I have a few infiltration basins and an underground storage chamber system. They are not connected and in each of the watersheds the storage is greater 100-year rainfall volume. In two of the watersheds, I am getting a positive peak flow number. When I check in the pond outlets, the total outflow is higher than the exfiltration. The peak flow cfs seems to be representing the difference between the total outflow and the exfiltration. If my max elevation never gets to the top of my storage, what is the outflow that is appearing and how do I get resolve it to be zero as it should be.
