Total bridges
179
Public highway bridges in Carroll County
County profile · official public datasets
Carroll County, IL
179 public highway bridges tracked in the FHWA National Bridge Inventory: 37.4% rated Good, 52% Fair, 10.6% Poor.
- 179
- Public bridges
- 37.4%
- Good condition
- 10.6%
- Poor condition
The verdict
According to the Federal Highway Administration's 2024 National Bridge Inventory.
Carroll County posts a higher-than-median Poor-condition share among rated counties in the state across mid-size county bridge inventory.
- 78th
- of 102 on Poor share
- 10.6%
- Poor-condition share
- 179
- public highway bridges
- 1979
- 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.
Carroll County Bridge Snapshot
According to the Federal Highway Administration's 2024 National Bridge Inventory, Carroll County ranks #78 of 102 Illinois counties with at least 5 public highway bridges on Poor-condition share (lower share ranks better; currently 10.6%). Carroll County, Illinois contains 179 public highway bridges. Roughly 37.4% are rated “Good,” 52% “Fair,” and 10.6% “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
37.4%
67 of 179 rated 7-9
Fair condition
52%
93 of 179 rated 5-6
Poor condition
10.6%
19 of 179 rated 4 or below
In-state Poor-share rank
#78 of 102
Among Illinois counties with 5+ bridges, lower share ranks better
Condition distribution
Share of 179 NBI-tracked bridges by lowest applicable component rating.
Good 37.4% (67)
Fair 52% (93)
Poor 10.6% (19)
Carroll County's Poor-condition bridges carry 4,750 vehicle crossings a day
That is 4% of the county's reported daily bridge traffic on 10.6% of its bridges: Poor-condition structures carry less traffic than their share of the inventory. Each Poor bridge averages 250 crossings a day against 573 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 179 of 179 bridges in this county that report an average daily traffic count. Source: FHWA National Bridge Inventory, 2024 release.
31.3% of Carroll County's bridges have passed the 50-year mark
56 of the 179 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 37.4% 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 49.5% of the county's Poor-condition bridge traffic
ARGO FAY ROAD over STREAM, built 1937, carries 2,350 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 19-bridge count understates how much of the daily burden sits on a single crossing.
Share is of the 4,750 daily crossings on Poor-rated bridges that report a traffic count. Source: FHWA National Bridge Inventory, 2024 release.
When Carroll County's bridges were built
179 bridges with a recorded construction year, grouped by decade
- pre-1900 2
Built before 1900
2 bridges
- 1910s 1
1910–1919
1 bridges
- 1920s 9
1920–1929
9 bridges
- 1930s 6
1930–1939
6 bridges
- 1940s 4
1940–1949
4 bridges
- 1950s 14
1950–1959
14 bridges
- 1960s 13
1960–1969
13 bridges
- 1970s
1970–1979
22 bridges
- 1980s
1980–1989
47 bridges
- 1990s
1990–1999
31 bridges
- 2000s 16
2000–2009
16 bridges
- 2010s 11
2010–2019
11 bridges
- 2020s 3
2020–2029
3 bridges
What this shows Construction peaked in the 1980s, when 47 of the county's bridges still in the inventory were built, which is 26.3% of those with a recorded year. That cohort is now 35 to 44 years old in the 2024 inventory. Its average build year (1979) matches the Illinois average (1979).
How Carroll County compares with Illinois's closest counties by inventory size
The 5 Illinois counties nearest Carroll County in number of bridges, with their condition splits. Its 10.6% Poor share is the 5th-lowest of these 6. Its average build year of 1979 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 |
|---|---|---|---|---|---|
| Lawrence County | 185 | 36.2% | 41.1% | 22.7% | 1975 |
| Saline County | 185 | 71.4% | 23.8% | 4.9% | 1985 |
| Jasper County | 181 | 70.7% | 24.3% | 5% | 1982 |
| Carroll County (this page) | 179 | 37.4% | 52% | 10.6% | 1979 |
| Moultrie County | 172 | 39% | 51.2% | 9.9% | 1984 |
| Cumberland County | 169 | 54.4% | 39.1% | 6.5% | 1979 |
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 Carroll 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 Carroll County, both outside Illinois so the neighborhoods are not the same-state size table above.
Similar inventory size
Nearest county inventories outside IL (179 bridges here).
- Graham County, AZ · 179 bridges
- Thomas County, GA · 179 bridges
- Fremont County, IA · 179 bridges
- Morris County, KS · 179 bridges
Similar average build year
Nearest mean year-built outside IL (1979 here).
