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.

Total bridges

165

Public highway bridges in Hamilton County

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

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.

Source FHWA National Bridge Inventory (year built) As of 2024 NBI release

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.

Bridge inventory size and condition shares for Hamilton County and the 5 Illinois counties closest to it in inventory size
County Bridges Poor
Cumberland County 169 6.5%
Clay County 166 13.3%
Hamilton County (this page) 165 2.4%
Mercer County 163 6.7%
Bond County 162 8%
Greene County 162 5.6%

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).

Similar average build year

Nearest mean year-built outside IL (1989 here).

Source: FHWA National Bridge Inventory, 2024 release. Peers floor at 10 bridges so stub inventories cannot own the match.

All bridges (165)

TR-421

Good

Over: DRAINAGE DITCH CREEK

2 MI N BROUGHTON, Hamilton, IL

Built 1985 Load: 32.4 t ADT: 25

TR-191

Good

Over: SULLIVAN BRANCH

3.5 NE MACEDONIA, Hamilton, IL

Built 1984 Load: 32.4 t ADT: 50

TR-482

Good

Over: TRIB LOST BRANCH

3 MI N DOLAN LAKE, Hamilton, IL

Built 1983 Load: 32.4 t ADT: 10

CH-9

Good

Over: BIG CREEK

0.75 MI N DELAFIELD, Hamilton, IL

Built 1986 Load: 32.4 t ADT: 700

TR-438

Good

Over: LICK CREEK

1.25 MI SW DOLAN LK, Hamilton, IL

Built 1986 Load: 32.4 t ADT: 25

TR-205

Good

Over: TRIB BEAR CREEK

W EDGE MCLEANSBORO, Hamilton, IL

Built 1983 Load: 32.4 t ADT: 550

TR-90

Good

Over: HOGG CREEK

8 MI WSW DALE, Hamilton, IL

Built 1987 Load: 32.4 t ADT: 10

TR-99

Good

Over: TRIB BIG CREEK

2 MI NE DELAFIELD, Hamilton, IL

Built 1987 Load: 32.4 t ADT: 75

TR-57

Good

Over: SHELTON CREEK

1 MI NE DAHLGREN, Hamilton, IL

Built 1987 Load: 32.4 t ADT: 75

TR-448

Good

Over: LOST CREEK

0.5 MI S FEAKEYVILLE, Hamilton, IL

Built 1987 Load: 32.4 t ADT: 25

TR-248

Good

Over: BEAR CREEK

0.3 MI S MCLEANSBORO, Hamilton, IL

Built 1985 Load: 32.4 t ADT: 550

TR-238

Good

Over: HOGG CREEK

3.25 MI SW DALE, Hamilton, IL

Built 1988 Load: 32.4 t ADT: 25

TR 482

Good

Over: TRIB LOST CREEK DRAI

2 MI N DOLAN LAKE, Hamilton, IL

Built 1990 Load: 32.4 t ADT: 10

FAS-882 (CH-10)

Good

Over: RADARS BRANCH

0.25 MI NE BUNGAY, Hamilton, IL

Built 1987 Load: 32.4 t ADT: 1,200

FAS-2878 (CH-6)

Good

Over: TEN MILE CREEK

3 MI SW MCLEANSBORO, Hamilton, IL

Built 1989 Load: 32.4 t ADT: 750

FAS-873

Good

Over: GREASY CREEK

7 MI W DALE, Hamilton, IL

Built 1991 Load: 32.4 t ADT: 225

TR-178

Good

Over: AUXIER CREEK

3 MI NW BELLE PRAIRI, Hamilton, IL

Built 1989 Load: 32.4 t ADT: 25

CH-1

Good

Over: BEVER CREEK

1.5 MI S BUNGAY, Hamilton, IL

Built 1989 Load: 32.4 t ADT: 175

FAS-881 (CH-11)

Good

Over: N FK SALINE RIVER

2 MI E BROUGHTON, Hamilton, IL

Built 1989 Load: 32.4 t ADT: 100

TR-1

Good

Over: N FORK SALINE RIVER

3 MI W CORNERVILLE, Hamilton, IL

Built 1997 Load: 32.4 t ADT: 100

TR-1 (SALINE CO)

