Boundary Conditions for SWQ¶
SWQ boundary conditions define domain of validity for the actual boundary condition (surface runoff or RDII) and the boundary condition spatial extent.
Figure: The Boundary Conditions editor showing Types relevant for SWQ
SWQ Boundary Condition Types¶
SWQ boundary conditions are of the following types (see figure above):
- Stormwater Loads (Surface). This type applies for WQ in surface runoff.
- Stormwater Loads (RDII). This type applies for WQ in RDII flows.
The table below provides an overview of the SWQ methods that are applicable under the two types of stormwater loads (surface runoff and RDII), i.e. with the two types of SWQ boundary conditions.
| Hydrological model/combination | SWQ Boundary condition and SWQ methods | |
|---|---|---|
| Stormwater loads (surface) | Stormwater loads (RDII) | |
| Time-Area | Methods 1, 2, 3, 4 | - |
| Time-Area + RDI | Methods 1, 2, 3, 4 | - |
| Kinematic Wave | Methods 1, 2, 3, 4 | - |
| Kinematic Wave + RDI | Methods 1, 2, 3, 4 | Methods 1 ,2 |
| Linear Reservoir (C1) | Methods 1, 2, 3, 4 | - |
| Linear Reservoir (C1) + RDI | Methods 1, 2, 3, 4 | Methods 1 ,2 |
| Linear Reservoir (C2) | Methods 1, 2, 3, 4 | - |
| Linear Reservoir (C2) + RDI | Methods 1, 2, 3, 4 | Methods 1 ,2 |
| UHM | Methods 1, 2, 3, 4 | - |
| UHM + RDI | Methods 1, 2, 3, 4 | Methods 1 ,2 |
| RDI (solo) | - | Methods 1 ,2 |
Table: Overview of applicable SWQ boundary condition types and SWQ methods for various hydrological models and their combinations. All surface runoff models support all four SWQ methods, while RDI supports only Method 1 (Simple Concentration) and Method 2 (Tabulated concentration).
Spatial Extent¶
As any other boundary condition, SWQ Boundary Conditions may be specified as uniform for the entire model (i.e. associated with all model catchments), or as spatially distributed through selections of catchments and/or individual catchments.
The figure below illustrates definition of spatial extent based on a list (selection). Note that selections may refer to different geographical areas as well as to different catchments layers.
Figure: Example of a Stormwater Loads (Surface) boundary condition with spatial extent defined by a list (selection) of catchments (roof_catchments)