The Hydrologic Modeling System (HEC-HMS) is designed to simulate the complete hydrologic processes of dendritic watershed systems. The software includes many
traditional hydrologic analysis procedures such as event infiltration, unit hydrographs, and hydrologic routing. HEC-HMS also includes procedures necessary
for continuous simulation including evapo-transpiration, snowmelt, and soil moisture accounting. Advanced capabilities are also provided for gridded runoff
simulation using the linear quasi-distributed runoff transform (ModClark). Supplemental analysis tools are provided for model optimization, forecasting streamflow,
depth-area reduction, assessing model uncertainty, erosion and sediment transport, and water quality.
The software features a completely integrated work environment including a database, data entry utilities, computation engine, and results reporting tools.
A graphical user interface allows the user seamless movement between the different parts of the software. Simulation results are stored in HEC-DSS (Data Storage
System) and can be used in conjunction with other software for studies of water availability, urban drainage, flow forecasting, future urbanization
impact, reservoir spillway design, flood damage reduction, floodplain regulation, and systems operation.