One Second View of a Pump Event in InfoSWMM / SWMM5

How does a pump turn on with a one second time step?
1. Pump On depth is reached in the Wet Well
2. The pump sees the head across the pump and calculates the flow from the pump curve
3. The head gain decreases after the pump turns on as there is now more flow in the force main and an increased depth and head at the downstream node
4. The pump in a short period has a constant flow as the head gain across the pump stays constant.
5. The pump has small spike at the beginning of the pump event due to the changing of the pump head gain.

One Second View of a Pump Event in InfoSWMM / SWMM5

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