The National Hydrography Dataset (NHD) includes a VisibilityFilter attribute that enables users to represent NHD vector features in the NHDPlus High Resolution (HR) at eight different map scales; ranging from 1:24,000 up to 1:5,000,000. Using a feature thinning model and workflow that approximates natural drainage density patterns for the conterminous United States, each feature is assigned a VisibilityFilter value, indicating an appropriate map scale, and all larger scales, for representing the features. This attribute is available for the NHDFlowline, NHDWaterbody, NHDArea, and NHDLine feature classes within NHDPlus HR. As the VisibilityFilter attribute is populated, data is available via download from https://www.usgs.gov/core-science-systems/ngp/national-hydrography.
As datasets with the VisibilityFilter attribute become available, ongoing research is being conducted to identify differences between datasets at the 1:100,000 map scale, as defined by the VisibilityFilter in the NHDPlus HR data, and the 1:100,000-scale NHD Medium Resolution data. The intent of this research is to identify patterns and areas of potential improvement within the methods used to calculate the VisibilityFilter attribute, and to subsequently improve the accuracy in later versions of the VisibilityFilter.
Science Support Framework Category: Data
Author(s): Hayley Thompson, Travis Landauer, Larry Stanislawski