Total bridges
278
Public highway bridges in Whiteside County
County profile · official public datasets
Whiteside County, IL
278 public highway bridges tracked in the FHWA National Bridge Inventory: 19.1% rated Good, 72.3% Fair, 8.6% Poor.
- 278
- Public bridges
- 19.1%
- Good condition
- 8.6%
- Poor condition
The verdict
According to the Federal Highway Administration's 2024 National Bridge Inventory.
Whiteside County posts a higher-than-median Poor-condition share among rated counties in the state across mid-size county bridge inventory.
- 64th
- of 102 on Poor share
- 8.6%
- Poor-condition share
- 278
- public highway bridges
- 1977
- avg year built
Poor is an FHWA condition category from the lowest applicable component rating (4 or below), not a live crossing-safety or closure decision. Rankings cover counties with at least five public highway bridges.
Whiteside County Bridge Snapshot
According to the Federal Highway Administration's 2024 National Bridge Inventory, Whiteside County ranks #64 of 102 Illinois counties with at least 5 public highway bridges on Poor-condition share (lower share ranks better; currently 8.6%). Whiteside County, Illinois contains 278 public highway bridges. Roughly 19.1% are rated “Good,” 72.3% “Fair,” and 8.6% “Poor.” Poor means the lowest applicable deck, superstructure, substructure, or culvert rating is 4 or below on the 0–9 NBI scale. It is a condition category, not a live safety or closure decision.
Responsible agencies inspect covered bridges on risk-based intervals under current NBIS rules and submit inventory data to FHWA annually. The list below shows every NBI-tracked bridge in the county. Use the “Sort by” controls to change the ordering, and click any row for its reported inspection date, traffic count, and condition fields.
Source: FHWA National Bridge Inventory. See methodology for full definitions.
Good condition
19.1%
53 of 278 rated 7-9
Fair condition
72.3%
201 of 278 rated 5-6
Poor condition
8.6%
24 of 278 rated 4 or below
In-state Poor-share rank
#64 of 102
Among Illinois counties with 5+ bridges, lower share ranks better
Condition distribution
Share of 278 NBI-tracked bridges by lowest applicable component rating.
Good 19.1% (53)
Fair 72.3% (201)
Poor 8.6% (24)
Whiteside County's Poor-condition bridges carry 10,995 vehicle crossings a day
That is 1.9% of the county's reported daily bridge traffic on 8.3% of its bridges: Poor-condition structures carry less traffic than their share of the inventory. Each Poor bridge averages 478 crossings a day against 2,893 for a Good-condition one. A Poor rating is a condition category, not a closure or a live safety judgement; it means the lowest applicable component rating is 4 or below.
Computed over the 277 of 278 bridges in this county that report an average daily traffic count. Source: FHWA National Bridge Inventory, 2024 release.
47.1% of Whiteside County's bridges have passed the 50-year mark
131 of the 278 bridges with a recorded construction year were built in 1974 or earlier. Age alone is not a defect: a well-maintained older bridge can rate Good, and 19.1% of this county's inventory does. Even so, this older cohort is the population from which future Poor ratings are drawn, which is why the age profile below matters alongside the condition split above.
Cutoff derives from the 2024 release year minus a 50-year design life. Source: FHWA National Bridge Inventory, 2024 release.
One structure carries 16.4% of the county's Poor-condition bridge traffic
IL 78 over I-88, built 1974, carries 1,800 vehicles a day, the most of any Poor-rated structure here. The county's Poor-condition exposure is concentrated rather than evenly spread, so the 24-bridge count understates how much of the daily burden sits on a single crossing.
Share is of the 10,995 daily crossings on Poor-rated bridges that report a traffic count. Source: FHWA National Bridge Inventory, 2024 release.
