Selecting Inputs¶
Each scenario references a specific set of inputs. Changing inputs creates a new scenario variant without modifying the original data.
Required inputs¶
Every scenario needs at minimum:
- Elevation: the DEM raster
- Boundary: domain boundary lines
- Inflow: at least one rainfall polygon or surface flow line
Optional inputs¶
| Input | Effect if omitted |
|---|---|
| Friction | Default Manning's n (0.04) applied everywhere |
| Structures | No buildings (flat terrain only) |
| Mesh Regions | Uniform mesh resolution across entire domain |
| Catchment | No hydrological routing |
Comparing scenarios¶
You can create multiple scenarios within a project, each with different inputs or parameters. This is useful for:
- Sensitivity analysis: vary one input at a time
- Design comparison: test existing vs proposed conditions
- Climate scenarios: run different rainfall intensities