The river level fluctuates, sometimes high, sometimes low enough that you'll wish your boat was flatter and had less draw. A lifejacket is also a necessary item on this mighty river. If you wade, wear neoprene waders in this cold tailwater. If you don't use a high-density sinking line, use heavily weighted nymphs. Spincasters have good luck on the Colorado with jigs and spinners.
Some anglers use strike indicators.
In the spawning season, fishermen often sightcast to big schools of rainbow trout. Spin fishermen should work the numerous deep pools. The river fluctuates so often that the best lies change from hour to hour. With this kind of complexity, the first time or first few times you fish the river, it is best to hire a guide. Below the Paria River, the fishing isn't very good due to mud and silt, but this area is one of the better places on the river to wade fish.