SWMM 5.2 not issuing warnings/errors for incompatible pairs of conduit cross-section and inlet types #104
Description
The compatibility of conduit cross-sections and inlet types in SWMM 5.2 is as follows:
- Grated, curb opening, and slotted drain inlets can only be used by Street conduits.
- Drop grates and drop curb inlets can only be used by Open Rectangular or Trapezoidal conduits.
- Custom inlets can be used in any conduit.
The issue is that if you create an .inp file with a wrong pair of conduit-inlet (e.g., a Street conduit with a drop grate inlet), SWMM will run without issuing a warning or an error identifying this incompatibility. Instead, it will just not compute any captured flows by the inlet (i.e., they will be zero). In the GUI, this is displayed as empty cells in the Street Flow Summary table, similarly to compatible pairs with computed captured flows equal to zero.
You can actually produce such .inp file within the GUI, by assigning a compatible conduit-inlet pair (e.g., a Street conduit with a custom inlet), and then editing the assigned inlet to an incompatible inlet type (e.g., changing the custom inlet to a drop grate inlet) in the Inlet Structure Editor. As long as you do not open the problematic conduit in the map before saving and running, you will have an .inp file as described.
I think the engine should check for this type of incompatibilities before running, issuing an error if found.