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Susquehanna River at Conowingo Dam

Highest listed crest 36.83 ftFlood stage 23.5 ft47 crests since 1968

The Susquehanna River at Conowingo Dam crested at major flood stage 5 times among the 47 crests the National Weather Service lists from 1968 to 2021. The highest, 36.83 ft on June 24, 1972, was major flooding, 13.33 feet above flood stage. 11 other gauges on the Susquehanna River crested above flood stage within a week of it, 5 at their own highest listed crest.

The gauge

Highest listed crest
36.83 ft
June 24, 1972; 1,130,000 cubic feet per second
Flood stage
23.5 ft
Major flooding from 28.5 ft
Crests at major
5
16th of 108 gauges in Maryland
Most recent flood crest
September 3, 2021
24.29 ft, minor flooding
Location
Harford County
Near Havre de Grace (8.3 mi), Aberdeen (9.8 mi), Bel Air (12.5 mi)

Flood stages

The thresholds the National Weather Service uses for this gauge today, and how many listed crests reached each.

Flood categories, Susquehanna River at Conowingo Dam
Action stage21.521May 2, 2020The level at which the NWS or its partners begin to take action
Flood stage (minor)23.57Sep 3, 2021Minimal or no property damage, but possibly some public threat
Moderate flood stage24.814Jul 26, 2018Some inundation of structures and roads near the stream
Major flood stage28.55Sep 9, 2011Extensive inundation of structures and roads

Every listed crest

47 crests from 1968 to 2021. Filled: at or above flood stage. Hover a crest for its date and stage.

Listed crests at the Susquehanna River at Conowingo Dam, 1968 to 2021 2025303540ft Flood stage 23.5 ftMajor 28.5 ft Mar 25, 1968: 22.46 ft, action stage; 238,000 cubic feet per secondFeb 4, 1970: 26.40 ft, moderate flooding; 434,000 cubic feet per secondFeb 22, 1971: 22.58 ft, action stage; 243,000 cubic feet per secondJun 24, 1972: 36.83 ft, major flooding; 1,130,000 cubic feet per secondDec 9, 1972: 22.74 ft, action stage; 250,000 cubic feet per secondApr 5, 1974: 22.35 ft, action stage; 235,000 cubic feet per secondSep 27, 1975: 30.92 ft, major flooding; 710,000 cubic feet per secondJan 28, 1976: 24.65 ft, minor flooding; 338,000 cubic feet per secondOct 10, 1976: 23.99 ft, minor flooding; 306,000 cubic feet per secondJan 28, 1978: 25.64 ft, moderate flooding; 377,000 cubic feet per secondMar 7, 1979: 28.04 ft, moderate flooding; 499,000 cubic feet per secondMar 23, 1980: 22.45 ft, action stage; 240,000 cubic feet per secondFeb 25, 1981: 25.18 ft, moderate flooding; 355,000 cubic feet per secondFeb 5, 1982: 23.02 ft, action stage; 261,000 cubic feet per secondApr 17, 1983: 23.31 ft, action stage; 273,000 cubic feet per secondFeb 16, 1984: 28.08 ft, moderate flooding; 501,000 cubic feet per secondMar 16, 1986: 26.17 ft, moderate flooding; 403,000 cubic feet per secondApr 7, 1987: 23.13 ft, action stage; 266,000 cubic feet per secondFeb 4, 1988: 21.64 ft, action stage; 211,000 cubic feet per secondMay 18, 1989: 23.48 ft, action stage; 280,000 cubic feet per secondOct 26, 1990: 23.03 ft, action stage; 262,000 cubic feet per secondApr 2, 1993: 28.06 ft, moderate flooding; 500,000 cubic feet per secondMar 23, 1994: 26.16 ft, moderate flooding; 403,000 cubic feet per secondJan 22, 1995: 21.74 ft, action stage; 214,000 cubic feet per secondJan 20, 1996: 34.18 ft, major flooding; 909,000 cubic feet per secondNov 11, 1996: 24.04 ft, minor flooding; 303,000 cubic feet per secondJan 10, 1998: 25.55 ft, moderate flooding; 372,000 cubic feet per secondJan 26, 1999: 22.90 ft, action stage; 257,000 cubic feet per secondFeb 29, 2000: 22.12 ft, action stage; 228,000 cubic feet per secondMay 15, 2002: 21.62 ft, action stage; 224,000 cubic feet per secondMar 22, 2003: 24.15 ft, minor flooding; 308,000 cubic feet per secondJan 16, 2004: 23.88 ft, minor floodingSep 19, 2004: 30.07 ft, major flooding; 620,000 cubic feet per secondApr 4, 2005: 26.70 ft, moderate flooding; 430,000 cubic feet per secondJun 29, 2006: 27.31 ft, moderate flooding; 461,000 cubic feet per secondMar 17, 2007: 23.04 ft, action stage; 273,000 cubic feet per secondMar 6, 2008: 25.64 ft, moderate flooding; 379,000 cubic feet per secondJan 27, 2010: 24.37 ft, minor flooding; 325,000 cubic feet per secondMar 11, 2011: 21.52 ft, action stage; 220,600 cubic feet per secondApr 19, 2011: 23.46 ft, action stageApr 29, 2011: 25.12 ft, moderate floodingSep 9, 2011: 32.41 ft, major flooding; 777,700 cubic feet per secondFeb 2, 2013: 21.60 ft, action stage; 223,000 cubic feet per secondJul 26, 2018: 26.08 ft, moderate flooding; 401,866 cubic feet per secondNov 28, 2018: 21.52 ft, action stage; 225,000 cubic feet per secondMay 2, 2020: 22.32 ft, action stage; 252,000 cubic feet per secondSep 3, 2021: 24.29 ft, minor flooding; 326,000 cubic feet per second Highest, 36.83 ft, Jun 24, 1972 197019801990200020102020

