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. (American Whitewater)
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