[Borys]

I am trying to model the hydraulics of highway ditches system.
Problem is that my subbasin length is the same as channel length; I have no inflow except lateral flow created by road, and I need to see what flow will be in the ditch.

I created open channel presenting median of highway including left and right lanes and shoulders. How I need to tie-in subbasin to have lateral flow?

Or is there any other way to do it?