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Little Lehigh Creek at Allentown

Highest listed crest 12.69 ftFlood stage 8.0 ft16 crests since 1987

The Little Lehigh Creek at Allentown crested at major flood stage 1 time among the 16 crests the National Weather Service lists from 1987 to 2021. The highest, 12.69 ft on August 4, 2020, was major flooding, 4.69 feet above flood stage. 1 other gauge on the Little Lehigh Creek crested above flood stage within a week of it, 1 at its own highest listed crest.

The gauge

Highest listed crest
12.69 ft
August 4, 2020; 14,474 cubic feet per second
Flood stage
8.0 ft
Major flooding from 12.0 ft
Crests at major
1
103rd of 170 gauges in Pennsylvania
Most recent flood crest
September 2, 2021
9.60 ft, minor flooding
Location
Lehigh County
Near Allentown (0.3 mi), Emmaus (4.4 mi), Bethlehem (6.0 mi)

Flood stages

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

Flood categories, Little Lehigh Creek at Allentown
Action stage6.03Apr 3, 2005The level at which the NWS or its partners begin to take action
Flood stage (minor)8.06Sep 2, 2021Minimal or no property damage, but possibly some public threat
Moderate flood stage10.02Oct 8, 2005Some inundation of structures and roads near the stream
Major flood stage12.01Aug 4, 2020Extensive inundation of structures and roads

Every listed crest

16 crests from 1987 to 2021. Filled: at or above flood stage. Hover a crest for its date and stage.

Listed crests at the Little Lehigh Creek at Allentown, 1987 to 2021 468101214ft Flood stage 8.0 ftMajor 12.0 ft Sep 9, 1987: 9.47 ft, minor flooding; 7,370 cubic feet per secondAug 17, 1993: 5.81 ft, below flood stage; 2,760 cubic feet per secondJul 28, 1994: 5.79 ft, below flood stage; 2,390 cubic feet per secondJan 19, 1996: 7.20 ft, action stage; 4,000 cubic feet per secondOct 19, 1996: 8.60 ft, minor flooding; 6,540 cubic feet per secondSep 16, 1999: 8.06 ft, minor flooding; 5,170 cubic feet per secondJun 21, 2003: 6.66 ft, action stage; 3,340 cubic feet per secondSep 18, 2004: 10.65 ft, moderate flooding; 9,680 cubic feet per secondApr 3, 2005: 7.34 ft, action stage; 4,207 cubic feet per secondOct 8, 2005: 11.05 ft, moderate flooding; 10,500 cubic feet per secondMar 11, 2011: 5.21 ft, below flood stage; 1,819 cubic feet per secondAug 28, 2011: 9.88 ft, minor floodingSep 7, 2011: 5.83 ft, below flood stage; 2,430 cubic feet per secondNov 3, 2018: 8.00 ft, minor flooding; 5,083 cubic feet per secondAug 4, 2020: 12.69 ft, major flooding; 14,474 cubic feet per secondSep 2, 2021: 9.60 ft, minor flooding; 7,610 cubic feet per second Highest, 12.69 ft, Aug 4, 2020 1990200020102020

Crests at or above flood stage, by decade

Crests at or above flood stage per decade, Little Lehigh Creek at Allentown 1980s: 1 1990s: 2 2 2000s: 2 2010s: 2 2020s: 2 1980s1990s2000s2010s2020s
  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, Little Lehigh Creek at Allentown
1Aug 4, 202012.69+4.69Major14,474
2Oct 8, 200511.05+3.05Moderate10,500
3Sep 18, 200410.65+2.65Moderate9,680
4Aug 28, 20119.88+1.88Minor—
5Sep 2, 20219.60+1.60Minor7,610
6Sep 9, 19879.47+1.47Minor7,370
7Oct 19, 19968.60+0.60Minor6,540
8Sep 16, 19998.06+0.06Minor5,170
9Nov 3, 20188.000.00Minor5,083
10Apr 3, 20057.34−0.66Action4,207
11Jan 19, 19967.20−0.80Action4,000
12Jun 21, 20036.66−1.34Action3,340
13Sep 7, 20115.83−2.17Below flood stage2,430
14Aug 17, 19935.81−2.19Below flood stage2,760
15Jul 28, 19945.79−2.21Below flood stage2,390
16Mar 11, 20115.21−2.79Below flood stage1,819

The worst floods along the Little Lehigh Creek

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

August 4, 2020: 12.69 ft here, major flooding

  • AllentownPA · Aug 4, 2020 · 12.76 ft · Major · its highest

October 8, 2005: 11.05 ft here, moderate flooding

  • AllentownPA · Oct 8, 2005 · 10.93 ft · Major

September 18, 2004: 10.65 ft here, moderate flooding

  • AllentownPA · Sep 18, 2004 · 10.63 ft · Major

Gauges on the Little Lehigh Creek

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

Flood gauges on the Little Lehigh Creek
TrexlertownPA4.56.74 ft, Jan 10, 20240
AllentownPA5.012.76 ft, Aug 4, 20205
Allentown this gaugePA8.012.69 ft, Aug 4, 20201

Other gauges in Lehigh County

Flood gauges in Lehigh County
Allentown8.011.82 ft, Aug 5, 20202
Bethlehem16.025.90 ft, May 23, 19423
Allentown5.012.76 ft, Aug 4, 20205
Trexlertown4.56.74 ft, Jan 10, 20240
Trexlertown4.56.70 ft, Jan 10, 20240

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

NOAA National Water Prediction Service, gauge APAP1, 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.