Canyons are inherently risky. Flash floods occur without notice on sunny days. Technical skills & surrounding topography knowledge required yet does not eliminate risk.
Easy intro to Ouray Canyons
Overview: A canyoneering trip into one of Ouray's easier canyons
Warning: Always check the weather before going and do not enter the canyon if there is a reasonable chance of any rain and flash flooding danger. For this trip, you will need a helmet, harness and rappelling gear, including enough rope for a 50 ft rappel. In light flows a wetsuit is not necessary for advanced canyoneers but you may get wet to the knees. Inexperienced rappelers may get soaked in cold water and desire the wetsuit.
Danger: It is inadvisable to do any of Colorado's canyons other than in late summer/early autumn. The spring thaw flows can be violent and dangerous. After a heavy winter Colorado canyons may be more difficult than described here due to heavy flows.
History: Published in Michael Dallin's book "Ouray Canyoning".
Hike: You must park at the road by the bridge, from here hike up the campground road, turning left onto the better road until you head up the mountain onto what becomes a trail. Hike about 300 ft vertical elevation gain (about half a mile) until you see a decent trail heading down into the drainage at a flat spot in the creek before it tumbles over a cliff (38.00789,-107.69623).
From here gear up and descend the watercourse. The first rap is 30 ft from 2 bolts, followed by some downclimbing through pools.
I think there is a short rap next, though my memory is poor.
After this there is another rap from two bolts on right, perhaps 40 ft. Try not to saw your rope. Downclimb through the next pools.
You will rock hop downstream perhaps a quarter mile.
At the end there is an optional 8 ft rappel or else downclimb out of the flow on right LDC.
After this look for fixed ropes leading up a steep ridge/fin on right looking down canyon, climb up and out here. (If you reach the intersection with the large creek you have gone too far.) This section may be scary for people not comfortable with climbing crummy slopes with exposure. This is the least pleasant part of the trip. When you reach the top, take the trail back down to the campground and walk the road straight (passing by the intersection you turned when heading into the canyon) and follow the road back to your car.
You can lap the canyon several times in the day or else add something else to the itinerary. By itself this canyon trip doesn't have much meat on its bones. Be advised that the middle section of Angel is supposedly much more difficult. This author has yet to try that part.
Water Sources: Bring enough with you or else filter when you get there.
Camping: The campground you hike through has camping, if available.
Check out the Official Route and Triplogs.