Good afternoon.
I am currently working on a dam failure analysis. The dam is on a very small stream and very shortly (about 700lf) downstream of the dam this stream discharges into a much larger river with a very large floodway area. Floodway width is about 6,000lf. When I model this situation and try to carry the model into the larger floodway my flows increase in every cross section in the larger floodway. Where does the extra flow come from in RAS/why is it doing this? I am guess I have too little flow (270cfs) for RAS when the flood wave from the little stream hits the big floodway RAS freaks out and adds a lot of flow. Any thoughts?
Thanks!
TG