use the RG gauge regardless of your putin/takeout. I have boated eveything down there several times, and have never taken a raft. Its always been a canoe trip. August is monsoon season, but hotter than hell of course. basically, you need your gear loaded, and need to be able to GO NOW, when it rains in Northern Mexico for it to be a viable raft trip.
colorado canyon has the best gradient/current of anything out there, and i would suggest combining colorado canyon/santa elena canyon into a 5-6 day trip. have fun
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