Gates will give you water, but just as easily they will shut it out.
There’s no better example than the Everglades S-11s.
This year’s total is 500,000 acre feet (so far), with about a month of flows to go.
The wetland water table is already too high to the south, so all things being equal, there’s a desire not to send more. To the north water is needed keep the wetlands hydrated and the shallow water table recharged for the long dry season to come.
That makes the “River of Grass” bigger than a creek (nearby Fisheating Creek averages 270,000 acre feet per year) but unmistakably engineered.