USGS Water-Year Summary 2023
01579550 SUSQUEHANNA RIVER NEAR DARLINGTON, MD
LOCATION - Lat 39°37'33.8", long 76°09'27.9" referenced to North American Datum of 1983, Harford County, MD, Hydrologic Unit 02050306,
DRAINAGE AREA - 27,300 mi². from automated delineation using 30-meter National Elevation Dataset digital elevation model data dated 2011.
GAGE - Electronic data logger and water-quality monitor. Datum of gage is 9 ft above North
American Vertical Datum of 1988.
COOPERATION - Funding for continuous water-quality data collection is provided by the U.S. Geological Survey.
PERIOD OF RECORD - WATER TEMPERATURE: Feb 2014 to current year.
SPECIFIC CONDUCTANCE: Feb 2014 to current year.
DISSOLVED OXYGEN: Feb 2014 to Sept 30, 2015.
pH: Feb 2014 to Sept 30, 2015.
TURBIDITY: Feb 2014 to current year.
NITRATE: Aug. 2014 to current year.
INSTRUMENTATION - Deployed multi-parameter monitor meter was equipped with integrated temperature and specific conductance sensor, pH sensor, turbidity, dissolved oxygen optical sensors. Also deployed, is a Nitrate monitor meter with internal temperature sensor. Monitor meters are connected to an electronic data logger (EDL). Data was collected on fixed 15 minute intervals (0 and 15 minute marks) and transmitted every 1 hour via modem.
EXTREMES FOR PERIOD OF DAILY RECORD
WATER TEMPERATURE: Maximum, 34.9°C, July 23, 2016; minimum, -1.0°C, on Feb 14, 2014.
SPECIFIC CONDUCTANCE: Maximum, 415 microsiemens per centimeter, March 7, 2015; minimum, 114 microsiemens per centimeter, multiple occurrences, first occurrence on August 15, 2018.
pH: Maximum, 12.6 standard units, May 20, 2013; minimum, 6.6 standard units, Sept. 4, 2014.
DISSOLVED OXYGEN: Maximum, 18.6 milligrams per liter, March 3, 2014; minimum, 5.7 milligrams per liter, July 28, 2014.
TURBIDITY: Maximum, 269 formazin nephelometric units (FNU), November 05, 2019 ; minimum, 0.0 formazin nephelometric units (FNU) Oct. 2, 2015.
NITRATE: Maximum, 2.21 milligrams per liter on January 25, 2019; minimum, 0.38 milligrams per liter, on many days. First occurrence was September 15, 2016.
NITRATE (Temporary Right Bank Location): Maximum, 1.26 milligrams per liter, on many days. First occurrence was November 22, 2019; minimum, 0.86 milligrams per liter, on many days. First occurrence was October 30, 2019.