Description: These are lines which are representative of selected major stream centerlines. They are generated from stream mile mark points for use in local flood insurance studies; includes attributes for unique stream names (see feature Attribute Tables).They are a subset of the stream layer, which is based on the United States Geological Survey (U.S.G.S.) National Hydrography Dataset (NHD). LOJIC has matched it with the Hydrographic layer (HL) features which are more positionally accurate. The USGS NHD features are out of date. These out of date USGS features, when identified have been modified by the latest LOJIC mapping and aerial imagery.