Total bridges
165
Public highway bridges in Hamilton County
County profile · official public datasets
Hamilton County, IL
165 public highway bridges tracked in the FHWA National Bridge Inventory: 80% rated Good, 17.6% Fair, 2.4% Poor.
- 165
- Public bridges
- 80%
- Good condition
- 2.4%
- Poor condition
The verdict
According to the Federal Highway Administration's 2024 National Bridge Inventory.
Hamilton County pairs a top-5% lowest Poor-condition share among rated counties in the state with a newer average build year than the state inventory.
- Top 2%
- lowest Poor share in state
- 2.4%
- Poor-condition share
- 165
- public highway bridges
- 1989
- 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.
Hamilton County Bridge Snapshot
According to the Federal Highway Administration's 2024 National Bridge Inventory, Hamilton County ranks #2 of 102 Illinois counties with at least 5 public highway bridges on Poor-condition share (lower share ranks better; currently 2.4%). Hamilton County, Illinois contains 165 public highway bridges. Roughly 80% are rated “Good,” 17.6% “Fair,” and 2.4% “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
80%
132 of 165 rated 7-9
Fair condition
17.6%
29 of 165 rated 5-6
Poor condition
2.4%
4 of 165 rated 4 or below
In-state Poor-share rank
#2 of 102
Among Illinois counties with 5+ bridges, lower share ranks better
Condition distribution
Share of 165 NBI-tracked bridges by lowest applicable component rating.
Good 80% (132)
Fair 17.6% (29)
Poor 2.4% (4)
Hamilton County's Poor-condition bridges carry 3,400 vehicle crossings a day
That is 3.6% of the county's reported daily bridge traffic on 2.4% of its bridges: Poor-condition structures carry more traffic than their share of the inventory. Each Poor bridge averages 850 crossings a day against 387 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 165 of 165 bridges in this county that report an average daily traffic count. Source: FHWA National Bridge Inventory, 2024 release.
12.1% of Hamilton County's bridges have passed the 50-year mark
20 of the 165 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 80% 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 94.1% of the county's Poor-condition bridge traffic
FAP-853 (ILL-14) over BEAR CREEK, built 1923, carries 3,200 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 4-bridge count understates how much of the daily burden sits on a single crossing.
Share is of the 3,400 daily crossings on Poor-rated bridges that report a traffic count. Source: FHWA National Bridge Inventory, 2024 release.
When Hamilton County's bridges were built
165 bridges with a recorded construction year, grouped by decade
- 1900s 3
1900–1909
3 bridges
- 1920s 6
1920–1929
6 bridges
- 1930s 1
1930–1939
1 bridges
- 1940s 1
1940–1949
1 bridges
- 1950s 2
1950–1959
2 bridges
- 1960s 3
1960–1969
3 bridges
- 1970s 13
1970–1979
13 bridges
- 1980s
1980–1989
44 bridges
- 1990s
1990–1999
42 bridges
- 2000s
2000–2009
32 bridges
- 2010s
2010–2019
18 bridges
What this shows Construction peaked in the 1980s, when 44 of the county's bridges still in the inventory were built, which is 26.7% of those with a recorded year. That cohort is now 35 to 44 years old in the 2024 inventory. Its average build year is 1989, 10 years newer than the Illinois average of 1979.
How Hamilton County compares with Illinois's closest counties by inventory size
The 5 Illinois counties nearest Hamilton County in number of bridges, with their condition splits. Its 2.4% Poor share is the 1st-lowest of these 6. Its average build year of 1989 against a peer-group mean of 1979 is 10 years newer.
Showing the 5 closest of 101 Illinois counties eligible for comparison.
| County | Bridges | Good | Fair | Poor | Avg. built |
|---|---|---|---|---|---|
| Cumberland County | 169 | 54.4% | 39.1% | 6.5% | 1979 |
| Clay County | 166 | 49.4% | 37.3% | 13.3% | 1982 |
| Hamilton County (this page) | 165 | 80% | 17.6% | 2.4% | 1989 |
| Mercer County | 163 | 50.9% | 42.3% | 6.7% | 1982 |
| Bond County | 162 | 45.7% | 46.3% | 8% | 1971 |
| Greene County | 162 | 51.9% | 42.6% | 5.6% | 1981 |
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 Hamilton 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 Hamilton County, both outside Illinois so the neighborhoods are not the same-state size table above.
Similar inventory size
Nearest county inventories outside IL (165 bridges here).
- Cleburne County, AL · 165 bridges
- Randolph County, AL · 165 bridges
- Plumas County, CA · 165 bridges
- Leon County, FL · 165 bridges
Similar average build year
Nearest mean year-built outside IL (1989 here).
- Harris County, TX · avg 1989 · 4,029 bridges
- Mecklenburg County, NC · avg 1989 · 746 bridges
- Buffalo County, NE · avg 1989 · 459 bridges
- Brazos County, TX · avg 1989 · 370 bridges
Source: FHWA National Bridge Inventory, 2024 release. Peers floor at 10 bridges so stub inventories cannot own the match.
