WinHSPF uses a series of files from BASINS for creating a new project. These files are intended to be produced using the BASINS GIS interface, but since they are text files, they may be built manually. Once a new project has been created, these files will no longer be needed by the project.
The following sections provide detailed descriptions of each of these files and their contents. For examples of these files, see BASINS File Samples within the Appendix. The following is a list of the files:
Watershed File - *.wsd
Reach File - *.rch
Channel Geometry File - *.ptf
Point Sources File - *.psr
The Watershed File has a .wsd extension. This file contains information related to the amount of each land use contributing to each reach. This file is written from BASINS and is used in creating a new WinHSPF project.
The Watershed File is a space-delimited ASCII file, with one or more spaces used to separate fields. Each record of the file contains the following information:
LU Name (land use name, used as LSID in PERLND/IMPLND GEN-INFO table)
Type (1=impervious/2=pervious, used to specify PERLND vs IMPLND)
Watershed-id (used to connect each land use to a reach)
Area (in acres, used as area factor in SCHEMATIC block)
Slope (used as SLSUR in PERLND PWAT-PARM2/IMPLND IWAT-PARM2 table)
Distance (in ft, used as LSUR in PERLND PWAT-PARM2/IMPLND IWAT-PARM2 table)
An example of the Watershed File is found in the Watershed File section of the Appendix.
The Slope and Distance fields are derived from the fields ‘Slo1’ and ‘Len1’, respectively, in the Subbasins shape file. These values are computed during watershed delineation.