Crests at or above flood stage, by decade

Crests at or above flood stage per decade, Susquehanna River at Conowingo Dam 1960s: 0 1970s: 7 7 1980s: 3 1990s: 5 2000s: 6 2010s: 4 2020s: 1 1960s1970s1980s1990s2000s2010s2020s
  1. These are the crests the local National Weather Service office lists for the gauge: the highest on record and recent crests. Lesser floods between them may be missing, so counts by decade are a floor.
  2. Categories use today's flood stages. Levees, dams and channel changes since a crest can make old and new stages not directly comparable.

Highest crests

Highest listed crests, Susquehanna River at Conowingo Dam
1Jun 24, 197236.83+13.33Major1,130,000
2Jan 20, 199634.18+10.68Major909,000
3Sep 9, 201132.41+8.91Major777,700
4Sep 27, 197530.92+7.42Major710,000
5Sep 19, 200430.07+6.57Major620,000
6Feb 16, 198428.08+4.58Moderate501,000
7Apr 2, 199328.06+4.56Moderate500,000
8Mar 7, 197928.04+4.54Moderate499,000
9Jun 29, 200627.31+3.81Moderate461,000
10Apr 4, 200526.70+3.20Moderate430,000
11Feb 4, 197026.40+2.90Moderate434,000
12Mar 16, 198626.17+2.67Moderate403,000
13Mar 23, 199426.16+2.66Moderate403,000
14Jul 26, 201826.08+2.58Moderate401,866
15Jan 28, 197825.64+2.14Moderate377,000
16Mar 6, 200825.64+2.14Moderate379,000
17Jan 10, 199825.55+2.05Moderate372,000
18Feb 25, 198125.18+1.68Moderate355,000
19Apr 29, 201125.12+1.62Moderate—
20Jan 28, 197624.65+1.15Minor338,000
21Jan 27, 201024.37+0.87Minor325,000
22Sep 3, 202124.29+0.79Minor326,000
23Mar 22, 200324.15+0.65Minor308,000
24Nov 11, 199624.04+0.54Minor303,000
25Oct 10, 197623.99+0.49Minor306,000
26Jan 16, 200423.88+0.38Minor—
27May 18, 198923.48−0.02Action280,000
28Apr 19, 201123.46−0.04Action—
29Apr 17, 198323.31−0.19Action273,000
30Apr 7, 198723.13−0.37Action266,000
31Mar 17, 200723.04−0.46Action273,000
32Oct 26, 199023.03−0.47Action262,000
33Feb 5, 198223.02−0.48Action261,000
34Jan 26, 199922.90−0.60Action257,000
35Dec 9, 197222.74−0.76Action250,000
36Feb 22, 197122.58−0.92Action243,000
37Mar 25, 196822.46−1.04Action238,000
38Mar 23, 198022.45−1.05Action240,000
39Apr 5, 197422.35−1.15Action235,000
40May 2, 202022.32−1.18Action252,000
41Feb 29, 200022.12−1.38Action228,000
42Jan 22, 199521.74−1.76Action214,000
43Feb 4, 198821.64−1.86Action211,000
44May 15, 200221.62−1.88Action224,000
45Feb 2, 201321.60−1.90Action223,000
46Mar 11, 201121.52−1.98Action220,600
47Nov 28, 201821.52−1.98Action225,000

The worst floods along the Susquehanna River

For this gauge's highest crests, the other gauges on the Susquehanna River that crested above flood stage within a week.

