Description: Snohomish County Public Works – Surface Water Management Division (SnoCo SWM) has upstream drainage area using 2013-2016 LiDAR-based digital elevation model (smoothed to 9ft resolution using Fourier transformation), current drainage inventory data, and Esri's ArcHydro toolbox. Initial basins were developed in 2019. Areas have not been individually QAQCed or verified. See this tracking log for individual drainage basin tracking:
Service Item Id: 79ff9e010a05435886d47986c0fda9b5
Copyright Text: Snohomish County Surface Water Management