USGS Water-Year Summary 2024
09315000 GREEN RIVER AT GREEN RIVER, UT
LOCATION - Lat 38°59'10", long 110°09'02" referenced to North American Datum of 1927, in NW 1/4 NW 1/4 SW 1/4 sec.15, T.21 S., R.16 E., Emery County, UT, Hydrologic Unit 14060008, on right bank 1,400 ft. upstream from a railroad bridge, 0.9 mi. southeast of town of Green River, UT, 22.7 mi. upstream from the San Rafael River, and at mile 117.6 upstream from mouth.
DRAINAGE AREA - 44,850 mi². of which about 4,260 mi² is noncontributing, including 3,959 mi² in Great Divide Basin in southern Wyoming.
REVISIONS HISTORY -
WSP 918: 1895-1899. WDR UT-76-1: Drainage area.
Revisions: Staff gage readings and discharge measurement gage heights for the period Feb. 10, 2022, to Mar 24, 2022, were revised on Nov. 15, 2022, based on changes to the gage datum.
SURFACE-WATER RECORDS
PERIOD OF RECORD - October 1894 to October 1899, March 1905 to current year. Published as "at Blake" 1894-99, as "near Elgin" 1911, and as "at Little Valley, near Green River" 1910-23.
GAGE - Water-stage recorder and crest-stage gage. Elevation of the base gage datum is 4,043.61 ft above NAVD of 1988 from a Level III GNSS survey on June 30, 2022. Prior to November 6, 1914, staff, wire-weight, or chain gages at several sites within 7 mi of present site at various datums. November 6, 1914 to June 20, 1924, water-stage recorder at site 7 mi downstream at different datum. June 21 to September 18, 1924, chain gage, and September 19, 1924 to May 7, 1947, water-stage recorder at site 100 ft downstream at present datum. May 8, 1947 to September 7, 1994, water-stage recorder at site 900 ft downstream at present datum.
EXTREMES FOR PERIOD OF RECORD - Maximum discharge, 68,100 ft³/s, Jun 27, 1917, gage height, 14.53 ft, site and datum then in use; minimum, 255 ft³/s, Nov 26, 1931; minimum gage height, 4.08 ft, Aug 1, Dec 5, 1934.
CLIMATOLOGICAL RECORDS
PERIOD OF RECORD - Precipitation from tipping bucket rain gage from Jun 22, 2021 to present. Air temperature, relative humidity, barometric pressure, wind speed, and wind direction from a multi-parameter weather station from Jun 22, 2021 to present.
EXTREMES FOR PERIOD OF RECORD - Maximum daily precipitation, 0.67 in, Sep 01, 2021.
WATER-QUALITY RECORDS
PERIOD OF RECORD - August 1928 to March 2021 water temperature and specific conductance was measured as daily instantaneous values by an observer. 15-minute water quality data as follows: WATER TEMPERATURE; Mar 10, 2021 to present. SPECIFIC CONDUCTANCE; Mar 10, 2021 to present. DISSOLVED OXYGEN; Jun 22, 2021 to present. pH; Jun 22, 2021 to present; TURBIDITY; Jun 22, 2021 to present.
PERIOD OF DAILY RECORD - WATER TEMPERATURE: May 1949 to September 1959, October 1964 to September 1981, March 1982 to March 2021.
SPECIFIC CONDUCTANCE: October 1941 to September 1981, March 1982 to March 2021.
SUSPENDED-SEDIMENT DISCHARGE: May 1930 to September 1984.
INSTRUMENTATION - Water-quality monitor April 1985 to September 1989. Observer read water temperature until Mar 31, 2021. Observer collected dip samples for lab specific conductance analysis until Mar 31, 2021. A continuous monitor (15-minute readings) with water temperature and specific conductance was installed on Mar 10, 2021. On 2021-06-22 pH, DO, and Turbidity were added to the continuous monitor.
EXTREMES FOR PERIOD OF RECORD - WATER TEMPERATURE: Maximum observed, 30.0°C, Aug 13, 1958, Jul 5, 6, 8, 12, Aug 5, 2001, Jul 9, 14, 2002, Jul 21, 2003, Jul 22, 2007, Jul 4, 2015, several days during Jul 2018, Aug 2 and Aug 4, 2020; minimum observed, -0.2'C on multiple days.
SPECIFIC CONDUCTANCE: Maximum observed, 3,250 microsiemens/cm, Dec 1, 1967; minimum observed, 240 microsiemens/cm, Jun 3, 2014.
SEDIMENT CONCENTRATIONS: Maximum daily mean, 66,000 mg/L, Jul 11, 1936; minimum daily, 19 mg/L, Sep 30, 1974.
SEDIMENT LOADS: Maximum daily, 2,230,000 tons, Jul 11, 1936; minimum daily, 54 tons, Sep 27, 1956. TURBIDITY: maximum instantaneous >4000 FNU on many days. Minimum Instantaneous, 6.3 FNU, Jan 10, 2022. pH: Maximum instantaneous, 8.8 Oct 14, 2022 and Jul 20, 2023. Minimum instantaneous, 7.6 Aug 2, 2021. DISSOLVED OXYGEN: Maximum instantaneous, 14.4 mg/L, Jan 26, 2023; Minimum instantaneous, 4.0 mg/L Jul 26, 2021.