Gauge Description:

A USGS gauge and paddler's gauge both exist at the Hwy.C bridge. A reading of 4.0' on the USGS gauge equates to 0" on the paddler's gauge on Hwy.C bridge. All readings beyond that are direct linear correlation, with conversion from tenths being required.
I.E., (USGS - 4.0') * 12 = Paddler's Gauge.
E.G., If USGS reads 5.15': subtract 4', getting 1.15'. Now multiply by 12 to get 13.8" (or round up to 14") as the Hwy.C bridge gauge reading.

Min(230 cfs, 0") and Max(1130 cfs, 20") are estimates for 'best' runnability.

While the reach can be paddled at levels below 230cfs (4.0' on USGS gauge, or 'zero' on the paddlers gauge) it will be increasingly scrapey. (We are aware of runs down to -4" or so.)
At levels above the 'suggested maximum', the drops on this run will get big and continuous. Experienced boaters will certainly enjoy runs above the listed "maximum", but caution is urged. In truth, the river is runnable at all historic high levels.

Gauge Data (using data from 1998-06-01 through 2008-08-24):

The 10/90 of 3.79 confirms that this river has what would be considered relatively uniform flow (which is why it is runnable most of the year, and will sustain the rafting businesses in the area).

Approximate stage/gauge correlations (subject to periodic adjustment):
4.00 =  0" = 257 cfs
4.25 =  3" = 347 cfs
4.50 =  6" = 460 cfs
4.75 =  9" = 581 cfs
5.00 = 12" = 714 cfs
5.25 = 15" = 861 cfs
5.50 = 18" =1020 cfs
5.75 = 21" =1180 cfs