The Hydrologic Engineering Center (HEC) has replaced the HEC-1 analysis program with the HMS program. HMS includes most of the same capability as HEC-1, but has dropped some of the lesser used functions and added others. You can use WMS to delineate watershed data and define most parts of the HMS model. The Export HMS Basin File found in the HEC-1 menu will create the input file necessary to use data derived in WMS to perform modeling in HMS.
There are five different files that are (or can be) exported as part of the HMS simulation.
The Project file is like the WMS super file in that it is used to keep track of the other files that make up the HMS simulation.
The Control file includes the job control data, or simulation global parameters such as time step, number of ordinates, id cards, etc.
The Basin file has all of the parameters for each hydrologic unit (basin, outlet, diversion, etc.).
The Precipitation file contains the information used to define the precipitation event for the simulation.
The Map file is a map or trace of the watershed and sub-basin boundaries. It is not a terrain model and therefore cannot be used to extract information such as area or runoff distance; it is only a "picture" of the watershed that is placed as a backdrop to the HMS schematic. If you have a watershed derived in WMS from a digital terrain model then you can export it as part of your HMS project. In order to export the map you must convert it to feature objects. If you create your watershed from feature objects or a DEM then it will already be in this format. If you create your watershed from a TIN then you will need to use the Drainage Data -> Feature Objects command found in the Drainage menu prior to exporting your HMS files.
Related Topics:
Saving HEC1 Files
Running an HEC1 Analysis