Single Loss Method for EPA-SWMM Catchments
In CivilStorm and SewerGEMS when using the EPA-SWMM Runoff Method the loss method used must match the same infiltration method specified in the calculation options.
The option is labeled as "Default Infiltration Method" and has the following options:
The corresponding loss method options on a catchment are:
The validation checks all active catchments for the scenario being computed and then filters the list further for those that are EPA-SWMM Runoff Method with a loss method not equal to the setting in the calculation options.
The reason for this validation is simple. SWMM only supports the calculation of a model using a single infiltration method. All catchments will use that one global infiltration method with no local overrides.
If a model has a condition where an EPA-SWMM Runoff Method catchment uses a loss method that is NOT the same as the calculation option, the following user notification is generated:
-1 "Base" "Scenario "1" "Base" (N/A) "One or more EPA-SWMM catchments are using an infiltration method not the same as the default infiltration method in the calculation options." Precalculation
This user notification is only generated when the engine type in the calculation options is set to "Implicit" (which is the Bentley DynamicWave calculation engine).