I am currently using SSA 2018 which seems to be using an outdated SWMM 5 version (I can't find what SWMM version it is actually using within the program). I've run my model through the latest EPASWMM software and my results show about a 20% reduction in peak flow in a canal with the latest SWMM version.
Is there a way of checking and updating the SWMM engine within the SSA software that I have?
