Less than a mile up Kannah Creek... like probably 1/2 mile. When running, it's very continuous and hard to stop above the barb wire immediately below the trailhead. It's totally worth exploring if you live in the town of Whitewater, CO. Otherwise, you might save your gas money.
If it weren't for about 100 barb wire fences between the trailhead and the Gunnison River, then the rest of Kannah Creek might be a good run three weeks a year.
I've paddled from Buzzard and all the way down Plateau Creek. Lot of barb wire that keeps the upper Plateau Creek section from being one of the better class II+/III- runs in the area.