I have a storage area defined by an elevation-volume curve connected to a 2D area via a SA/2D area connection (embankment) with a culvert through the embankment serving as the low level outlet pipe. If I set the starting elevation for the reservoir (in the Unsteady Flow Data editor initial conditions tab) at an elevation below the culvert invert (e.g., culvert invert at 3305 and set starting elevation at 3303 ft) and run the simulation, the stage in the reservoir increases and there is flow through the culvert. However, if I set the starting elevation well above the culvert invert (starting elevation at 3380 ft), the stage in in the reservoir increases but there is no flow through the culvert. By trial and error, I determined that there is flow through the culvert up to an initial elevation of about 3375 ft but no flow after that. Any suggestions on how to fix this or on why it is not working correctly would be greatly appreciated.