Location.--Latitude 46°16'30", Longitude
122°54'48", in SW 1/4 SE 1/4 Section 10, Township 9 North,
Range 2 West, in Cowlitz County, Hydrologic Unit 17080005, on
left bank 40 feet downstream from Arkansas Valley Road bridge in Castle
Rock, 2.7 miles downstream from Toutle River, and at river mile
17.3. Drainage
area is 2,238 mi2. Datum of
gage is NAVD of 1988. For information on previous datum and previous
drainage area, refer to the annual
data report (PDF).