When Whiteside County's bridges were built
278 bridges with a recorded construction year, grouped by decade
- 1900s 1
1900–1909
1 bridges
- 1920s 4
1920–1929
4 bridges
- 1930s 6
1930–1939
6 bridges
- 1940s 9
1940–1949
9 bridges
- 1950s 30
1950–1959
30 bridges
- 1960s
1960–1969
37 bridges
- 1970s
1970–1979
76 bridges
- 1980s
1980–1989
45 bridges
- 1990s
1990–1999
33 bridges
- 2000s 21
2000–2009
21 bridges
- 2010s 13
2010–2019
13 bridges
- 2020s 3
2020–2029
3 bridges
What this shows Construction peaked in the 1970s, when 76 of the county's bridges still in the inventory were built, which is 27.3% of those with a recorded year. That cohort is now 45 to 54 years old in the 2024 inventory. Its average build year (1977) matches the Illinois average (1979).
How Whiteside County compares with Illinois's closest counties by inventory size
The 5 Illinois counties nearest Whiteside County in number of bridges, with their condition splits. Its 8.6% Poor share is the 3rd-lowest of these 6. Its average build year of 1977 against a peer-group mean of 1981 is in line with the group.
Showing the 5 closest of 101 Illinois counties eligible for comparison.
| County | Bridges | Good | Fair | Poor | Avg. built |
|---|---|---|---|---|---|
| Hancock County | 292 | 41.8% | 38% | 20.2% | 1977 |
| Edgar County | 278 | 50.7% | 45.3% | 4% | 1977 |
| Whiteside County (this page) | 278 | 19.1% | 72.3% | 8.6% | 1977 |
| Rock Island County | 272 | 46% | 49.3% | 4.8% | 1983 |
| Grundy County | 269 | 40.5% | 32.7% | 26.8% | 1984 |
| Wayne County | 266 | 54.1% | 36.8% | 9% | 1982 |
Each share is of that county's own total tracked bridges; peers are the counties with 5 or more bridges whose inventory size is closest to Whiteside County's. Source: FHWA National Bridge Inventory, 2024 release.
Nationwide counties with similar inventory size or average build year
Two NBI-derived peer sets for Whiteside County, both outside Illinois so the neighborhoods are not the same-state size table above.
Similar inventory size
Nearest county inventories outside IL (278 bridges here).
- Elkhart County, IN · 278 bridges
- Vanderburgh County, IN · 279 bridges
- Navajo County, AZ · 277 bridges
- Delaware County, IN · 277 bridges
Similar average build year
Nearest mean year-built outside IL (1977 here).
- San Diego County, CA · avg 1977 · 1,632 bridges
- King County, WA · avg 1977 · 1,238 bridges
- Riverside County, CA · avg 1977 · 1,117 bridges
- Shelby County, TN · avg 1977 · 1,077 bridges
Source: FHWA National Bridge Inventory, 2024 release. Peers floor at 10 bridges so stub inventories cannot own the match.
Fair-condition bridges (201)
OAK GROVE AVENUE
FairOver: UNNAMED CREEK
0.3 M S OF ST MARYS, Whiteside, IL
Built 1982 Load: 32.4 t ADT: 950
MATZNICK ROAD
FairOver: COUNTY DITCH NO.1
2 MI. NW TAMPICO, Whiteside, IL
Built 1990 Load: 32.4 t ADT: 125
MASON ROAD
FairOver: BR OF ROCK CREEK
3 MI SW MORRISON, Whiteside, IL
Built 1978 Load: 32.4 t ADT: 50
HENRY ROAD
FairOver: BRANCH OF ROCK CREEK
1 MI. W. OF MORRISON, Whiteside, IL
Built 1989 Load: 32.4 t ADT: 575
COVELL RD
FairOver: OTTER CREEK
8 MI NW OF MORRISON, Whiteside, IL
Built 1980 Load: 32.4 t ADT: 25
BLINK ROAD
FairOver: OTTER CREEK
3 MI N.E. OF FULTON, Whiteside, IL
Built 1991 Load: 32.4 t ADT: 100
CREAMERY RD
FairOver: TRIB TO SPRING BROOK
4 MI NW OF MORRISON, Whiteside, IL
Built 2011 Load: 32.4 t ADT: 50
ILL 78
FairOver: STREAM
2.5 MI S OF MORRISON, Whiteside, IL
Built 1979 Load: 32.7 t ADT: 1,800
HAHNAMAN RD
FairOver: WINNEBAGO DRAINAGE D
1 MI.N OF DEER GROVE, Whiteside, IL
Built 1963 Load: 32.7 t ADT: 250
MOLINE RD
FairOver: MEREDOSIA CREEK
ROCK ISLAND CO LINE, Whiteside, IL
Built 2009 Load: 33.4 t ADT: 1,600
HURD RD
FairOver: WINNEBAGO DITCH
1 MI SW DEER GROVE, Whiteside, IL
Built 1980 Load: 33.4 t ADT: 75
HOOVER RD.
