Nearly every trail in Utah fits your description. Unless you are seeking out bigger stuff, aka a resort, you'll have a blast nearly everywhere. Park city? Yes. Corner Canyon? Of course. American Fork Canyon? Yep. And that's just some of the more popular areas in N. Utah.

 

You will find flowy XC trails in south Utah, which I highly recommend because it is super scenic. The centers of trail action are in the Hurricane / Zion National Park / St. George area about 2 hours north of Vegas on I-15 and on the east side of the state is the Moab MTB wonderland.

Utah Mountain Biking - Trails, Information, Repairs is a great source of information!

Near Hurricane is the Zen Trails for fast non-technical flow. Near Moab the Klonzo Trails would be good and also the new Chisholm Trail. Good to start on Lazy and Easy Trails at the Moab Brand Trails although not much of a descent there. There are lots of trails with rock gardens and a little flow between those

Fruita, CO has 18 Road and it is only 70 miles from Moab. Fantastic flow trails there.

 

Near Hurricane is the Zen Trails for fast non-technical flow.

Need to seriously correct this misinformation. Zen is in St. George, not Hurricane, a 30 minute difference. It is also a black diamond technical trail, not designed as a flow or xc trail.

If you want the only flow trails in the area you need to actually go to Hurricane and ride the JEM/Dead Ringer/Cryptobionic system. All of the other trails are moderate XC in nature or higher technical.

Northern Utah has a greater number of intermediate type single track.

 

Yep, JEM is the flow trail system, thanks for catching that. Zen is the trail I'll hit first when I return there in March so was thinking about that.

Actually Zen is a cool intermediate trail if you don't try to ride the few advanced sections and you like rock features. Not many hike-a-bike sections and they are short.

Near St. George there is Barrel Roll. Rather flowy and not a difficult climb.

 

The OP asks a very broad question as Utah is a big state with plenty of great mountain biking. If I was looking for the trails he's after, I'd be heading to Park City as the amount of trail options seems never-ending.

I personally spend more time in SW Utah on the trails being discussed her due to it's proximity to San Diego and would agree that the JEM is flow trail #1 in the area with Barrel Roll also a good option. I'm sure there are others in the area that I don't frequent. I would agree with LeDuke that Zen is a "blue-black" trail and nowhere near a double black.

 

If you want tons of miles on non-technical XC trail, Park City has miles and miles of that (with a few more gnarly techy trails mixed in if you want). You can ride for days between Deer Valley, PCMR, and the Canyons without having to park or drive anywhere. In addition to that, you have numerous other easy trails in Park City (round valley, flying dog, etc). as well as Corner Canyon and Heber options (Coyote Loop, Wasatch Over Wasatch) all within 1 hour drive. Depending on the time of year and what part of the state you are wanting to ride, there are so many options. Southern Utah stuff as discussed above is great (including the supposedly non-techy Zen trail which really does have some technical stuff and require a fair amount of walking for a beginner but is definitely do-able). If you want to ride more alpine stuff, which should be ride-able later spring, early summer, then the Park City option is exceptional. Have a great trip!

 

If you want tons of miles on non-technical XC trail, Park City has miles and miles of that (with a few more gnarly techy trails mixed in if you want). You can ride for days between Deer Valley, PCMR, and the Canyons without having to park or drive anywhere. In addition to that, you have numerous other easy trails in Park City (round valley, flying dog, etc). as well as Corner Canyon and Heber options (Coyote Loop, Wasatch Over Wasatch) all within 1 hour drive. Depending on the time of year and what part of the state you are wanting to ride, there are so many options. Southern Utah stuff as discussed above is great (including the supposedly non-techy Zen trail which really does have some technical stuff and require a fair amount of walking for a beginner but is definitely do-able. The technical sections are not long but there are so many small features that can catch you off guard so beginners will probably be walking more than you think). If you want to ride more alpine stuff, which should be ride-able later spring, early summer, then the Park City option is exceptional. Have a great trip!

 

I love Park City riding.

 

I need to get you to Crested Butte then.

 

Yes, yes you do!

 

Not one mention about Goosberry Mesa

 

Probably because the OP wanted to know about "DH flowing tracks" and Gooseberry doesn't fit that criteria. That doesn't discount the fact that GM is one of the better rides in all of Utah.

 

How does he get back to his car after he has gone down the mountain if he is not looping around?

 

He asked for beginner/intermediate. Of which Gooseberry most definitely is not.

 

I abused my wife on South Rim Trail when she was low intermediate One of her fav trails now, along with Guac.

I haven't rode the trails out Windmill. Maybe something low intermediate out there. Or that new trail by Grafton Mesa? Anyway, the OP wanted flow and the JEM system does that well. Maybe Barrel Roll could be considered kind of flowy. Fast anyway.

If anyone wants serious flow with big berms we built the Demo Flow Trail in the Santa Cruz Mountains. A lot of work to get to the top but 4 miles of big burns and rollers! The recent storms dropped a lot of trees so it will be a while before they, and the narrow mountain roads, are cleared and open.

We have a much smaller version with far less descent at South Lake Tahoe. I would take JEM over that one but we're expanding it. It is lives at the bottom of some amazing trails so in itself it isn't a destination like the Demo Flow Trail.

 

Here's a link to a blog post titled 4 Moab Trails for the Intermediate Rider