The Modeling module for CWMS is the grouping of commands for model execution. These include commands for creating and managing forecast alternatives, editing selected model parameters, executing alternatives, and evaluating results.
Figure 1 displays the flow of data and information through the CWMS analysis applications. CWMS uses six standard analysis applications: the meteorological preprocessor MFP, the watershed runoff model HEC-HMS, the reservoir simulation model HEC-ResSim, the hydraulic routing model HEC-RAS, and the flood consequences analysis model HEC-FIA. These analysis applications and their inputs and outputs are described in Modeling Module Overview.
The meteorological preprocessor MFP, combines observed precipitation data and future precipitation information into a single precipitation dataset that can be used by the watershed runoff model (HEC-HMS). Using the observed and future precipitation from a meteorological preprocessor (MFP), HEC-HMS computes runoff. HEC-ResSim uses uncontrolled flows (typically computed by HEC-HMS) as input and simulates reservoir releases. In turn, controlled flows (computed by HEC-ResSim) are used as boundary conditions to the hydraulic routing model HEC-RAS. (HEC-RAS can also use flows computed by HEC-HMS or supplemental models as input). HEC-RAS computes stage, which is input to HEC-FIA. HEC-FIA analyzes flood consequences. (HEC-FIA can also use flow computed by HEC-HMS, or HEC-ResSim as input.) Results include impact and action reports from HEC-FIA, inundations maps that can be viewed with RAS Mapper (tool that is part of the HEC-RAS software), and simulated release schedules from HEC-ResSim.