Hello, I have a SewerGEMS model set up to review 2, 10, 100, and 2500 year storm scenario's. For this model, the explicit solver achieved much better convergence and continuity error results for the 2, 10, and 100 year storms. However, I am seeing very poor results currently when running the 2500 year storm. This storm event results in a few of the catch basins having "overflow" which I think could be a portion of my problem.
The 2500 year storm has to be run so that I can look at the ponding results at the various flooding catchments and verify that the ponded depth does not impact nearby roads/facilities. I am new to reviewing this ponding depth and would be open to any suggestions on how to best set up and review this portion of the model.
Another aspect of the model that appears to be incorrect is the maximum inflow/outflow for each of Basin A and Basin B. 50-60cfs for each basin outflow is expected for each and that roughly appears to coincide with what the flow in the outfall pipes is. However, the pond flex table shows a much larger number for the outflow. Basins A and B also are showing much larger than expected inflows. When running the hydraulic reviewer volume balance on the ponds, the reviewer shows a huge difference in inflow volume vs. outflow volume. I am not sure if this could be related to the overflowing inlets or not, but I am 100% sure on what steps to take next to troubleshoot this model. The problems all seemed to start arising as soon as some flooding of the inlets began happens in the 2500-year event as the other rainfall event have little issue. I have attached the model for reviewing.
7002.New folder.zip