Description: National Hydrography Dataset NHDFlowline layer with spatial representation of existing water uses defined in Title 25 Environmental Protection, Department of Environmental Protection, Chapter 93, Water Quality Standards. The Pennsylvania Code just cited provides a definition for distinguishing between designated and existing use classification. This GIS layer displays these uses spatially on an interactive stream map. Public users can drill down to locations on the map to view and map the existing uses of the water bodies of interest. The layer can also be used in conjunction with other spatially referenced data for spatial analyses.
Description: This is the Department's legacy master stream coverage. The last updates to this layer occurred in late 2004. This layer has been replaced by the High Resolution National Hydrography Dataset (NHD) and as such should only be used to aid in identifying legacy stream codes. This layer was digitized at a scale of 1/24,000. All streams are connected and have flow direction. Each stream is identified by a unique 5-digit stream code found in the WRDS (Water Resource Data System) field. The streams are further divided into segments. The first stream segment flows from the headwaters to the first tributary. Subsequent segments are tributary to tributary. The final segment flows from the last tributary to the mouth which for purposes of this data layer is defined as the point at which the stream crosses the Pennsylvania boundary. The unique segment identifier is constructed from three concatenated fields. The stream code, downstream river mile, and finally the upstream river mile of the segment boundaries (12345_8.000_ 12.000). The river miles are measured from the mouth, at the Pennsylvania boundary, upstream to the headwaters. This layer has more complete Strahler Order information.
Description: This layer represents the streams/rivers in the NHD that intersect Pennsylvania. The National Hydrography Dataset (NHD) is a feature-based database that interconnects and uniquely identifies the stream segments or reaches that make up the nation's surface water drainage system. NHD data was originally developed at 1:100,000-scale and exists at that scale for the whole country. This high-resolution NHD, generally developed at 1:24,000/1:12,000 scale, adds detail to the original 1:100,000-scale NHD. (Data for Alaska, Puerto Rico and the Virgin Islands was developed at high-resolution, not 1:100,000 scale.) Local resolution NHD is being developed where partners and data exist. The NHD contains reach codes for networked features, flow direction, names, and centerline representations for areal water bodies. Reaches are also defined on waterbodies and the approximate shorelines of the Great Lakes, the Atlantic and Pacific Oceans and the Gulf of Mexico. The NHD also incorporates the National Spatial Data Infrastructure framework criteria established by the Federal Geographic Data Committee.
Description: This layer represents the surface water areas such as river footprints, in the NHD that intersect Pennsylvania. The National Hydrography Dataset (NHD) is a feature-based database that interconnects and uniquely identifies the stream segments or reaches that make up the nation's surface water drainage system. NHD data was originally developed at 1:100,000-scale and exists at that scale for the whole country. This high-resolution NHD, generally developed at 1:24,000/1:12,000 scale, adds detail to the original 1:100,000-scale NHD. (Data for Alaska, Puerto Rico and the Virgin Islands was developed at high-resolution, not 1:100,000 scale.) Local resolution NHD is being developed where partners and data exist. The NHD contains reach codes for networked features, flow direction, names, and centerline representations for areal water bodies. Reaches are also defined on waterbodies and the approximate shorelines of the Great Lakes, the Atlantic and Pacific Oceans and the Gulf of Mexico. The NHD also incorporates the National Spatial Data Infrastructure framework criteria established by the Federal Geographic Data Committee.
Description: This data set represents the extent, approximate location and type of wetlands and deepwater habitats in the conterminous United States. These data delineate the areal extent of wetlands and surface waters as defined by Cowardin et al. (1979). Certain wetland habitats are excluded from the National mapping program because of the limitations of aerial imagery as the primary data source used to detect wetlands. These habitats include seagrasses or submerged aquatic vegetation that are found in the intertidal and subtidal zones of estuaries and near shore coastal waters. Some deepwater reef communities (coral or tuberficid worm reefs) have also been excluded from the inventory. These habitats, because of their depth, go undetected by aerial imagery. By policy, the Service also excludes certain types of "farmed wetlands" as may be defined by the Food Security Act or that do not coincide with the Cowardin et al. definition. Contact the Service's Regional Wetland Coordinator for additional information on what types of farmed wetlands are included on wetland maps.
Description: Temporay HUC layer for Tom Densilinger for use with the raindrop tool unitl the Watershed Boundayr Dataset release the formal 8-12 HUC boundaries for PA. 7/6/2006