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NSI Hydrography Network for SSN Analysis (shapefiles)

Shapefiles of the NSI network are available here for download by NHD production units; as are shapefiles of prediction points that can be used to make predictions at unsampled locations and map the results of SSN analyses. Each shapefile has specific metadata, but for general metadata see the General Flowline Metadata document or the Prediction Points Metadata document. A comprehensive description of the technical procedures applied to the NHD-Plus hydrography layer, as well as additional steps that are required to prepare datasets for SSN analysis are described in the NSI User Guide.