Search
Menu

Explore

Hazards

Analysis

Rankings

Reference

Rock River at Byron

Highest listed crest 17.80 ftFlood stage 13.0 ft40 crests since 1959

The Rock River at Byron crested at major flood stage 5 times among the 40 crests the National Weather Service lists from 1959 to 2024. The highest, 17.80 ft on April 20, 1973, was major flooding, 4.80 feet above flood stage. 7 other gauges on the Rock River crested above flood stage within a week of it, 1 at its own highest listed crest.

The gauge

Highest listed crest
17.80 ft
April 20, 1973
Flood stage
13.0 ft
Major flooding from 16.0 ft
Crests at major
5
56th of 177 gauges in Illinois
Most recent flood crest
July 16, 2024
13.84 ft, minor flooding
Location
Ogle County
Near Rockford (13.6 mi)

Flood stages

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

Flood categories, Rock River at Byron
Action stage10.512Jun 24, 2024The level at which the NWS or its partners begin to take action
Flood stage (minor)13.07Jul 16, 2024Minimal or no property damage, but possibly some public threat
Moderate flood stage14.011Oct 4, 2019Some inundation of structures and roads near the stream
Major flood stage16.05Mar 16, 2019Extensive inundation of structures and roads

Every listed crest

40 crests from 1959 to 2024. Filled: at or above flood stage. Hover a crest for its date and stage.

Listed crests at the Rock River at Byron, 1959 to 2024 81012141618ft Flood stage 13.0 ftMajor 16.0 ft Apr 5, 1959: 14.70 ft, moderate floodingApr 20, 1973: 17.80 ft, major floodingMar 25, 1975: 15.00 ft, moderate floodingMar 21, 1979: 14.70 ft, moderate floodingJun 14, 2000: 16.12 ft, major flooding; 35,400 cubic feet per secondFeb 25, 2001: 11.74 ft, action stage; 21,000 cubic feet per secondJun 5, 2002: 14.67 ft, moderate flooding; 30,800 cubic feet per secondMay 13, 2003: 8.11 ft, below flood stage; 9,290 cubic feet per secondJun 13, 2004: 13.19 ft, minor flooding; 26,100 cubic feet per secondJan 15, 2005: 12.30 ft, action stageFeb 15, 2005: 11.08 ft, action stage; 18,400 cubic feet per secondMar 14, 2006: 8.67 ft, below flood stage; 11,200 cubic feet per secondAug 25, 2007: 15.52 ft, moderate flooding; 34,500 cubic feet per secondJun 15, 2008: 14.81 ft, moderate flooding; 30,500 cubic feet per secondMar 11, 2009: 13.66 ft, minor flooding; 27,900 cubic feet per secondJul 25, 2010: 16.50 ft, major flooding; 37,700 cubic feet per secondMar 24, 2011: 10.49 ft, below flood stage; 16,000 cubic feet per secondNov 10, 2011: 8.99 ft, below flood stage; 12,700 cubic feet per secondApr 20, 2013: 17.08 ft, major flooding; 40,100 cubic feet per secondJul 2, 2014: 11.51 ft, action stage; 19,200 cubic feet per secondJun 17, 2015: 11.54 ft, action stage; 19,300 cubic feet per secondJun 30, 2017: 12.68 ft, action stage; 23,200 cubic feet per secondJul 22, 2017: 15.38 ft, moderate flooding; 33,300 cubic feet per secondFeb 22, 2018: 15.15 ft, moderate flooding; 32,300 cubic feet per secondJun 21, 2018: 12.86 ft, action stage; 23,900 cubic feet per secondJun 27, 2018: 12.82 ft, action stage; 23,800 cubic feet per secondSep 5, 2018: 14.28 ft, moderate flooding; 29,000 cubic feet per secondOct 8, 2018: 15.67 ft, moderate flooding; 33,000 cubic feet per secondMar 16, 2019: 16.64 ft, major flooding; 38,500 cubic feet per secondMay 31, 2019: 13.00 ft, minor flooding; 24,400 cubic feet per secondSep 15, 2019: 13.53 ft, minor flooding; 26,400 cubic feet per secondOct 4, 2019: 14.42 ft, moderate flooding; 29,700 cubic feet per secondMar 29, 2020: 13.06 ft, minor flooding; 24,600 cubic feet per secondMay 18, 2020: 13.11 ft, minor flooding; 24,700 cubic feet per secondDec 28, 2022: 10.32 ft, below flood stage; 8,340 cubic feet per secondApr 5, 2023: 11.67 ft, action stage; 19,600 cubic feet per secondJan 28, 2024: 10.61 ft, action stage; 11,000 cubic feet per secondApr 4, 2024: 12.47 ft, action stage; 22,400 cubic feet per secondJun 24, 2024: 11.23 ft, action stage; 17,900 cubic feet per secondJul 16, 2024: 13.84 ft, minor flooding; 27,400 cubic feet per second Highest, 17.80 ft, Apr 20, 1973 1960197019801990200020102020

