PROVISIONAL DATA SUBJECT TO REVISION

Station operated in cooperation with Portland General Electric.

STATION.-- 14137000  SANDY RIVER NEAR MARMOT, OR
LOCATION.--Prior to October 1, 2002 located at Lat 45° 23'55", long 122° 07'33", 
in NW 1/4 sec.18, T.2 S., R.6 E.,Clackamas County, Hydrologic Unit 17080001, on right 
bank  0.6 mi west/northwest of Marmot, 0.3 mi upstream from  Marmot Dam of Portland 
General Electric Co., 7.2 mi downstream from Salmon River, and at mile 30.3.[location map] 
DRAINAGE AREA.--263 mi2.
PERIOD OF RECORD.--August 1911 to current year. Monthly discharges only, January 
to September 1916, October 1918 to June 1919, published in WSP 1318.  Published as "at 
Marmot" October 1912 to September 1913.  Records for January 1916 to June 1919, 
published as "below dam, near Marmot," obtained by combining records for Sandy River 
below dam, near Marmot, with records for Sandy River Canal near Marmot. Discharges 
from September 30, 2002 to Oct. 18, 2008 are the combined flows of 14137001 and 14137002.
GAGE.--Prior to October 1, 2002 water-stage recorder. Datum of gage is NGVD of 1929 
(levels by PGE). Aug. 15, 1911, to Dec. 20, 1915, and July 2, 1919, to Oct. 19, 1933, 
nonrecording gage at site 1.5 mi upstream at different datum. Oct. 20, 1933, to 
Sept. 30, 1958, water-stage recorder at site 1.1 mi upstream at different datum.  
Sept. 30, 1958 to Mar. 11, 1997, water-stage recorder at site 0.6 mi upstream, at 
different datum.
REMARKS.--No  regulation or diversion upstream from station.
EXTREMES FOR PERIOD OF RECORD.--Maximum discharge, 61,400 ft3/s Dec. 22, 1964, gage 
height, 17.05 ft, site and datum then in use, from rating curve extended above 7,000 ft3/s; 
maximum gage height, 20.40 ft, Feb. 7, 1996, site and datum then in use; minimum, 
190 ft3/s Oct. 13, 1994.

NOTE: River forecasts and additional data can be obtained at the National Weather Service's Advanced Hydrologic Prediction Services web page.