Hydrology Layers from the National Hydrography Dataset


The National Hydrography Dataset (NHD) produced by the USGS and EPA is a comprehensive database of the nation's water resources. Three seperate map layers from NHD are available:

  • Flow lines (creeks, rivers and penstocks/flumes)
  • Water bodies
  • Watershed boundaries at the HUC-8 level

The map layers can be downloaded as apart of the AW Web Map Service (WMS) layer package.