’s (USGS) Elevation-Derived Hydrography (EDH) Acquisition Specifications (Elevation-Derived Hydrography Acquisition Specifications: Collection Area Requirements) and the EDH Representation, Extraction, Attribution, and Delineation (READ) Rules ( Elevation-Derived Hydrography—Representation, Extraction, Attribution, and Delineation Rules). The Stillaguamish EDH data was derived using a combination of six different previously collected lidar projects provided through Washington State's Department of Natural Resources Lidar Portal (Darrington 2003, North Puget USGS 2006, Tulalip 2013, Glacier Peak 2015, North Puget 2017, and Skagit Delta 2019). When available, breaklines delineating stream/river and lake/pond for the hydroflattening of these datasets were also used. The datasets were acquired and merged in 2023. </SPAN></P><P><SPAN>A hydrologic unit is defined by USGS as a drainage area delineated to nest in a multilevel, hierarchical drainage system. Its boundaries are defined by hydrographic and topographic criteria that delineate an area of land upstream from a specific point on a river, stream, or similar surface-water feature (https://pubs.usgs.gov/tm/11/a3/pdf/tm11-a3_5ed.pdf).</SPAN></P></DIV></DIV></DIV>
Service Item Id: bda238f6ed224c96afcabcae65f62f9b
Copyright Text: NV5 Global, Inc. (NV5 Geospatial)
United States Geological Survey
Washington State Department of Natural Resources
Washington State Department of Ecology