You picked a great time of year for your first visit. Lots of good advice given here on things to see and do. I agree with all of it and won’t add more. We usually start with a fixed campsite and then use our SeaDoo to take long trips during the day. You will be surprised to see how short a week becomes on Powell.
I think we all started with the suggested Stan Jones map from years ago, which offers a lot of info. Once your addicted, pick up a copy of Michael Kelsey’s book on hiking Powell. Just double the allotted times he gives. The whole lake is like no other, there are only varying degrees of “amazing”. Maybe I missed it, and it sounds like your mapping software is sophisticated, but beware that Lake Powell has areas with hidden “whales” or reefs in places you would never expect to find them...like in the middle of a large bay or middle of an apparently deep channel. Keep an eye out for the green water. Driving into the sun or choppy water can make them hard to see. Polarized glasses obviously help. The main channel is marked with atons and occasional cigarette buoys, but historically poorly maintained. I would suggest following the marked deep water channel atons or the main river channel on your GPS until you become familiar with the corners that can be cut etc. I like laying down a good, safe, saved GPS track going uplake that can be reasonably followed should an emergency require a trip out at night or driving into the setting sun. No side canyon is officially marked, but beware of floating gallon milk jugs in the side canyons as they are usually marking a hazard. Someone suggested a tour up West Canyon, which is great, but many of my low water year memories of west are littered with an abundance of underwater hazards, especially near the entrance, many marked by boaters with the milk jugs.
Unless something has changed this season, know that all the fuel sold on the water is alcohol fuel. I carry the Starbrite fuel additive for use on the Lake. Historically we use the Sinclair at the top of the hill in Page for non alc fuel. I think I heard that Maverick also had it available last year.
Many fall trips we find groups of C Dorys on the lake. Usually seems like September, but I’m linking to a YouTube of a gathering last August. In addition, a link RE Powell on a C Dory site. Enjoy your trip!
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