FairOver: SUGAR CREEK
2 MI N. STERLING, Whiteside, IL
Built 1967 Load: 33.4 t ADT: 675
CH 17 WILMOT RD
FairOver: I-88
3.0 MI. NE. ERIE, Whiteside, IL
Built 1975 Load: 33.7 t ADT: 200
US 30
FairOver: I&M FEEDER CANAL
0.3 MI E. OF IL 40, Whiteside, IL
Built 1990 Load: 33.7 t ADT: 7,350
COVELL ROAD
FairOver: ROCK CREEK
5 MI NE OF MORRISON, Whiteside, IL
Built 1989 Load: 33.7 t ADT: 35
YORKTOWN ROAD
FairOver: I-88
3 MI NE LYNDON, Whiteside, IL
Built 1974 Load: 34.0 t ADT: 100
HURD RD
FairOver: ROCK RIVER
AT HILLSDALE, Whiteside, IL
Built 1953 Load: 34.0 t ADT: 600
COVELL RD
FairOver: LITTLE ROCK CREEK
7 MI N MORRISON, Whiteside, IL
Built 1980 Load: 34.0 t ADT: 100
FULFS ROAD
FairOver: SPRING CREEK
4 MI NW OF STERLING, Whiteside, IL
Built 1956 Load: 34.3 t ADT: 400
KENNEDY RD
FairOver: CEDAR CREEK
2 MI NE ALBANY, Whiteside, IL
Built 1957 Load: 34.3 t ADT: 600
LYNDON ROAD
FairOver: FRENCH CREEK
0.9 MI N JCT US 30, Whiteside, IL
Built 2002 Load: 34.3 t ADT: 800
CAPP ROAD
FairOver: LITTLE ROCK CREEK
5 MI N OF MORRISON, Whiteside, IL
Built 1977 Load: 34.3 t ADT: 100
HOLLY RD.
FairOver: CATTAIL CREEK
1 MI S OF FULTON, Whiteside, IL
Built 1988 Load: 34.7 t ADT: 450
YAGER ROAD
FairOver: BR OF ROCK RIVER
1.5 MI NE LYNDON, Whiteside, IL
Built 1987 Load: 34.7 t ADT: 125
FULFS RD
FairOver: SUGAR CREEK
2.5 MI N. STERLING, Whiteside, IL
Built 1965 Load: 34.7 t ADT: 900
YORKTOWN ROAD
FairOver: BR OF ROCK RIVER
3 MI NE LYNDON, Whiteside, IL
Built 1983 Load: 35.0 t ADT: 100
US 30 SPUR N B
FairOver: I-88
3.5 MI W ROCK FALLS, Whiteside, IL
Built 1972 Load: 35.3 t ADT: 4,100
I-88 WB
FairOver: BN RR (ABANDON)
.5 MI S US 30, Whiteside, IL
Built 1972 Load: 35.3 t ADT: 6,600
SPRING VALLEY ROAD
FairOver: OTTER CREEK
6 MI NE OF FULTON, Whiteside, IL
Built 1964 Load: 35.3 t ADT: 100
SPRING VALLEY RD
FairOver: JOHNSON CREEK
2 MI NE FULTON, Whiteside, IL
Built 1982 Load: 35.3 t ADT: 50
US 30 SPUR S B
FairOver: I-88
3.5 MI W ROCK FALLS, Whiteside, IL
Built 1972 Load: 36.0 t ADT: 4,100
I-88 EB
FairOver: BN RR (ABANDON)
.5 MI S US 30, Whiteside, IL
Built 1972 Load: 36.0 t ADT: 6,600
BURTON ROAD
FairOver: ELKHORN CREEK
9 MI N OF STERLING, Whiteside, IL
Built 1953 Load: 36.0 t ADT: 25
ILL 40
FairOver: COON CREEK DITCH
1.2 MI N JCT ILL 172, Whiteside, IL
Built 1972 Load: 36.3 t ADT: 3,400
PENROSE RD.
