I've just started doing some testing of the Beta SWMM5 and the only computational problem I've come with in the limited time that I've had with it is,

1. Inputting rainfall records thru TIME SERIES, the model is not correctly reading the rainfall time series as continuous rainfall. Rather, it is reading the rainfall as "spikes" at each of the time increments read. This seems to happen whether continuous or incremental records are read in. This of course results in nonsense multiple spikes in the hydrographs generated for each subcatchment and routed thru the system.

Noel S. Atkisson, P.E.
n.atkisson@dannembaum.com