GeoHECHMS can simulate and analyze the hydrologic processes of a watershed. The common HEC-HMS workflows performed in GeoHECHMS are flexible and can be adapted to address specific hydrologic modeling needs based on the characteristics of the study area and the objectives of the analysis.
Following are some common workflows that can be performed using GeoHECHMS:
- Watershed Delineation
Based on topographic data and digital elevation models (DEMs), GeoHECHMS can delineate the boundaries of a watershed. This process helps in defining the spatial extents of the study area.
- Rainfall-Runoff Modeling
GeoHECHMS allows users to develop rainfall-runoff models to simulate the response of a watershed to precipitation events. It can incorporate various methods such as the Soil Conservation Service (SCS) Curve Number method, Unit Hydrograph theory, etc., to estimate runoff volumes and hydrographs.
- Flood Routing
GeoHECHMS offers flood routing capabilities to simulate the movement of water through river channels and reservoirs. It can utilize different routing methods like Muskingum-Cunge, Muskingum, and Lag routing to analyze the propagation of flood waves.
- Reservoir Operations
GeoHECHMS allows for the simulation of reservoir operations, including storage routing, flood control analysis, and determination of release patterns based on inflow forecasts, operating rules, and constraints.
- Design Storm Analysis
GeoHECHMS automatically determines the design storm and corresponding precipitation based upon the project location anywhere within the USA, Canada, Austria, and Germany. It will determine the design rainfall for the 1, 2, 5, 10, 25, 50, 100, and 500-year storms by querying the Precipitation Frequency Data Server based on the project location.
- Scenario Analysis
GeoHECHMS facilitates scenario-based analysis by allowing users to evaluate the effects of various factors on the hydrologic response. This may involve investigating the impacts of land use changes, infrastructure development, etc.
In GeoHECHMS, different types of outputs help users to understand watershed behavior, evaluate the performance of hydrologic models, support decision-making processes related to water management and infrastructure design, etc.
Following is the list of common outputs that GeoHECHMS can generate:
- Time series hydrographs of streamflow or discharge at specified locations within the watershed.
- Peak flow rates and timing.
- Rising and falling limb characteristics of the hydrographs.
- Hydrograph comparison plots for multiple scenarios.
- Storage-Discharge Curves
- Relationship between reservoir storage levels and corresponding outflow or discharge rates.
- Spillway discharge rates and corresponding water levels.
- Infiltration Losses
- Quantification of infiltration losses from rainfall.
- Depth of water infiltrated into the soil.
- Infiltration rates and their variation over time.
- Runoff Hydrographs
- Simulated hydrographs representing the flow of water in rivers or channels.
- Peak flow rates, timing, and duration.
- Baseflow and direct runoff separation.
- Reservoir Operations
- Reservoir storage levels and variations over time.
- Reservoir releases and outflow rates.
- Spillway discharges and flood routing through the reservoir.
- Project Summaries
- Summary statistics (i.e., Generated Report) of simulated results, such as peak flows, volumes, durations, and lag times.
- Error measures for comparing simulated and observed data.