Upper Middle Cosumnes V-V+

The Cosumnes River is a very unique watershed located between the American and Mokelumne drainages. Pronounced "ko-Sue-mees" the river is thought to have been named as the Mokelumne and Tuolumne rivers were, using the -umne suffix meaning "people of" as well as the cos- prefix meaning "salmon or fish".

Old River left Put-in on the UMC.


It is also arguably the only un-dammed river in the Sierra Nevada. Not that any other river isn't dammed, but that the Cosumnes only has minor dams near Rancho Murieta. Perhaps it deserves a "least dammed river of the Sierras designation". It is also one of the smallest watersheds of the Sierra, with an estimated total length of eighty miles.

Because of it's short length and low elevation headwaters, the Cosumnes has a water schedule of it's own, and for many years lacking a gauge, the Upper Middle Fork was rarely run, with downstream reaches seeing more recreational use.

Over the last few years forays by local paddlers, namely missions headed Jared Nocetti, have redefined the UMC. This exploration has been augmented by a new online gauge at Mt Akum, a few miles below take-out. Once given a V+ rating when 800cfs was believed to be the ideal flow, trips have now been made with flows as low as 170cfs. I consider ideal flows to be 300-400, which mellows the run out to nice hard class V run. If desperate I'll go as low as 275 and when looking for something spicy, up to 500. I'd imagine it's everything of V+ at 800cfs. Everything has been run, but I always make at least four portages.

I joined up with Thomas Moore, Taylor Cavin and Ben Wartburg for my first trip down the UMC. The shuttle is short in length, but time consuming due to an unmaintained road and many turns - more details on that later. The run requires a short hike in on what has become a decent trail.

Initially the hike is on a road, then a trail, followed by a short float down a tributary before it cascades into the UMC. Thomas Moore about to start the final leg of the hike.


2010 Update: The hike on river right is only five minutes and the river above the old put-in offers several more good rapids. Stay on your toes for the second one which contains a sticky hole at higher flows.

Scotty enjoys a nice slide above the archaic put-in.


Thirty minutes of hiking is just about perfect to warm up, which is good, because the UMC gets going in good form. Thomas Moore, Ben Wartburg and Darin McQuoid @ 275cfs.


Granite abounds as gradient drops away, and if a group member knows the run there is no need to scout several fun rapids. Stephen Wright on an early slide @ 275cfs.


The first portage comes up quickly, and is very dicey if it's early in the season, the rock stays damp and slick. It was once the largest rapid of the run, but a log moved out of the drop and put the mean pothole on river left in play. Tony Hawk "a friend forever" - Taylor Cavin


Below Tony Hawk a short pool leads to another portage around some mank that has been run at higher flows. This portage requires more friction climbing, and while it doesn't look too bad, Thomas Moore is standing above a small sieve. This one always gets my heart going.


Gradient continues at a steady pace.


The next two move drop has more bark than bite, although it is possible to get stuck in a toilet bowl eddy in the bottom, it's also possible to work you way back out. Ben Wartburg making the first move on the wall @325cfs.


Thomas Moore drops the second tier @ 325cfs.


The same from below, Stephen Wright @ 275cfs.


Next up is an oh so sweet boof formed by a singular rock whose essence is quite hard to capture. Stephen Wright @ 275cfs.


Several steep technical drops link together, keeping the paddler busy until bedrock appears. Looking back upstream, it all goes quite nicely.



It's about to get really good - Taylor Cavin, Ben Wartburg, Thomas Moore.


It's really good. Taylor Cavin enjoying some of the finest on the UMC @ 275cfs.


Thomas Moore enjoys a nice soft landing @ 275cfs.


Thomas Moore and Ben Wartburg below the boof @ 275cfs. This rapid continues around the corner, and you want to be sure to run down the right side and eddy out for a portage.


The portage is one of the reasons to do the UMC with flows below 350, because at high water you either need to run the drop or perform an exposed high route portage. At normal flows you can seal launch in and ferry across the bottom of the drop, landing in the pool above a personal favorite.


Skate Park is a rapid of my preferred flavor: big & intimidating, but with very little consequence, and no two runs are ever the same. The line is marked by a rib of rock that stays visible under several inches of water.

Thomas Moore stays dry in Skate Park @ 325cfs.


It's common to run Skate Park and not get your head wet on the entry move, but occasionally people hit the seam and sub out for twenty feet.

Stephen Wright about to mystery move @ 275cfs.


