Most of the water within CC's is maintained at a level considered most suitable for waterfowl purposes. During the summer months, most "pools" will just be mud flats. Water will get pumped in from the river during fall, but it's never very deep.
Water levels within CC may have little to nothing to do with river levels, as each "pool" has its own water-level mechanics.
Also, most of the pools have a narrow mechanically "dredged" center which tends to fill with silt. Can be very dangerous if you wade into the dredged area, when your next step in a 1-ft water level suddenly places you waist-deep in silty mud. Ask me how I know.