PROVISIONAL DATA SUBJECT TO REVISION

Station operated in cooperation with Portland Water Bureau.

STATION.--14142500 SANDY RIVER BELOW BULL RUN RIVER, NEAR BULL RUN, OR
LOCATION.--Lat 45° 26'57", long 122° 14'38", in SW 1/4 sec.30, T.1 S., R.5 E., Clackamas 
    County, Hydrologic Unit 17080001, on left bank 0.1 mi. downstream from Bull Run River, 
    0.2 mi downstream from Dodge Park, 400 ft below city of Portland water conduit crossing 
    Sandy River, and at mile 18.4. [location map] 
DRAINAGE AREA.--436 mi2. 
PERIOD OF RECORD.--April 1910 to September 1914, October 1929 to September 1966, May 1984 to 
    current year. Monthly discharge only for some periods, published in WSP 1318.  
GAGE.--Water-stage recorder. Elevation of gage is 240 ft. above NGVD of 1929, from 
    topographic map. April 1910 to September 1914, staff gage at present site at different 
    datum. October 1929 to September 1966, water-stage recorder at site 0.8 mi downstream at 
    different datum. 
REMARKS.--Flow regulated since 1915 by Bull Run Lake, since 1929 by Bull Run Reservoir 
    Number One (station 14139000), and since 1961 by Bull Run Reservoir Number Two (station 
    14139900). Some fluctuation caused by Bull Run powerplant of Portland General Electric 
    Company. Portland Water Bureau diverted 178,200 acre-ft from Bull Run River  during the 
    1994 water year, of which 50,500 acre-ft were used for power generation by Portland General     
    Electric Company and returned to Bull Run River. 
EXTREMES FOR PERIOD OF RECORD.--Maximum discharge, 84,400 ft3/s Dec. 22, 1964, gage height, 
    22.3 ft, site and datum then in use; minimum discharge, 45 ft3/s Sept. 26, 1962, minimum 
    daily, 63 ft3/s Oct. 12, Nov. 9, 1952.
EXTREMES FOR FEBRUARY 1996 FLOOD.-- Maximum discharge, 68,600 ft3/s, Feb. 7, gage height, 
    22.59 ft from rating curve extended above 28,000 ft3/s on basis of estimate derived from 
    slope-area measurement; minimum discharge, 199 ft3/s Aug. 23. 

NOTE: The most current shifted rating for this site can be found at USGS Rating Depot website.