AHED Subbasins

<div style='text-align:Left;'><div><div><p><span>Subbasins are grouped from Watershed boundaries and are consistent with NHD (National Hydrography Dataset) Subbasins. In areas where AHED Watersheds need major changes, the subsequent change in Subbaisn boundary will be communicated with USGS and NRCS (Natural Resources Conservation Service). Subbasins are USGS drainage areas one level smaller than Basins and each have a unique 8 Digit Hydrologic Unit Code or HUC. Topology rules are enforced among features of Basin, Subbasin, Watershed, SubWatershed and RainArea.</span></p></div></div></div>