Ben Wartburg punching the bottom hydraulic @ 275cfs.


Skate Park = Super fun = big smiles = Thomas Moore.


One last look...


Below is another quick portage around a mank pile that has been run, then several fun boulder gardens leading into Lars Holbek's drop. It's worth a quick scout to get a feeling for what the water is doing at the lip.

A delayed boof is ideal because the landing isn't too deep. Taylor Cavin pulls the trigger @ 275cfs.


We were all surprised at how much spicier Lars Holbeks was at 325 cfs. Thomas Moore.


Canyon walls peel away and the gradient tapers off below Lars Holbeks drop.


As Tony Hawk faded into the past, motivated kayakers moved a log to open a previous portage. Ben Wartburg runs "brace for your face" at 325cfs.


Darin McQuoid "brace for your face" @ 275cfs.


One last big rapid marks the end of the steep section of the Upper Middle Consumnes. This drop goes a lot better than it looks, but is friendlier at higher flows than vice versa.

Taylor Cavin runs the transition rapid - 275 cfs.


John McConville from above at 275cfs.


The river character changes completely, the granite is gone and read-n-run boulder gardens fill the river until "V-Slide".

"V-Slide" is a bedrock (but not granite) slide that drops into a large hole, notorious for making anyone stuck in it swim. From what I have heard if she has you, she doesn't let go.

Taylor Cavin looks very focused on the entrance move.


You need to land with your bow to the right as Taylor shows us.


This shot of Taylor Cavin in the eddy shows the boil and backwash of V-Slide.


More fast moving boulder gardens continue until "Blue Angel Slide' a rapid more reminiscent of the Roadside Alseseca than California. At high flows the Blue Angel Slide links right into Cheesegrater, an aptly named slide.

Taylor Cavin gets his grating on.


Once past cheesegrater the river is more fun read and run, with one rapid hiding a notorious undercut rock on the left, where thankfully what goes in comes back out. As take out approaches the gradient continues to slack, and quartz rocks appear like icebergs which in turn make the water glow an iridescent green. This sight would make the run worth doing, let alone the miles of quality rapids.

While the UMC does have a hike in and its fair share of portages, I find it to be a classic where the thought returning brings a smile to my face. I'd consider 275 cfs an ideal first time flow, while 325 makes the top notably more pushy, the run out gets quite splashy and entertaining.

Video of the run with 275cfs.



The shuttle logistics from 50 East:
Take Missouri Flat Exit, right off the off-ramp. Follow for several miles until you T into a left turn on Pleasant Valley Road. Continue until a stop sign and right turn on Bucks Bar Road. Stay on Bucks Bar until another stop sign and right turn on Akum Road, which you stay on passing over the Middle Cosumnes (alternative take out) eventually making a left turn on Fairplay Road. Climb up Fairplay Road until a left turn on Perry Creek road, which you will only spend a few miles on until a right turn onto Slug Gulch Road. Stay on Slug Gulch road until there is a private road sign on the left for Vineyard View road. Don't take Vineyard View, but this unmarked road (Rocky Ridge) on the left. Google Maps Marker for Take-Out.


This unmaintained road leads to the river, when in doubt stay to the right on the most used road, until a gated road comes in from the right. Park here and walk past the gate to the river, the owner is friendly to boaters and you should scout your take out location. Years ago this run required high clearance 4wd, but as of 2010 it's possible in a Subaru provided you leave your boats up top to cut down on weight.

To put in: As of 2010 things have changed, the land owners on river left are not friendly, so a longer shuttle is required to return to river right. Backtrack to the four way stop at Bucks Bar Road. Now turn right onto Grizzly Flat Road and follow until a right turn on Caldor Road. Follow Caldor Road for quite a ways, staying right at the Y. Forest Road 9N60 crosses Caldor road, but the sign on the right is missing, so watch for a sign on the left, but turn right on 9N60. Follow to the gate (open 2010). Park above the gate if you don't want to drive through any brush, and hike an extra five minutes or drive through a little brush to park by Dog Town Creek. Hike across the creek and over the small ridge (maybe five minutes) to the Upper Middle Cosumnes.



There are two optional take out routes: a lower take out so the road could be done without needing high clearance vehicles, but it requires an extra six miles of paddling through what is reported to be a very overgrown riverbed and not worth it.

One can also access the upper take out via river right on Rocky Bar Road, but it's rough 4WD conditions (it will bottom out your standard 4WD pickup) and it takes about as long as just driving around to the better road.