Model alternatives consist of input data sets and configurations for each model. Model alternatives configurations do not include time-specific data. Therefore, model alternatives can be used in conjunction with any time window.
In general, models and their alternatives are created using the software of the native model, for example, HEC-HMS, HEC-ResSim, HEC-RAS, and HEC-FIA. Once models and the alternatives created and configured initially, the model alternatives are imported into the watershed using the import commands in the File menu of the Setup module. The model alternative import process is detailed in Importing Watersheds and Model Alternatives. Once imported, model alternatives can be configured and edited in the HEC-RTS interface.
HEC-RTS uses plug-ins that allow interfacing with the software programs of the native model. This means that all aspects of model alternatives are configurable using the native model interface of HEC-RTS. For example, you can edit HEC-HMS base model parameters directly using the HEC-HMS software.
MFP deals with observed meteorological data and future precipitation. You can configure MFP model alternatives for use in conjunction with HEC-HMS to compute a variety of observed or future precipitation scenarios. An HEC-HMS model alternative simulates watershed response to precipitation. You can use HEC-HMS Model alternatives to forecast future flows. An HEC-ResSim model alternative assists with reservoir operations, consisting of the physical data representing a river-reservoir system and operating rules for all controllable elements in the system. HEC-RAS model alternatives describe water surface profile and stages at gage locations, geometry information for a river, and defined flow data sets. An HEC-FIA model alternative allows you to analyze flood consequences. HEC-FIA model forecast alternatives are a combination of impact areas and hydrograph time series sets. You can edit the parameters within each model alternative to reflect changing conditions.