Here is all the info that you need..
The bottom guage is fine but unless you know what the tunnel is doing you dont know what is going to be in there..
Right now as bob said laps of the cauldron, brains, or the paralyzer will go but that is about it.. I like at least 350 to 400 cfs in there for a down stream run.. A few days last week it got that high in the AM but they are not pumping in the afternoons so plan on low water..
Also you can tell from the guage but the level can, will, and does change up to 400 cfs in a matter of min...