USGS Water-Year Summary 2024
07374000 Mississippi River at Baton Rouge, LA
LOCATION - Lat 30°26'44.4", long 91°11'29.6" referenced to North American Datum of 1983, in sec.45, T.7 S., R.1 W., West Baton Rouge Parish, LA, Hydrologic Unit 08070100, located on a city Pier, approximately 1.5 mi upstream of the Port Allen Locks, between the I-10 and Hwy. 190 bridges over the river.
DRAINAGE AREA - 1125810 mi².
SURFACE-WATER RECORDS
PERIOD OF RECORD - March 2004 to current year. Miscellaneous measurements made at site prior to 1976.
GAGE - Water-stage recorder and water-quality monitor. Datum of gage is NAVD 88.
Records in the USGS database prior to 2004 were taken from US Army Corps of Engineers publications and adjusted to MSL based on datum information available in those publications.
EXTREMES FOR PERIOD OF RECORD - Maximum discharge, 1,436,000 ft³/s, May 18-19, 2011; maximum gage height, 45.48 ft, May 18-19, 2011; minimum recorded discharge, 132,800 ft³/s, Oct. 31, 2012; minimum recorded gage height, 3.43 ft, Oct. 31, 2012.
WATER-QUALITY RECORDS
PERIOD OF RECORD - Water years 1975-76, 1988, 1991-current year.
PERIOD OF DAILY RECORD - SPECIFIC CONDUCTANCE: October 2004 to current year.
WATER TEMPERATURE: October 2004 to current year.
PH: October 2004 to current year.
DISSOLVED OXYGEN: October 2004 to current year.
TURBIDITY: October 2011 to current year.
NITRATE: November 2011 to current year.
INSTRUMENTATION - Water-quality monitor recording temperature, specific conductance, pH, dissolved oxygen, and turbidity. A second monitor is recording nitrate.
EXTREMES FOR PERIOD OF RECORD - SPECIFIC CONDUCTANCE: Maximum, 634 microsiemens/cm, Aug. 23, 2018; minimum, 182 microsiemens/cm, Jun. 4, 2021. WATER TEMPERATURE: Maximum, 32.7°C, Aug. 03, 2012; minimum, 2.2°C, Feb. 21, 22, 2021. PH: Maximum, 8.6 std. units, Mar. 14, 15, 2009; minimum, 6.9 std. units, Mar. 19-20, 2018. DISSOLVED OXYGEN: Maximum, 13.4 mg/L, Feb. 14, 15, 16, 2011; minimum, 5.0 mg/L, Sept. 20, 2018. TURBIDITY: Maximum, 1030 FNU, Apr. 26, 2011; Minimum, 3.8 FNU, Jul. 7, 2012. NITRATE: Maximum, 3.10 mg/L, Jul. 25, 2014; Minimum, 0.22 mg/L, Sept. 11, 12, 13, 2012.