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Monongahela River at Elizabeth Lock and Dam

Highest listed crest 32.50 ftFlood stage 20.0 ft49 crests since 1936

The Monongahela River at Elizabeth Lock and Dam crested at major flood stage 9 times among the 49 crests the National Weather Service lists from 1936 to 2024. The highest, 32.50 ft on March 18, 1936, was major flooding, 12.50 feet above flood stage. 3 other gauges on the Monongahela River crested above flood stage within a week of it, 1 at its own highest listed crest.

The gauge

Highest listed crest
32.50 ft
March 18, 1936
Flood stage
20.0 ft
Major flooding from 26.0 ft
Crests at major
9
17th of 170 gauges in Pennsylvania
Most recent flood crest
April 4, 2024
24.54 ft, moderate flooding
Location
Allegheny County
Near Jefferson Hills (3.2 mi), McKeesport (6.3 mi), West Mifflin (6.6 mi)
Identifiers
NWS ELZP1
USGS 03075070; out of service

Flood stages

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

Flood categories, Monongahela River at Elizabeth Lock and Dam
Action stage16.54Feb 8, 2019The level at which the NWS or its partners begin to take action
Flood stage (minor)20.024Feb 5, 2022Minimal or no property damage, but possibly some public threat
Moderate flood stage23.012Apr 4, 2024Some inundation of structures and roads near the stream
Major flood stage26.09Apr 16, 2007Extensive inundation of structures and roads

Every listed crest

49 crests from 1936 to 2024. Filled: at or above flood stage. Hover a crest for its date and stage.

Listed crests at the Monongahela River at Elizabeth Lock and Dam, 1936 to 2024 1520253035ft Flood stage 20.0 ftMajor 26.0 ft Mar 18, 1936: 32.50 ft, major floodingDec 30, 1942: 24.80 ft, moderate floodingOct 16, 1954: 28.50 ft, major floodingMar 6, 1963: 26.50 ft, major floodingMar 20, 1963: 23.60 ft, moderate floodingMar 7, 1967: 28.30 ft, major floodingMay 25, 1968: 25.60 ft, moderate floodingJun 24, 1972: 29.00 ft, major floodingJan 12, 1974: 24.40 ft, moderate floodingJun 24, 1974: 20.00 ft, minor floodingApr 26, 1975: 20.20 ft, minor floodingOct 10, 1976: 20.20 ft, minor floodingJan 27, 1978: 23.90 ft, moderate floodingDec 9, 1978: 22.40 ft, minor floodingFeb 26, 1979: 23.40 ft, moderate floodingMar 5, 1979: 21.10 ft, minor floodingAug 19, 1980: 21.70 ft, minor floodingJun 7, 1981: 21.60 ft, minor floodingNov 6, 1985: 31.60 ft, major floodingFeb 5, 1986: 21.30 ft, minor floodingDec 19, 1990: 21.30 ft, minor floodingDec 31, 1990: 20.70 ft, minor floodingJan 29, 1994: 22.80 ft, minor floodingFeb 10, 1994: 23.70 ft, moderate floodingJan 20, 1996: 30.30 ft, major floodingFeb 19, 2000: 27.60 ft, major floodingMar 21, 2002: 20.20 ft, minor flooding; 83,473 cubic feet per secondFeb 24, 2003: 20.60 ft, minor floodingNov 20, 2003: 24.70 ft, moderate flooding; 121,000 cubic feet per secondFeb 7, 2004: 21.30 ft, minor flooding; 92,000 cubic feet per secondMar 7, 2004: 20.00 ft, minor flooding; 81,621 cubic feet per secondApr 14, 2004: 20.85 ft, minor flooding; 87,900 cubic feet per secondSep 18, 2004: 19.50 ft, action stage; 71,900 cubic feet per secondJan 6, 2005: 21.23 ft, minor flooding; 91,100 cubic feet per secondJan 12, 2005: 19.60 ft, action stage; 76,600 cubic feet per secondMar 29, 2005: 20.00 ft, minor floodingApr 16, 2007: 26.77 ft, major flooding; 72,810 cubic feet per secondDec 14, 2007: 22.05 ft, minor flooding; 97,313 cubic feet per secondJun 5, 2008: 19.31 ft, action stage; 72,460 cubic feet per secondJan 26, 2010: 20.60 ft, minor flooding; 85,422 cubic feet per secondMar 5, 2015: 23.77 ft, moderate flooding; 113,168 cubic feet per secondJul 30, 2017: 24.05 ft, moderate flooding; 115,400 cubic feet per secondFeb 17, 2018: 24.53 ft, moderate floodingSep 11, 2018: 22.87 ft, minor floodingFeb 8, 2019: 18.10 ft, action stage; 61,560 cubic feet per secondDec 18, 2019: 20.05 ft, minor flooding; 80,660 cubic feet per secondMar 2, 2021: 22.87 ft, minor flooding; 104,903 cubic feet per secondFeb 5, 2022: 20.17 ft, minor flooding; 81,703 cubic feet per secondApr 4, 2024: 24.54 ft, moderate flooding; 119,840 cubic feet per second Highest, 32.50 ft, Mar 18, 1936 19401960198020002020

