You can try here:
There's not too much info on the local runs there.
Here's the run down of my favorites. (Keep in mind, our motto is central to everything close to nothing, which means you're gonna be driving -- a lot.) I'll list them by proximity.
I'll skip the weber as it's probably on that site.
The Provo offers a couple of good creek sections up in the Uintas. There's Provo falls which is a nice park and huck option in the spring. Below there, Slat Gorge an the Box Canyon offer some nice class IV+ runs with steep slides, waterfalls or two and a few logs. In a good year, it goes for maybe a month. Near Provo, there's the class III- IV Bridal Veil run that, when there's water offers a good afterwork experience. (1-1.5 hours to Uintas, 0.5-0.75 to Bridal Veil)
Sixth Water creek in Utah county offers another park and huck (plop and drop) experience. Some folk's really like it. It's kind of a bitch of a drive. The completion of the Diamond Fork project shut off the celestial gorge run that used to be bellow the Syar tunnel. I've heard recently that this is still fun with the decreased flows. (2 hours.)
On the Wasatch Plateau, Cottonwood Creek (Seeley creek) offers some beautiful class III(IV) when Joe's Valley Dam release more than 300 cfs. It's pretty fun, and the water's beautiful. Good for a short weekend. (2.5 to 3 hours) Also in the area is the left Hand Fork of the Huntington. It's kind of hard to catch with much water, but when the combined releases from Miller's Flat and Cleveland are > than 125, it's a fun run.with some cool slides, three ledges, and lots of wood. There's some other obscure desert rivers further south like the escalante, Boulder Creek, Fremont and Ferron creek. They're pretty hard to catch with enough water and offer everything from mellow float trips through beautiful canyons to fairly unique creeking.
Westwater's 4 hours away and there's already lots of info about it on the buzz.
Going North: The Ogden is .5 hours away and offers a great run when they release enough water from Pineview. It's good at 400 cfs and great at 700 cfs. Class IV in the canyon and II-III below there.
The Logan and the Cub are about an hour north. I've not run the Cub, but some folks speak highly of it. The Logan itself offers a full range of runs from II-IV+.
The Black Canyon of the Bear ( about an hour from SLC) is good when there's water. AW negotiated a recreational flow study that was supposed to provide weekend releases starting around 2006. This might have been pushed back due to the ongoing drought. Check with them. It's really fun at 1000 cfs.
In Southern Idaho, the Blackfoot offers pretty reliable creeking (IV-V depending on the boater) through the summer (except for this past year) on a 7 miles stretch. It's one of my favorites and is a long day from SLC (3 hours from my house to the putin) or a nice short weekend with mutliple runs. Also in the area are is the Teton and Bitch creek. I like the Teton better (shorter, less wood), but they're both worth running.
I guess the Alpine Canyon section is also in the same direction, and is about the same distance. Lots of Utah boaters make this a weekend destination as it offers a good play run, and two good creeky runs on the Grey's and the Gros Venture (I butchered that spelling -- sorry). The Hubacks up there too and is class II(III).
Going towards Twinfalls, there's the Murtagh Section of the Snake (3.5 hours). This also used to be a great reliable summer run, but has been hampered by the draw-down of the reservoirs along the Upper Snake. It's a really fun class IV play run with quality rapids and a couple good play spots. personally, I like flows down around 1500 when the river is confined to it's inner channel.
I'm sure I've forgotten a few runs. But for the most part, everything else is pretty much in someone else's backyard so they're better situated to comment. I can be in the Payettes in 7 hours (I drive slow), Western Colorado in 5-6, to the putin for Giant Gap in 8-9. ( I said there'd be lots of driving.) With all that said, you're the JD in California right? I don;t think anything in the state of Utah approaches the quality of runs in California (or Colorado for that matter). So, in that regard you'll be disappointed with SLC as a paddling city. The Skiing is pretty good though, and well, you're central to everything. Drop me line if you want more info:
edward.clark AT gmaildot com.