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USGS 01578310 SUSQUEHANNA RIVER AT CONOWINGO, MD

PROVISIONAL DATA SUBJECT TO REVISION

Click to hidestation-specific text

For information about dam operations, call 1-888-457-4076 or contact Constellation Energy (http://www.constellationenergy.com/)

LOCATION.-- Lat 39°39'28.4", long 76°10'28.0", Harford County, MD, Hydrologic Unit 02050306, 
   1.0 mi southwest of Conowingo, and 9.9 mi upstream from mouth.
DRAINAGE AREA.--27,100 mi2
PERIOD OF RECORD.--October 1967 to current year.
GAGE.--Water-stage recorder.  Datum of gage is 4.16 ft above North American Vertical Datum of 1988.
REMARKS.--Flow regulated by Conowingo Reservoir beginning October 1928, usable capacity, 55,070,000,000 gal;
   dead storage, 45,290,000,000 gal. Records do not include a small infrequent diversion upstream from station to
   augment municipal supply of city of Baltimore. Records of diversion available from Baltimore City Department
   of Public Works. U.S. Geological Survey satellite data-collection platform at station.
EXTREMES FOR PERIOD OF RECORD.--Maximum discharge, 1,130,000 ft3/s, June 24, 1972,
   gage height, 36.83 ft; minimum discharge, 144 ft3/s, Mar. 2, 1969.
COOPERATION.--Funding for the operation of this station is provided by Constellation Energy Generation.
   Access to gage site provided by Constellation Energy Generation.
Boating safety tips
This station managed by the MD-DE-DC Water Science Center Baltimore office.

Available Parameters Available Period
  
1988-02-02  2025-10-12
2007-10-01  2025-10-12
2025-06-14  2025-10-12







 (7)
 

  -- or --

 


 

Summary of all available data for this site
Instantaneous-data availability statement


Discharge, cubic feet per second

Most recent instantaneous value: 11000 10-12-2025   20:35 EDT
Graph of  Discharge, cubic feet per second

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Daily discharge, cubic feet per second -- statistics for Oct 12 based on 58 water years of record more
Min
(1970)
25th
percen-
tile
Most Recent
Instantaneous
Value Oct 12
Median Mean 75th
percen-
tile
Max
(1977)
540 6980 11000 12400 21200 22400 190000


Gage height, feet

Most recent instantaneous value: 10.52 10-12-2025   20:35 EDT
Graph of  Gage height, feet

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Stream water level elevation above NAVD 1988, in feet

Most recent instantaneous value: 14.65 10-12-2025   20:35 EDT
Graph of  Stream water level elevation above NAVD 1988, in feet

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