USGS Water-Year Summary 2019
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 unit is a YSI-EXO multi-parameter monitor meter equipped with YSI-6580 integrated temperature and specific conductance sensor, YSI-6561 pH sensor, YSI-6136 turbidity, and YSI-ROX-6150 dissolved oxygen optical sensors. Also deployed, is a SUNA Nitrate monitor meter with internal temperature sensor. Monitor meters are connected to a Campbell Scientific CR1000K data logger (EDL). Data was collected on fixed 15 minute intervals (0 and 15 minute marks) and transmitted every 1 hour via a Sierra Wireless AirLink Raven modem.
EXTREMES FOR PERIOD OF DAILY RECORD - WATER TEMPERATURE: Maximum, 32.5°C, August 14, 2015; minimum, -1.0°C, on Feb 14, 2014.
SPECIFIC CONDUCTANCE: Maximum, 415 microsiemens per centimeter, March 7, 2015; minimum, 131 microsiemens per centimeter, March 14, 2015.
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, 120 formazin nephelometric units (FNU), April 30, 2014; minimum, 0.6 formazin nephelometric units (FNU) 8/13,14,17,25, 2015
NITRATE: Maximum, 1.84 milligrams per liter, March 7, 9 and 11, 2015; minimum, 0.55 milligrams per liter, May 23, 2015.