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Water-Year Summary for Site 14220500

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  • Water-Year Summary reports summarize a year of hydrologic data in a printer-friendly format.
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Available Parameters
00060 Discharge(Mean)  
00065 Gage height(Mean)  

Water year 2023: 2023-10-01 to 2024-09-30

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USGS Water-Year Summary 2023
LOCATION - Lat 45°57'07", long 122°33'46" referenced to North American Datum of 1927, in NW 1/4 NE 1/4 sec.04, T.5 N., R.2 E., Cowlitz County, WA, Hydrologic Unit 17080002, on right bank 0.4 mi southeast of Ariel, 0.5 mi downstream from Merwin Dam and powerplant, 3.3 mi upstream from Cedar Creek, and at mile 19.0.
DRAINAGE AREA - 731 mi².
REVISIONS HISTORY - WSP 884: 1938. WSP 984: 1936-37, 1940-42. WSP 1318: 1924-30(M).
PERIOD OF RECORD - July to October 1909, November 1909 (gage heights only), July to October 1922, July 1923 to current year. Published as "near Ariel" water years 1922-29. Prior to October 1952, discharge measurements made at site 0.5 mi downstream; low discharges not equivalent due to local inflow.
GAGE - Water-stage recorder. Datum of gage is 44.0 ft above NGVD of 1929 (levels by Pacificorp). July to November 1909, nonrecording gage at site 4 mi upstream at different datum. July 27 to Oct. 29, 1922, and July 31, 1923, to Apr. 20, 1930, nonrecording gages at site 0.5 mi downstream at datums 3.90 ft and 0.90 ft higher respectively, than present datum.
REMARKS - No diversion upstream from station. Flow regulated by Swift and Yale Reservoirs, and Lake Merwin (stations 14217600, 14218500, 14220000). New capacity tables for these reservoirs were put into effect on October 1, 2008. Chemical analyses July 1959 to June 1960, April 1979 to September 1986. Additional data from April to August 1980 are published in U.S. Geological Survey Open-File Report 81-1007. Water temperatures October 1950 to September 1963. U.S. Geological Survey satellite telemeter at station.
EXTREMES FOR PERIOD OF RECORD - Maximum discharge, 129,000 ft³/s, Dec. 22, 1933, gage height, 35.0 ft, from floodmarks, from rating curve extended above 56,000 ft³/s on basis of computation of peak flow over dam; no flow at times June 30, July 1-3, 6-9, 1931 (caused by regulation during construction of Merwin Dam); minimum daily discharge, 1 ft³/s, July 6, 1931.