- Pima County, AZ · avg 1979 · 1,150 bridges
- Jefferson County, KY · avg 1979 · 662 bridges
- Spartanburg County, SC · avg 1979 · 638 bridges
- McPherson County, KS · avg 1979 · 586 bridges
Source: FHWA National Bridge Inventory, 2024 release. Peers floor at 10 bridges so stub inventories cannot own the match.
Fair-condition bridges (93)
E CYCLONE RIDGE RO
FairOver: ROCK CREEK
1 MI S LANARK, Carroll, IL
Built 1954 Load: 17.2 t ADT: 150
N FLORY ROAD
FairOver: WEST FORK
6 MILES EAST LANARK, Carroll, IL
Built 1921 Load: 17.5 t ADT: 25
E COOK ROAD
FairOver: OTTER CREEK
4 MI E CHADWICK, Carroll, IL
Built 1920 Load: 17.5 t ADT: 50
E SCHELL ROAD
FairOver: BRANCH OF ELKHORN CR
2 MI SE MILLEDGEVILL, Carroll, IL
Built 1920 Load: 17.5 t ADT: 150
CITY PARK ROAD
FairOver: CARROLL CREEK
0.10 MI W PARK ENTRN, Carroll, IL
Built 1994 Load: 18.5 t ADT: 125
N OLD GALENA TRAIL
FairOver: BR OF E FK OF PLUM R
2 MI N MT.CARROLL, Carroll, IL
Built 1925 Load: 21.1 t ADT: 100
N LORAN ROUTE
FairOver: BR. E. FK. PLUM RIV
5.7 MI NE MT.CARROLL, Carroll, IL
Built 1955 Load: 21.4 t ADT: 200
W AIRPORT ROAD
FairOver: DRAINAGE DITCH
2 MILES S SAVANNA, Carroll, IL
Built 1955 Load: 21.7 t ADT: 400
KING RD
FairOver: JOHNSON CREEK
6.5 MI SW MT CARROLL, Carroll, IL
Built 1953 Load: 21.7 t ADT: 100
S SUNSHINE ROAD
FairOver: EAGLE CREEK
2 MI NE MILLEDGEVILL, Carroll, IL
Built 1953 Load: 22.0 t ADT: 100
W SCENIC PALISADES
FairOver: CARROLL CREEK
2.5 MI W MT CARROLL, Carroll, IL
Built 1965 Load: 22.7 t ADT: 75
OTTER CREEK DRIVE
FairOver: OTTER CREEK
5 MI W OF BROOKVILLE, Carroll, IL
Built 1962 Load: 22.7 t ADT: 50
E FAIRHAVEN ROAD
FairOver: LITTLE ROCK CREEK
5 MI SW CHADWICK, Carroll, IL
Built 1963 Load: 23.0 t ADT: 100
N MAPLE GROVE RD
FairOver: BR. STRADDLE CREEK
3.5 MI NE LANARK, Carroll, IL
Built 1971 Load: 23.3 t ADT: 50
BROOKVILLE ROAD
FairOver: ROCK CREEK
3 MI NE CHADWICK, Carroll, IL
Built 1967 Load: 24.0 t ADT: 25
W CAMP CREEK ROAD
FairOver: CAMP CREEK
3MI NE PALISADES PAR, Carroll, IL
Built 1952 Load: 24.3 t ADT: 25
W DAVIS ROAD
FairOver: BRANCH OF PLUM R
5 MI NW MT.CARROLL, Carroll, IL
Built 1927 Load: 24.3 t ADT: 50
W CORBETT ROAD
FairOver: BRANCH OF CARROLL CK
1 M NW MT CARROLL, Carroll, IL
Built 1927 Load: 24.3 t ADT: 150
GRANGE ROAD
FairOver: BRANCH OF MIDDLE CR
2 MI NW BROOKVILLE, Carroll, IL
Built 1975 Load: 24.3 t ADT: 75
W YORK CENTER ROAD
FairOver: BR OF JOHNSON CREEK
4 MI NE OF THOMSON, Carroll, IL
Built 1985 Load: 24.3 t ADT: 25
GOOSE ROAD
FairOver: GOOSE CREEK
4 MI SE MILLEDGEVIL., Carroll, IL
Built 1932 Load: 24.3 t ADT: 75
N STONE BRIDGE ROA
FairOver: BR OF STRADDLE CR
.5 MI W LANARK, Carroll, IL
Built 1964 Load: 24.6 t ADT: 225
NORTH MEYERS ROAD
FairOver: BR E FORK PLUM RIVER
3.5 M N MT. CARROLL, Carroll, IL
Built 1899 Load: 25.6 t ADT: 50
E BROOKVILLE ROAD
FairOver: MIDDLE CREEK
5 MI SE LANARK, Carroll, IL
Built 1974 Load: 25.9 t ADT: 225
SCENIC BLUFF RD
FairOver: NO NAME CRK
SW CORN SEC29, Carroll, IL
Built 1945 Load: 26.9 t ADT: 75
E LIVINGGOOD ROAD
FairOver: OTTER CREEK
2.5MI.NW MILLEDGEVIL, Carroll, IL
Built 1958 Load: 26.9 t ADT: 50
MEYERS RD.
