Contours 5ft 2021 Tolt River Watershed

Tolt River watershed area 5ft contours derived from Lidar captured in 2021. Contour lines display at 5ft, 25ft, 50ft, 100ft, 200ft and 400ft intervals dependent on scale. Lines have been smoothed and generalized for display and performance.Development Detail:This vector tile service includes topographic contour lines representing elevation at 5-foot intervals within the Tolt River watershed area.The contours were derived from a bare earth - digital elevation model (DEM) with a pixel resolution of 1.5 feet. The lidar data that created the DEM were collected by NV5 Geospatial over the spring and summer months of 2021 and provided to the city by King County in 2022.The DEM used to generate the contours was filtered using the Focal Statistics tool in ArcGIS, which served to limit some abrupt changes in cell values. A 3x3 rectangular neighborhood analysis was applied and a mean value was calculated per raster cell.After running the Focal Statistics tool, 5-foot contours were generated from the filtered DEM. To reduce file size and improve performance, the contours were generalized further using the Smooth Line tool in ArcGIS. A smoothing algorithm type of Polynomial Approximation with Exponential Kernel (PAEK) and a smoothing tolerance of 20 feet was selected in the Smooth Line tool parameter options.Finally, after executing both generalization tools (Focal Statistics and Smooth Line), all lines less than 25 feet in length were omitted from the final output.Please note: The 5-foot contours are intended to be used for general reference and cartographic purposes only and should not be used for analysis purposes.

Data and Resources

Additional Info

Field Value
Source https://cos-data.seattle.gov/resource/233n-ys5f
Author Allen Grissom
Last Updated July 22, 2025, 19:50 (UTC)
Created July 22, 2025, 19:50 (UTC)
Contact Email mailto:mapgis.mapgis@seattle.gov
Contact Name SeattleData
Geographic Coverage -121.8866,47.6490,-121.5552,47.7872
Homepage https://data-seattlecitygis.opendata.arcgis.com/maps/SeattleCityGIS::contours-5ft-2021-tolt-river-watershed
Issued 2023-02-09T23:45:27.000Z
Last Update 2024-10-22T22:21:03.000Z
License The City of Seattle makes no representation or warranty as to its accuracy, and in particular, its accuracy as to labeling, dimensions, contours, property boundaries, or placement or location of any map feature thereof. 
Public Access Level public
Publisher City of Seattle ArcGIS Online
Theme geospatial
Unique Identifier https://www.arcgis.com/home/item.html?id=b4ebf3f611b849dfae7da782559d1372
harvest_object_id cb8b5226-8357-450a-86b7-9dbc109bb525
harvest_source_id 5365fd4f-4dee-4a64-8b1c-c2025205baa9
harvest_source_title seattle