PRMS allows for multple parameter files that are associated with the same model, for example one file may contain the dimensions and parameters associated with soil properties and another may contain the parameters for the snow module, another for cascading flow, etc. A similar thing can be done with data files: one file can contain ten stations where precip was recorded and another file can contain tmin and tmax. An example of multiple data files is the ACF model included in the PRMS download from the USGS, the sagehen model they provide has multiple param files. The files are listed in the control file for example in the sagehen model the parameter files are listed in the control file like so:

####
param_file
6
4
./input/sagehen.params
./input/gis.params
./input/gvr.params
./input/ncascade.params
./input/ncascdgw.params
./input/subbasin.params

When we tackle this issue we will need to consider that the Parameter object needs to connect to all the param files listed in the control file. One idea is to use the control file on Parameter/Data initialization to connect all the corresponding files. The simulation class will need to include the appropriate collection of input files which can be ideally handled by only modifying the Parameter class.