ICM InfoWorks - ๐ง️ Runoff Volume Models
๐ง️ Runoff Volume Models
๐ Runoff volume models in InfoWorks help determine the amount of rainfall ๐ฆ️ that transitions into the drainage system ๐ฟ, considering initial losses ๐ง.
๐ง Set the Runoff Volume Model within the Runoff Volume Type field of the Runoff Surface. This surface then links to one or more Land Use objects ๐ฑ which connect to one or more subcatchments.
๐ค Surfaces of varying types might be combined in one model. Remember to set the correct initial conditions in the Rainfall Event for each surface type used.
๐ Runoff Model Overview
| ๐ # | ๐ Model | ๐ฆ Type | ๐ก Comments | ๐ Runoff Surface Data Fields Used | ๐ฅ Appropriate For |
|---|---|---|---|---|---|
| 1️⃣ | Constant Infiltration (ConstInf) | Individual | Set constant infiltration from surface to groundwater. | Fixed Runoff Coefficient, Infiltration Loss Coefficient | General usage |
| 2️⃣ | DefConLoss | Individual | Based on HEC-HMS model. | Maximum Deficit, Infiltration Loss Coefficient | Advanced hydrological modeling |
| 3️⃣ | f1-Rsa | Individual | Calculates effective rainfall using Quasi Linear Reservoir Method. | Minimum runoff, Maximum runoff, Saturated rainfall | Standard in Japan ๐ฏ๐ต |
| 4️⃣ | Fixed percentage runoff | Individual | You define the percentage of rainfall that becomes runoff. | Fixed Runoff Coefficient | When runoff percentage is known |
| 5️⃣ | Green-Ampt | Individual | Used only on pervious surfaces. | Green Ampt Conductivity, Green Ampt Suction, etc. | US with SWMM model ๐บ๐ธ |
| 6️⃣ | Horner | Individual | Determines net rainfall on urban subcatchments. | Horner Alpha, Horner Beta, Horner Recovery | Urban areas ๐️ |
| 7️⃣ | Horton | Individual | Used only on pervious surfaces. | Decay factor, Initial infiltration, etc. | Rural and pervious surfaces ๐ณ |
| 8️⃣ | HortonSWMM | Individual | Specialized for pervious surfaces. | Decay factor, Initial infiltration, etc. | Desbordes or SWMM models |
| 9️⃣ | New UK (Variable) PR | Total catchment | UK model for changing catchment conditions. | New UK Depth, API30 | UK pervious catchments ๐ฌ๐ง |
| ๐ | PDM | Total catchment | Requires PDM option enabled. | - | Specialized usage |
| 1️⃣1️⃣ | ReFH | Individual | Based on procedures by CEH. | ReFH Cini (rainfall event initial condition), ReFH BF0 | Most UK subcatchments ๐ฌ๐ง |
| 1️⃣2️⃣ | SRM | Total catchment | Requires PDM option enabled. | - | Specialized usage |
| 1️⃣3️⃣ | UKWIR | Total catchment | Uses UKWIR equation by HR Wallingford. | Effective impermeability, IF, etc. | UK catchments ๐ฌ๐ง |
| 1️⃣4️⃣ | USA Soil Conservation Service (SCS) method | Individual | A rural catchment model. | SCS Depth, SCS Index (rainfall event initial condition) | Rural catchments ๐พ |
| 1️⃣5️⃣ | Wallingford Procedure (Fixed) PR | Total catchment | Default model for the UK. | Fixed Runoff Coefficient, Wal. Proc Distribution | UK urban catchments ๐ฌ๐ง |
| 1️⃣6️⃣ | CN | Individual | Rural catchment model similar to SCS. | Curve number, SCS Index (rainfall event initial condition) | Rural catchments ๐พ |
| 1️⃣7️⃣ | DWA (Grenzwertmethode) | Individual | German initial loss and runoff model. | Decay factor, Initial infiltration, etc. | Catchments in Germany ๐ฉ๐ช |
| 1️⃣8️⃣ | CNSWMM | Individual | Developed by US EPA. | Curve number, SCS Index (rainfall event initial condition) | Rural and pervious surfaces ๐ณ |