Crests at or above flood stage, by decade

Crests at or above flood stage per decade, Rock River at Byron 1950s: 1 1960s: 0 1970s: 3 1980s: 0 1990s: 0 2000s: 6 2010s: 10 10 2020s: 3 1950s1960s1970s1980s1990s2000s2010s2020s
  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, Rock River at Byron
1Apr 20, 197317.80+4.80Major—
2Apr 20, 201317.08+4.08Major40,100
3Mar 16, 201916.64+3.64Major38,500
4Jul 25, 201016.50+3.50Major37,700
5Jun 14, 200016.12+3.12Major35,400
6Oct 8, 201815.67+2.67Moderate33,000
7Aug 25, 200715.52+2.52Moderate34,500
8Jul 22, 201715.38+2.38Moderate33,300
9Feb 22, 201815.15+2.15Moderate32,300
10Mar 25, 197515.00+2.00Moderate—
11Jun 15, 200814.81+1.81Moderate30,500
12Apr 5, 195914.70+1.70Moderate—
13Mar 21, 197914.70+1.70Moderate—
14Jun 5, 200214.67+1.67Moderate30,800
15Oct 4, 201914.42+1.42Moderate29,700
16Sep 5, 201814.28+1.28Moderate29,000
17Jul 16, 202413.84+0.84Minor27,400
18Mar 11, 200913.66+0.66Minor27,900
19Sep 15, 201913.53+0.53Minor26,400
20Jun 13, 200413.19+0.19Minor26,100
21May 18, 202013.11+0.11Minor24,700
22Mar 29, 202013.06+0.06Minor24,600
23May 31, 201913.000.00Minor24,400
24Jun 21, 201812.86−0.14Action23,900
25Jun 27, 201812.82−0.18Action23,800
26Jun 30, 201712.68−0.32Action23,200
27Apr 4, 202412.47−0.53Action22,400
28Jan 15, 200512.30−0.70Action—
29Feb 25, 200111.74−1.26Action21,000
30Apr 5, 202311.67−1.33Action19,600
31Jun 17, 201511.54−1.46Action19,300
32Jul 2, 201411.51−1.49Action19,200
33Jun 24, 202411.23−1.77Action17,900
34Feb 15, 200511.08−1.92Action18,400
35Jan 28, 202410.61−2.39Action11,000
36Mar 24, 201110.49−2.51Below flood stage16,000
37Dec 28, 202210.32−2.68Below flood stage8,340
38Nov 10, 20118.99−4.01Below flood stage12,700
39Mar 14, 20068.67−4.33Below flood stage11,200
40May 13, 20038.11−4.89Below flood stage9,290

The worst floods along the Rock River

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

April 20, 1973: 17.80 ft here, major flooding

April 20, 2013: 17.08 ft here, major flooding

  • JoslinIL · Apr 21, 2013 · 19.11 ft · Major
  • Fort AtkinsonWI · Apr 22, 2013 · 18.12 ft · Major
  • MolineIL · Apr 22, 2013 · 16.53 ft · Major · its highest
  • Lake KoshkonongWI · Apr 22, 2013 · 12.35 ft · Major
  • NewvilleWI · Apr 23, 2013 · 8.51 ft · Major · its highest
  • DixonIL · Apr 20, 2013 · 18.16 ft · Moderate
  • RocktonIL · Apr 21, 2013 · 13.46 ft · Moderate
  • Latham ParkIL · Apr 22, 2013 · 12.82 ft · Moderate
  • Lebanon-3 E-Hwy MM bridgeWI · Apr 21, 2013 · 12.54 ft · Moderate
  • JeffersonWI · Apr 20, 2013 · 12.31 ft · Moderate

March 16, 2019: 16.64 ft here, major flooding

Gauges on the Rock River

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

Flood gauges on the Rock River
AftonWI9.013.51 ft, Jun 21, 20083
Byron this gaugeIL13.017.80 ft, Apr 20, 19735
ComoIL12.515.64 ft, Jul 23, 20170
DixonIL16.020.50 ft, Apr 20, 19731
Fort AtkinsonWI16.020.90 ft, Jun 15, 20082
JeffersonWI10.015.64 ft, Jun 19, 20081
Lake KoshkonongWI10.015.13 ft, Jun 21, 20086
Latham ParkIL9.014.70 ft, Mar 26, 19753
Lebanon-3 E-Hwy MM bridgeWI10.014.01 ft, Jun 15, 20081
MolineIL12.016.53 ft, Apr 22, 201334
NewvilleWI6.58.51 ft, Apr 23, 20131
Rockford (Auburn Street)IL6.010.00 ft, Apr 20, 18811
Rockford (Fordam Dam)IL4.06.50 ft, Apr 20, 18811
RocktonIL10.015.54 ft, Mar 25, 19754
WatertownWI5.57.81 ft, Jun 13, 20082
JoslinIL12.019.24 ft, Jun 7, 200224

Ogle County: every hazard · River floods across the country · Illinois

NOAA National Water Prediction Service, gauge BYRI2, 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.