What will happen is, at a higher water level, this extra conveyance capacity that exists in the river will allow water to flow out quicker, but once it drops down to the current water level regime, the outflow is within less than 1% of what it was before the erosion and dredging occurred, because the water levels are lower.
It doesn't play to a quick five-minute answer. It's a little more complicated than that. I think simplifying it too much actually does a disservice to the actual science that is very well established—