June 24, 1972: 36.83 ft here, major flooding

  • MariettaPA · Jun 23, 1972 · 64.54 ft · Major · its highest
  • MeshoppenPA · Jun 23, 1972 · 43.51 ft · Major
  • Wilkes BarrePA · Jun 24, 1972 · 40.91 ft · Major
  • SunburyPA · Jun 24, 1972 · 35.80 ft · Major · its highest
  • TowandaPA · Jun 24, 1972 · 33.43 ft · Major · its highest
  • HarrisburgPA · Jun 24, 1972 · 33.27 ft · Major · its highest
  • DanvillePA · Jun 24, 1972 · 32.32 ft · Major · its highest
  • BloomsburgPA · Jun 25, 1972 · 31.20 ft · Major
  • WaverlyPA · Jun 23, 1972 · 21.24 ft · Major
  • VestalNY · Jun 23, 1972 · 22.35 ft · Moderate

January 20, 1996: 34.18 ft here, major flooding

  • MariettaPA · Jan 21, 1996 · 56.80 ft · Major
  • Wilkes BarrePA · Jan 20, 1996 · 34.45 ft · Major
  • VestalNY · Jan 20, 1996 · 27.86 ft · Major
  • HarrisburgPA · Jan 20, 1996 · 25.08 ft · Major
  • WindsorNY · Jan 20, 1996 · 21.22 ft · Major
  • WaverlyPA · Jan 20, 1996 · 20.35 ft · Major
  • BinghamtonNY · Jan 21, 1996 · 18.35 ft · Major
  • MeshoppenPA · Jan 20, 1996 · 36.34 ft · Moderate
  • OwegoNY · Jan 20, 1996 · 32.97 ft · Moderate
  • SunburyPA · Jan 20, 1996 · 30.32 ft · Moderate

September 9, 2011: 32.41 ft here, major flooding

  • SidneyNY · Sep 9, 2011 · 987.36 ft · Major
  • MariettaPA · Sep 9, 2011 · 58.16 ft · Major
  • MeshoppenPA · Sep 8, 2011 · 44.48 ft · Major · its highest
  • Wilkes BarrePA · Sep 9, 2011 · 42.66 ft · Major · its highest
  • OwegoNY · Sep 8, 2011 · 39.62 ft · Major · its highest
  • VestalNY · Sep 8, 2011 · 35.26 ft · Major · its highest
  • BloomsburgPA · Sep 9, 2011 · 32.75 ft · Major · its highest
  • DanvillePA · Sep 9, 2011 · 31.55 ft · Major
  • TowandaPA · Sep 8, 2011 · 30.52 ft · Major
  • WaverlyPA · Sep 8, 2011 · 26.67 ft · Major · its highest

Gauges on the Susquehanna River

Flood gauges sharing the river's name, linked within 80 miles of one another.

Flood gauges on the Susquehanna River
BainbridgeNY15.027.05 ft, Jun 29, 20062
BinghamtonNY14.025.73 ft, Sep 8, 201112
BloomsburgPA19.032.75 ft, Sep 9, 20115
ConklinNY12.025.02 ft, Jun 28, 20062
Conowingo Dam this gaugeMD23.536.83 ft, Jun 24, 19725
DanvillePA20.032.32 ft, Jun 24, 19723
HarrisburgPA17.033.27 ft, Jun 24, 19728
MariettaPA49.064.54 ft, Jun 23, 19729
MeshoppenPA27.044.48 ft, Sep 8, 20112
OwegoNY30.039.62 ft, Sep 8, 20113
SidneyNY979.5988.30 ft, Jun 28, 20062
SunburyPA24.035.80 ft, Jun 24, 19721
TowandaPA16.033.43 ft, Jun 24, 19723
UnadillaNY11.017.72 ft, Jun 29, 20065
VestalNY18.035.26 ft, Sep 8, 20118
Wilkes BarrePA22.042.66 ft, Sep 9, 201115
WindsorNY17.024.27 ft, Jun 29, 20063
WaverlyPA13.026.67 ft, Sep 8, 20117

Other gauges in Harford County

Flood gauges in Harford County
Bel Air9.011.15 ft, Aug 20, 20160
Chesapeake Bay at Havre de Grace (IN MLLW)4.06.93 ft, Jan 10, 20240
Rocks State Park11.017.70 ft, Aug 23, 19334
Darlington10.013.98 ft, Apr 30, 20140
Belcamp9.011.11 ft, Aug 31, 20180
Bel Air6.06.73 ft, Jun 3, 20210
Bel Air9.011.35 ft, Jun 28, 20060
Benson9.011.60 ft, Jun 22, 19720

Harford County: every hazard · River floods across the country · Maryland

NOAA National Water Prediction Service, gauge CNWM2, retrieved October 30, 2026. Stages in feet on the gauge's own datum, not elevation. Crests are as the National Weather Service lists them; preliminary values may be revised.