The Arkansas GIS Office is pleased to announce we have published for the first time five-foot contours dataset(s) for the entire State of Arkansas. The original input source data primarily consisted of the 10kmx10km National Elevation Dataset (NED) tiles produced by the USGS as a function of the 3D Elevation Program (3DEP). Where no NED tile existed, coverage was supplemented using DEM data that was previously collected and provided to the Arkansas GIS Office independent of the 3DEP collection effort.
The input tile was processed with GIS software to convert the DEM’s vertical linear units from meters to feet. In addition to this conversion the data was processed with focal statistics utilizing a 9×9 neighborhood grid to smooth the data to create a less jagged appearance that is more cartographically pleasing.
Due to shapefile size constraints, we were unable to add this dataset to our clip, zip, and ship product line. To compensate we exported a Contours shapefile based on the extent of the input tile in the corresponding State Plane coordinate system.
The tile footprint and contour data can be explored via browser at https://gis.arkansas.gov/dis/viewer/dem/dem_viewer/index.html or accessed via REST services in browser or via GIS Software at http://gis.arkansas.gov/arcgis/rest/services/FEATURESERVICES/Elevation/FeatureServer/5 and/or http://gis.arkansas.gov/arcgis/rest/services/ImageServices/CONTOURS_5FT_2019/MapServer respectively.
Additionally, we have made the entire 79GB dataset available via a zipped file geodatabase at http://geostor-elevation.geostor.org.s3.amazonaws.com/Contours/State/3DEP/UTM/CONTOURS_5FT_UTM.gdb.zip
Additional information is available via the product listing at http://gis.arkansas.gov/product/contours-5ft-stateplane-2019/ or http://gis.arkansas.gov/product/contours-5ft-utm-2019/
This data does not meet FEMA’s minimum interval requirements for Floodplain Management.