Fair-condition bridges (29)
TR-356
FairOver: SWAN POND LATERAL
2 MI NE DALE, Hamilton, IL
Built 1909 Load: 18.5 t ADT: 25
FAS-1879 (CH-7)
FairOver: TRIB BIG CREEK
1 MI S DAHLGREN, Hamilton, IL
Built 1962 Load: 19.4 t ADT: 650
FAS-1879
FairOver: MIDDLE FORK CREEK
1.3 MI NE MACEDONIA, Hamilton, IL
Built 1960 Load: 21.1 t ADT: 300
TR-107
FairOver: BIG CREEK
6.8 MI S WAYNE CO LN, Hamilton, IL
Built 1941 Load: 23.3 t ADT: 10
FAS-882
FairOver: FERGUSON CREEK
1.75 MI W BLAIRSVILL, Hamilton, IL
Built 1936 Load: 24.3 t ADT: 1,350
FAS-881
FairOver: TRIB BROUGHTON LAT
1.25 MI W BROUGHTON, Hamilton, IL
Built 1962 Load: 24.3 t ADT: 375
FAP-849 (ILL-142)
FairOver: STREAM
3.1 MI SE JEFF CO LN, Hamilton, IL
Built 1929 Load: 27.2 t ADT: 2,350
TR-210
FairOver: RECTOR CREEK
1.25 MI SW WALPOLE, Hamilton, IL
Built 1979 Load: 29.8 t ADT: 25
TR-178
FairOver: SHELTON CREEK DRAIN
2.5 MI NW BELLE PRAI, Hamilton, IL
Built 1978 Load: 30.8 t ADT: 25
FAP-849 (ILL-142)
FairOver: STREAM
6.9 MI SE JEFF CO LN, Hamilton, IL
Built 1929 Load: 32.4 t ADT: 2,700
TR-301
FairOver: WHEELER CREEK
3 MI SW DOLAN LAKE, Hamilton, IL
Built 1977 Load: 32.4 t ADT: 50
TR-369
FairOver: WHEELER CREEK
3.3 MI E DALE, Hamilton, IL
Built 1983 Load: 32.4 t ADT: 25
TR-176
FairOver: BIG CREEK
0.5 MI NE DELAFIELD, Hamilton, IL
Built 1982 Load: 32.4 t ADT: 100
FAP-853 (ILL-14)
FairOver: BR 10 MILE CREEK
5.2 MI E FRANK CO LN, Hamilton, IL
Built 1979 Load: 33.4 t ADT: 2,100
FAP-855 (ILL-14)
FairOver: LAKEY CREEK
1.5 MI E ILL-142, Hamilton, IL
Built 1923 Load: 33.7 t ADT: 3,200
CH-14 (FAS-883)
FairOver: N FK SALINE RIVER
1 MI W FEAKEYVILLE, Hamilton, IL
Built 1985 Load: 33.7 t ADT: 1,000
FAP-853 (ILL-14)
FairOver: SULLIVAN BRANCH
.8 MI E FRANK CO LN, Hamilton, IL
Built 1985 Load: 35.0 t ADT: 2,100
TR-273
FairOver: TEN MILE CREEK
3 MI SE MCLEANSBORO, Hamilton, IL
Built 1983 Load: 35.0 t ADT: 75
FAP-849 (ILL-142)
FairOver: BIG CREEK
6.1 MI SE JEFF CO LN, Hamilton, IL
Built 1990 Load: 35.3 t ADT: 2,350
FAP 776/IL 242
FairOver: STREAM
5.5 MI S WAYNE CO LI, Hamilton, IL
Built 2002 Load: 35.6 t ADT: 1,250
FAP-849 (ILL-142)
FairOver: BLUE CREEK
5.3 MI S JEFFERSN CL, Hamilton, IL
Built 1990 Load: 36.9 t ADT: 2,350
FAP-776 (ILL-142)
FairOver: BR LAKEY CREEK
3.7 MI S ILL-14, Hamilton, IL
Built 1984 Load: 37.9 t ADT: 2,400
FAP-776 (ILL-142)
FairOver: BEAR CREEK
1.8 MI S ILL-14, Hamilton, IL
Built 1928 Load: 39.2 t ADT: 2,550
FAP-849 (ILL-142)
FairOver: MIDDLE CREEK
6.5 MI SE JEFF CO LN, Hamilton, IL
Built 1929 Load: 42.4 t ADT: 2,700
FAP-849 (ILL-142)
FairOver: OPOSSUM CREEK
9.9 MI SE JEFF CO LN, Hamilton, IL
Built 1996 Load: 42.8 t ADT: 2,700
FAP-776 (ILL-242)
FairOver: SHELTON CREEK
1.4 MI S WAYNE CO LN, Hamilton, IL
Built 2010 Load: 42.8 t ADT: 1,250
TR-357
FairOver: CONTRARY CREEK
3.75 MI WNW DALE, Hamilton, IL
Built 1973 Load: 46.3 t ADT: 25
FAP-855 (ILL-14)
FairOver: WHEELER CREEK
4 MI E ILL-142, Hamilton, IL
Built 1953 Load: 48.3 t ADT: 2,100
FAP 776 (ILL-142)
FairOver: TEN MILE CREEK
2.3 MI S ILL 14, Hamilton, IL
Built 1997 Load: 48.9 t ADT: 2,550
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.