Available stormwater models and selecting a model
Hydrologic, hydraulic, and water quality models all have different purposes and will provide different information. The tables below summarize some of the commonly used modeling software and modeling functions and the main purpose for which they were developed. The tables show the relative levels of complexity of necessary input data, indicates whether the model can complete a continuous analysis or is event based, lists whether the model is in the public domain, and for hydraulic models indicates whether unsteady flow calculations can be conducted. For water quality models, the tables indicate whether the model is a receiving waters model, a loading model, or a BMP analysis model. The following definitions apply to the model functions.
- Rainfall-Runoff Calculation Tool: peak flow, runoff volume, and hydrograph functions, only. More complex modeling should utilize hydrologic modeling which incorporate rainfall-runoff functions.
- Hydrologic: includes rainfall-runoff simulation plus reservoir/channel routing.
- Hydraulic: water surface profiles, flow rates, and flow velocities through waterways, structures and pipes. Models that include Green Infrastructure typically also assess how the BMPs managage the water through inflow, infiltration, evapotranspiration, storage and discharge.
- Combined Hydrologic & Hydraulic: rainfall-runoff results become input into hydraulic calculations.
- Water Quality: pollutant loading to surface waters or pollutant removal in a BMP.
- BMP Calculators: spreadsheets that predict BMP performance, only.
Classification of models by model type