I have a real storm water case study where the storm water cannot enter the minor sewer system and remain on the surface due to insufficient inlet capacity.
I am modelling it with ICM and the catchments are connected to the manholes thus the storm water goes directly to the minor system and only floods into the 2D overland mesh in case of sewer surcharge.
Is there any possibility for the runoff from the catchments remain on the 2D overland mesh if the inlet manhole do not have capacity?
I tried already all the manholes "Flood types" and believe that the catchments must be directly connected to the manholes and the alternative I have is to forget the catchments and apply the rainfall directly to the 2D mesh.
Any suggestion?

Thank you!

Rui Pina