FairOver: E. FORK PLUM RIVER
4.5 MI N MT CARROLL, Carroll, IL
Built 1965 Load: 27.2 t ADT: 50
N BLUE MT ROAD
FairOver: E FORK OF PLUM RIVER
4 MI N MT.CARROLL, Carroll, IL
Built 1958 Load: 28.8 t ADT: 10
E WATCH DOG ROAD
FairOver: OTTER CREEK
5.5 MI E CHADWICK, Carroll, IL
Built 1931 Load: 30.8 t ADT: 50
US 52 & ILL 64
FairOver: STRADDLE CREEK
2.9 MI E OF ILL 73, Carroll, IL
Built 1983 Load: 31.1 t ADT: 2,500
TR-38 (W Wacker Rd
FairOver: PLUM RIVER
.25 MI E SAVANNA, Carroll, IL
Built 1977 Load: 32.1 t ADT: 775
IL 73
FairOver: STREAM
0.5 MI. N. OF IL 72, Carroll, IL
Built 1996 Load: 32.4 t ADT: 2,550
ILL 64
FairOver: STREAM
2.6 MI W JCT ILL 78, Carroll, IL
Built 2008 Load: 32.4 t ADT: 3,100
W MESSMER ROAD
FairOver: CAMP CREEK
3 MI NNE SAVANNA, Carroll, IL
Built 1977 Load: 32.4 t ADT: 25
ZION RD - CH 16
FairOver: CAMP CREEK
1.5MI E MISS PALISAD, Carroll, IL
Built 1994 Load: 32.4 t ADT: 150
SKUNK HOLLOW ROAD
FairOver: BR OF E FORK PLUM RV
4.5 M N MT CARROLL, Carroll, IL
Built 1981 Load: 32.4 t ADT: 25
N CENTER DRIVE
FairOver: STRADDLE CREEK
1 MI NE LANARK, Carroll, IL
Built 1978 Load: 32.4 t ADT: 200
STRADDLE CREEK RD
FairOver: STRADDLE CREEK
2 MI E OF IL 73, Carroll, IL
Built 2003 Load: 32.4 t ADT: 250
N GOLD MINE ROAD
FairOver: BR W FORK ELKHORN CR
6.5 M E OF LANARK, Carroll, IL
Built 1982 Load: 32.4 t ADT: 100
N. STANTON RD /TR1
FairOver: LOST CREEK
1.5 MI. N. SHANNON, Carroll, IL
Built 1989 Load: 32.4 t ADT: 350
WACKER RD
FairOver: BNSF RR
SE EDGE OF SAVANNA, Carroll, IL
Built 1996 Load: 32.4 t ADT: 775
OIL VALLEY SCHOOL
FairOver: EAST JOHNSON CREEK
1.5 MI NE ARGO FAY, Carroll, IL
Built 1980 Load: 32.4 t ADT: 200
HICKORY GROVE ROAD
FairOver: BR OF PLUM RIVER
3 MI SE SAVANNA, Carroll, IL
Built 1984 Load: 32.4 t ADT: 25
MILL RD
FairOver: JOHNSON CREEK
1.5 MI S. MT CARROLL, Carroll, IL
Built 1989 Load: 32.4 t ADT: 50
FULRATH MILL RD
FairOver: CARROLL CREEK
2 MI W MT CARROLL, Carroll, IL
Built 1980 Load: 32.4 t ADT: 125
VANBUSKIRK RD
FairOver: STRADDLE CREEK
2 M W OF LANARK, Carroll, IL
Built 1982 Load: 32.4 t ADT: 200
E TELEGRAPH ROAD
FairOver: ROCK CREEK
1.5 M NE CHADWICK, Carroll, IL
Built 1984 Load: 32.4 t ADT: 250
SOUTH SHANNON ROUT
FairOver: MIDDLE CREEK
5 M NE MILLEDGEVILLE, Carroll, IL
Built 1986 Load: 32.4 t ADT: 500
SOUTH WATER ROAD
FairOver: ELKHORN CREEK
6 M NE MILLEDGEVILLE, Carroll, IL
Built 1978 Load: 32.4 t ADT: 50
E ELM ROAD
FairOver: ELKHORN CREEK
5 M NE MILLEDGEVILLE, Carroll, IL
Built 1983 Load: 32.4 t ADT: 25
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.