FairOver: SPRING CREEK
1.5 MI. S.E. COLETA, Whiteside, IL
Built 1964 Load: 36.3 t ADT: 50
IL 84
FairOver: JOHNSON CREEK
2.5 M N ILL 136, Whiteside, IL
Built 1980 Load: 36.6 t ADT: 5,500
MELVIN ROAD
FairOver: HOWLAND CREEK
2 MI E OF ROCK FALLS, Whiteside, IL
Built 1960 Load: 36.6 t ADT: 650
SCIENCE RIDGE ROAD
FairOver: ELKHORN CREEK
1 MI NW OF STERLING, Whiteside, IL
Built 1958 Load: 36.6 t ADT: 2,300
FREEPORT RD
FairOver: JORDON CREEK
6 MI N STERLING, Whiteside, IL
Built 1953 Load: 36.9 t ADT: 1,800
ILL RT 84
FairOver: SPRING CREEK
.5 MI N ALBANY, Whiteside, IL
Built 1932 Load: 37.3 t ADT: 4,050
IL 78
FairOver: ROCK RIVER
N EDGE PROPHETSTOWN, Whiteside, IL
Built 1994 Load: 37.3 t ADT: 2,950
CLARK RD
FairOver: LITTLE ROCK CREEK
8.0 MI N MORRISON, Whiteside, IL
Built 1958 Load: 37.3 t ADT: 50
PENROSE RD
FairOver: JORDAN CREEK
6 MI N OF STERLING, Whiteside, IL
Built 1983 Load: 37.9 t ADT: 125
US RT 30
FairOver: ELKHORN CREEK
3.5 MI W ROCK FALLS, Whiteside, IL
Built 1940 Load: 38.2 t ADT: 5,300
MOLINE ROAD
FairOver: DRAINAGE DITCH
3 MI NE LYNDON, Whiteside, IL
Built 2006 Load: 38.2 t ADT: 1,400
YORKTOWN ROAD
FairOver: COUNTY DITCH NO 2
4.5 MI W OF TAMPICO, Whiteside, IL
Built 1955 Load: 38.2 t ADT: 100
US 30
FairOver: UNION PACIFIC RR
2.5 MI W OF MORRISON, Whiteside, IL
Built 1946 Load: 38.6 t ADT: 5,550
I-88 EB
FairOver: ROCK CREEK
4.5 MI. NE. ERIE, Whiteside, IL
Built 1975 Load: 38.6 t ADT: 6,550
I-88 WB
FairOver: ROCK CREEK
4.5 MI. NE. ERIE, Whiteside, IL
Built 1975 Load: 38.6 t ADT: 6,550
I-88 EB
FairOver: TR 136 A / HENRY RD
1.5 MI W ILL 78, Whiteside, IL
Built 1975 Load: 38.6 t ADT: 6,550
Read our methodology - how this data is sourced, computed, and verified.
Related
Data sourced from official public datasets. See our methodology for details. Retrieved and formatted by PlainBridges
Every figure on PlainBridges is rendered directly from federal source data, no number is typed in by an editor. This page draws directly on federal source data, no figure is typed in by an editor. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error. NBI condition categories reflect the latest reported inventory record, not a live safety, closure, or travel decision.