Utah Whitewater Club
Finding serious (i.e., folks who actually go and paddle) boaters is more hit or miss in the intermountain west for a lot of reasons, including the distances involved getting to/from decent whitewater. The Weber below Henefer (to Taggarts and beyond) is closest fun stuff, Class II at best (unless releases are over 2k, which has been rare since 2011) - it's little over an hour from SLC but a tube-filled mess on summer weekends (think LDS teens and 20-somethings with beer coolers, sometimes accompanied by frowning parents...). There's a "play park" lower down in Ogden but it also needs water to be worth the trip.
Westwater is 4-5 hours and well worth it, but only 3 miles of rapids in the 16 miles from the ranger station to Cisco.
Cat is big fun but at least a 4 day trip even putting in at Potash - and 16-18 miles of rapids in the 94 miles down to North wash.
Then there's Idaho...
Point is SLC is a great place to base but it's a long way from the big fun for serious paddlers. So most trips tend to be multi-day, not a bad thing but different from east coast scene with lots of day trip options. You can PM me for more info but I'm retired from paddling, float and bloater now but still out there.