USGS Water-Year Summary 2024
09380000 COLORADO RIVER AT LEES FERRY, AZ
LOCATION - Lat 36°51'51.60", long 111°35'16.34" referenced to North American Datum of 1983, Coconino County, AZ, Hydrologic Unit 14070006, on left bank at head of Marble Gorge at Lees Ferry, immediately above mouth of the Paria River, 28 miles downstream from the Utah state line, 16 miles downstream from Glen Canyon Dam, 61.5 miles upstream from the mouth of Little Colorado River, 87.4 miles upstream from gage near Grand Canyon, and 355 miles upstream from Hoover Dam. By road, it is 7 miles northeast of Marble Canyon and 130 miles north of Flagstaff.
DRAINAGE AREA - 111,800 mi². approximately, including 3,959 mi² in Great Divide Basin in southern Wyoming which is non-contributing (previously considered part of the Missouri River basin).
REVISIONS HISTORY - WSP 859: 1921-23. WSP 1313: 1914-21.
The maximum discharge and date of the peak for water year 1884 were revised on May 30, 2024. The original USGS estimate was incorrectly revised to 300,000 ft3/s in 1938. This revision is rescinded as of May 30, 2024. The month and day of the event were also removed, as there are contradicting reports and no clear evidence for a specific date.
The maximum discharge for water year 1921 was revised on May 30, 2024. The original USGS estimate was incorrectly revised to 220,000 ft3/s in 1938. This revision is rescinded as of May 30, 2024.
See USGS Professional Paper 1677 for additional information about the 1884 and 1921 water year peaks.
SURFACE-WATER RECORDS
PERIOD OF RECORD - Jan. 1895 to current year. Estimates of monthly and annual discharge only for some periods, published in WSP 1313.
GAGE - Water-stage recorder. Datum of gage is 3109.13 ft above NAVD of 1988
Prior to Jan. 19, 1923, nonrecording gages or reference points within 400 ft of present gage, at different datums.
EXTREMES OUTSIDE PERIOD OF RECORD - Maximum discharge since at least 1868, about 300,000 ft³/s July 7, 1884, gage height, 31.5 ft, present site and datum, from floodmark at mouth of Paria River, from rating curve extended above 120,000 ft³/s on basis of discharge computed for flood of June 18, 1921, for station near Grand Canyon.
EXTREMES FOR PERIOD OF RECORD - 1895-1962: Maximum discharge, 220,000 ft³/s, June 18, 1921, gage height, 26.5 ft, from floodmarks, from rating curve extended above 120,000 ft³/s on basis of discharge computed for station near Grand Canyon; minimum, 750 ft³/s, Dec. 27, 1924.
1963-Curent year: Maximum discharge, 97,300 ft³/s, June 29, 1983, gage height, 18.14 ft; minimum daily, 700 ft³/s, Jan. 23, 24, 1963, result of closing coffer dam at Glen Canyon Dam.
AVERAGE DISCHARGE FOR PERIOD OF RECORD - 51 years (water years 1912-62), 17,850 ft³/s, 12,930,000 acre-ft/yr.
WATER-QUALITY RECORDS
PERIOD OF RECORD - Jan. to July 1926, Oct. 1926 to June 1927, Aug. 1928 to Dec. 1933, Nov. 1942 to Oct. 1945, Oct. 1947 to current year.
PERIOD OF DAILY RECORD - SPECIFIC CONDUCTANCE:Oct. 1964 to Sept. 1981, Feb. 1982 to Dec. 1987, Oct. 1989 to Mar. 2003., Feb. 2004 to current year.
pH:Aug. 1990 to Apr. 1993.
WATER TEMPERATURE:July 1949 to Sept. 1981, Feb. 1982 to Dec. 1987, Oct. 1989 to Mar. 2003, Feb. 2004 to current year.
DISSOLVED OXYGEN:Aug. 1990 to Apr. 1993.
SUSPENDED-SEDIMENT DISCHARGE:Oct. 1928 to Dec. 1933, Nov. 1942 to Sept. 1944, Oct. 1947 to Sept. 1965.
TURBIDITY:Oct. 1998 to Sept. 2000, minimum daily values.
INSTRUMENTATION - Specific conductance and water temperature recorder Mar. 1977 to Sept. 1981, Feb. 1982 to Dec. 1987, and Oct. 1990 to current; dissolved-oxygen recorder Aug. 1990 to Apr. 1993.
EXTREMES FOR PERIOD OF RECORD - SPECIFIC CONDUCTANCE: (Aug. 1965 to Sept. 1981, Feb. 1982 to Dec. 1987, Oct. 1990 to current year).
-Maximum, 1,260 microsiemens, Apr. 20,21, 1967; 460 microsiemens, Aug. 10, 1965.
pH:
-Maximum, 8.3, on many days in Jan. to Apr. and June 1991;
-Minimum, 7.6, on several days in Nov. and Dec. 1990, and Mar. 1991.
WATER TEMPERATURE: (Aug. 1965 to Sept. 1981, Feb. 1982 to Dec. 1987, Oct. 1990 to current year).
-Maximum, 21.0 C on several days during Aug., 1967, 1968;
-Minimum, 2.0 C on Jan. 29, 30, 1970.
DISSOLVED OXYGEN:
-Maximum recorded, 11.2 mg/L, Apr. 29, 1991;
-Minimum recorded, 6.4 mg/L, Sept. 18, 1991.
TURBIDITY:
-Minimum daily, less than 1.0 NTU on most days.