Crests at or above flood stage, by decade

Crests at or above flood stage per decade, Monongahela River at Elizabeth Lock and Dam 1930s: 1 1940s: 1 1950s: 1 1960s: 4 1970s: 9 1980s: 4 1990s: 5 2000s: 11 11 2010s: 6 2020s: 3 1930s1940s1950s1960s1970s1980s1990s2000s2010s2020s
  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, Monongahela River at Elizabeth Lock and Dam
1Mar 18, 193632.50+12.50Major—
2Nov 6, 198531.60+11.60Major—
3Jan 20, 199630.30+10.30Major—
4Jun 24, 197229.00+9.00Major—
5Oct 16, 195428.50+8.50Major—
6Mar 7, 196728.30+8.30Major—
7Feb 19, 200027.60+7.60Major—
8Apr 16, 200726.77+6.77Major72,810
9Mar 6, 196326.50+6.50Major—
10May 25, 196825.60+5.60Moderate—
11Dec 30, 194224.80+4.80Moderate—
12Nov 20, 200324.70+4.70Moderate121,000
13Apr 4, 202424.54+4.54Moderate119,840
14Feb 17, 201824.53+4.53Moderate—
15Jan 12, 197424.40+4.40Moderate—
16Jul 30, 201724.05+4.05Moderate115,400
17Jan 27, 197823.90+3.90Moderate—
18Mar 5, 201523.77+3.77Moderate113,168
19Feb 10, 199423.70+3.70Moderate—
20Mar 20, 196323.60+3.60Moderate—
21Feb 26, 197923.40+3.40Moderate—
22Sep 11, 201822.87+2.87Minor—
23Mar 2, 202122.87+2.87Minor104,903
24Jan 29, 199422.80+2.80Minor—
25Dec 9, 197822.40+2.40Minor—
26Dec 14, 200722.05+2.05Minor97,313
27Aug 19, 198021.70+1.70Minor—
28Jun 7, 198121.60+1.60Minor—
29Feb 5, 198621.30+1.30Minor—
30Dec 19, 199021.30+1.30Minor—
31Feb 7, 200421.30+1.30Minor92,000
32Jan 6, 200521.23+1.23Minor91,100
33Mar 5, 197921.10+1.10Minor—
34Apr 14, 200420.85+0.85Minor87,900
35Dec 31, 199020.70+0.70Minor—
36Feb 24, 200320.60+0.60Minor—
37Jan 26, 201020.60+0.60Minor85,422
38Apr 26, 197520.20+0.20Minor—
39Oct 10, 197620.20+0.20Minor—
40Mar 21, 200220.20+0.20Minor83,473
41Feb 5, 202220.17+0.17Minor81,703
42Dec 18, 201920.05+0.05Minor80,660
43Jun 24, 197420.000.00Minor—
44Mar 7, 200420.000.00Minor81,621
45Mar 29, 200520.000.00Minor—
46Jan 12, 200519.60−0.40Action76,600
47Sep 18, 200419.50−0.50Action71,900
48Jun 5, 200819.31−0.69Action72,460
49Feb 8, 201918.10−1.90Action61,560

The worst floods along the Monongahela River

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

March 18, 1936: 32.50 ft here, major flooding

November 6, 1985: 31.60 ft here, major flooding

January 20, 1996: 30.30 ft here, major flooding

Gauges on the Monongahela River

In USGS station-number order, which runs downstream within a river basin.

Flood gauges on the Monongahela River
Morgantown Lock and DamWV22.027.70 ft, Nov 6, 19851
Point Marion Lock and Dam (lower pool)PA26.034.00 ft, Jan 19, 19967
Grays Landing Lock and DamPA21.036.00 ft, Jul 1, 18883
Maxwell Lock and Dam (lower pool)PA32.044.40 ft, Nov 5, 19855
Charleroi Lock and DamPA28.042.70 ft, Nov 5, 198514
Elizabeth Lock and Dam this gaugePA20.032.50 ft, Mar 18, 19369
Braddock Lock and DamPA22.035.30 ft, Mar 18, 19368

Other gauges in Allegheny County

Flood gauges in Allegheny County
C.W. Bill Young Lock and Dam17.031.10 ft, Mar 18, 19362
Natrona Lock and Dam21.032.10 ft, Mar 18, 19365
Sharpsburg Lock and Dam21.026.90 ft, Jun 24, 19721
Carnegie20.025.05 ft, Sep 18, 20041
Girty's Run11.013.56 ft, Jul 5, 20180
Etna9.010.28 ft, May 30, 19860
Braddock Lock and Dam22.035.30 ft, Mar 18, 19368
Dashields Lock and Dam25.042.80 ft, Mar 18, 19365
Pittsburgh22.046.00 ft, Mar 18, 193622
Etna13.014.60 ft, Sep 1, 20210
Turtle Creek6.011.34 ft, Jun 18, 20091
Sutersville20.032.50 ft, Oct 16, 195412

Allegheny County: every hazard · River floods across the country · Pennsylvania

NOAA National Water Prediction Service, gauge ELZP1, 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.