American, North Fork
3. Colfax-Iowa Hill Road to Yankee Jims Road(Chamberlain Falls)
| Difficulty | IV |
| Length | 4.8 mi |
| Avg Gradient | 41 fpm |
| Gauge | Nf American R a North Fork Dam Ca |
| Flow Rate as of 1 hour | 634 cfslow runnable |
| Reach Info Last Updated | June 8, 2022 |
River Description
The North Fork Chamberlain run is a very popular run due to it's proximity to Sacramento, and great class IV white water. At 4.9 miles, it's a fairly short run, but it is stacked with rapids and flows typically December through June in an average year. If you are looking for fun class IV in the winter and sping, this run is perfect. It only takes a little rain to bring the levels up to a boatable level. 300-400 cfs is the bare-bones minimum, 1000-2500 the sweet spot for most boaters, and above 2500 increasingly pushy and difficult. It has been run as high as 20,000+cfs but this is the territory of big water class V boaters only. Be warned. Although this isn't a super hard class IV stretch, it has it's fair share of undercuts, and pin rocks and was the scene of several bad rafting accidents some years ago when rapids were in a somewhat different configuration than now. Due to the fact that it's run so often, it can be easy to underestimate the dangers. Boaters who use this run to jump from class III to IV, should be sure to go with an experienced group of boaters, and to scout and set up proper safety where needed.
For more information, also check out CA Creeks, and Wet State, Holbeck and Stanley, Cassidy and Calhoun.
Camping is now permited in the following areas on the North Fork American:
· 2000’ downstream of Iowa Hill Bridge to 1000’ upstream of Yankee Jim Bridge
· 2000’ downstream of Ponderosa Bridge to 1 mile downstream of Codfish Creek
A permit is required. These can be picked up at the Auburn State Recreation Area Office.
Contact Auburn State Recreation Area Whitewater Recreation Office: (530) 823-4162
CA State Parks Gold Fields District Office: (916) 988-0205
River Features
Mineral Bar Put In
On upstream river left side of the bridge. Administered by State Parks. Pass required.
Slaughter's Sluice
Chamberlain Falls
Large hole in the center. Most boaters take the tongue on the left.
Tongue and Groove
Follow the tongue on the left.
Zig Zag
Boulder garden
Achilles' Heel
Another boulder garden.
Bogus Thunder
There is a large boulder in the middle of this run that makes the rapid challenging. One can run right down the middle, over a small hole, and down the tongue. You can also cut over to river left and catch a small channel down to the bottom. This rapid changes as the flows rise and fall. Be sure to scout this one.
Grand Slalom
Read and run around large boulders. The rapid takes you far left, then right, then back to the right. At low to med flows, there are eddys that can be caught throughout this rapid.
Staircase
Pick your way through small drops and waves to set up for the exit chute.
Nose Stand
This rapid creates a great traditional spot to go for old school nose stands. It is the scene of many an icecream headache and missed roll in the dead of Winter.
Yankee Jim Bridge
Take out on the beach river left upstream of the bridge
Trip Reports
Log in to add a reportVarious photos from the past season. Just in time for the bridge closure, which went into effect on May 19, 2025.
How low is too low? With an early season atmospheric river pointed towards the north state, a lot of us were playing the speculation game ala CNFRC forecasting. I personally settled on E to P the saturday (main brunt of the flows), and took the sunday on Chambies as a consolation prize. The storm peaked at 1500 on the clementine gauge saturday around 12pm, and quickly dropped out. Our group ran a leisurely lap from 10am to 2pm sunday and had steadily dropping flows.
Turns out this is about the lowest I'd go. Gauge at 0.8 at put in, probably lower. It goes, but it's just really scrapey. Most of our group portaged around the last drop on the left at Bogus.
Wood in Bogus Thunder. See attached photo from below. It is unknown exactly where the wood starts, but it sticks out downstream of the toaster slot.
Low flow Chamberlain lap - put in gauge was below the level to register (estimate 1.0), but the group agreed estimated flow was 600-700 CFS and rising. A bit boney in some areas, and Chamberlain Falls right line was certainly very tight. All of us in hardshells did just fine but needed to be vigilant for rocks in the channel.
Video from March 20, 2021 with approximately 900cfs: https://www.youtube.com/watch?v=Ho9QKJfCfPw
With a staff retreat and board meeting in Sacramento, the American Whitewater crew got out on the North Fork American River with the community.