Boulder Creek, South
02. Pinecliffe to Gross Mountain Reservoir(USB)
| Difficulty | V+ |
| Length | 4.8 mi |
| Avg Gradient | 229 fpm |
| Gauge | South Boulder Creek Above Gross Reservoir at Pinecliffe |
| Flow Rate as of 6 hours | 334 cfslow runnable |
| Reach Info Last Updated | June 6, 2025 |
River Description
*Note there is a new takeout. Details at the end of the description.
The Upper South Boulder Creek is a beautiful section of Colorado Class V that will keep your attention for this section as the chill flat pace of the creek in Pinecliffe is not what awaits you around the corner downstream.
USB has an uncharacteristic section of water at put-in with a concrete channel piping you straight into the first snaking Class V rapid.
Trainspotting Rapid: Entering this drop from the center and snaking your way left to stay off the sharp and blasted rock from the right wall proves about a 30' drop in as many feet downstream. After Trainspotting, you get a brief chance to collect pieces and parts. Collect debris on the center right island.
In the area after Trainspotting, be sure that your crew is in good communication and in tight formation with a plan to catch the eddies on the right after the creek entrance on river right.
The run gets remote quickly after the water runs directly into a wall on river left at the Gash.
( P )\* Portage river right.
While there, please pay respects to a fellow Colorado legendary boater, Paul Zirkelbach whom lost his life here. Keep your group tight and pay attention.
Many people have run the Gash, and it used to be run regularly. There is an underwater sieve that is extremely dangerous and is why it doesn't get run anymore. It's not really worth the risk.
After Gash, there is about a 1/2 mile of continous boogie water before S-Turn. S-turn is a great rapid immediately followed by LZ, which is a portage. Scout your takeout eddy below S-turn and take out on the right to portage LZ.
The remainder of the run has more hair and loads of unique features, good beefy ledges and tight twisting Colorado creekin'. The action really gets going after LZ. Everything is runnable down to the reservoir. There are lots of drops in this section and the last major rapid
...River Features
Put In
Take Out
Trip Reports
Log in to add a reportfan rock on third drop, low water mank
multiple railroad tyes now clogg entrance and landing of the right side sneak - wall angle shows some sieving angles that nobody wants ANYTHING to do with
entrance into the Gash rapid
just above the turn into Trainspotting Rapid
from above
from the hwy 72 bridge looking downstream
rockslide/wind shear caused this mature red fir to go down across the river
The Gash
Looking up the rapid 'trainspotting', a fairly busy starter rapid.
mature fir downed from river right crossing entire creek
See more pictures of Colorado, including a larger-sized copy of this one, at http://www.alexjharvey.com/CO.htm.
this picture shows the lead-in above Trainspotting
'bout half mile in the run, basic slackwater with flake feature