I am running a model using hydrodynamic for linking routing, with a routing of 1 sec and lengthening time step of 100, variable time step checked and safety factor of 75%. No matter what factors I change (i.e. routing, time step, safety factor), the inflow hydrographs show a spike in inflow at the beginning of the simulation. I have even tried using a user defined hydrograph with zero intensity for the first 10 hours and still, the inflow hydrograph (with hydrodynamic) still shows a flow. Where is this flow coming from and why is it happening?
When I run kinematic, the inital spike does not occur....the inflow hydrograph spikes with the user defined hydrograph.
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