Good

Over: MIDDLE FORK CREEK

3.75 MI W CORNERVILL, Hamilton, IL

Built 1989 Load: 32.4 t ADT: 100

CH-19

Good

Over: TRIB BIG CREEK

3.5 MI N MCLEANSBORO, Hamilton, IL

Built 1991 Load: 32.4 t ADT: 200

TR-312

Good

Over: TEN MILE CREEK

3 MI SE MCLEANSBORO, Hamilton, IL

Built 1990 Load: 32.4 t ADT: 25

TR-470

Good

Over: CREEK

3.5 MI S BUNGAY, Hamilton, IL

Built 1994 Load: 32.4 t ADT: 10

TR-349

Good

Over: NORTH FORK

2.2 MI NE DALE, Hamilton, IL

Built 1991 Load: 32.4 t ADT: 25

TR-95

Good

Over: MIDDLE CREEK

1 MI SW DEALFIELD, Hamilton, IL

Built 1993 Load: 32.4 t ADT: 75

TR-141

Good

Over: OPPOSUM CREEK

1.65 MI SE DELAFIELD, Hamilton, IL

Built 1992 Load: 32.4 t ADT: 75

FAS-2878

Good

Over: CONTRARY CREEK

6 MI SW MCLEANSBORO, Hamilton, IL

Built 1993 Load: 32.4 t ADT: 250

TR-236

Good

Over: SHELTON CREEK DRAIN

0.75 MI N BELLE PRAI, Hamilton, IL

Built 1993 Load: 32.4 t ADT: 50

TR-382

Good

Over: POND CREEK DRAIN

1.5 MI N BROUGHTON, Hamilton, IL

Built 1993 Load: 32.4 t ADT: 25

CH-19

Good

Over: TRIB OPPOSUM CREEK

3.25 MI NW MCLEANSBO, Hamilton, IL

Built 1994 Load: 32.4 t ADT: 100

TR-297A

Good

Over: TRIB BIG MUDDY

2 MI SE MACEDONIA, Hamilton, IL

Built 1995 Load: 32.4 t ADT: 25

TR-184

Good

Over: CONTRARY CREEK

5 MI SW MCLEANSBORO, Hamilton, IL

Built 1996 Load: 32.4 t ADT: 25

TR-349

Good

Over: WHEELER CREEK

3 MI NE DALE, Hamilton, IL

Built 2004 Load: 32.4 t ADT: 25

TR 199

Good

Over: WHEELER CREEK

3 MI NE MCLEANSBORO, Hamilton, IL

Built 1995 Load: 32.4 t ADT: 25

CH 2

Good

Over: TRIB YOUNG BRANCH

3.75 MI E BROUGHTON, Hamilton, IL

Built 1998 Load: 32.4 t ADT: 25

TR 121

Good

Over: FERGUSON CREEK

1.5 MI SW BLAIRSVILL, Hamilton, IL

Built 1997 Load: 32.4 t ADT: 75

TR 296A

Good

Over: TRIB BIG CRK

3.2 MI NE MCLEANSBOR, Hamilton, IL

Built 1997 Load: 32.4 t ADT: 25

TR 114

Good

Over: HOGG CREEK

7.5 MI SW DALE, Hamilton, IL

Built 1998 Load: 32.4 t ADT: 10

FAS 879

Good

Over: HOGG CREEK

6 MI SW DALE, Hamilton, IL

Built 1997 Load: 32.4 t ADT: 175

TR 237

Good

Over: BEAR CREEK

1.5 MI S MCLEANSBORO, Hamilton, IL

Built 1998 Load: 32.4 t ADT: 100

TR 45

Good

Over: ROCKY BRANCH

2.25 MI NW DALGREN, Hamilton, IL

Built 1999 Load: 32.4 t ADT: 75

TR 0135

Good

Over: TRIB BEAVER CR

3 MI SE BUNGAY, Hamilton, IL

Built 1998 Load: 32.4 t ADT: 25

FAS 1879

Good

Over: TRIB SULLIVAN BRANCH

8 MI S DAHLGREN, Hamilton, IL

Built 1999 Load: 32.4 t ADT: 650

FAS 878

Good

Over: HAW CREEK

3 MI E ADEN, Hamilton, IL

Built 1999 Load: 32.4 t ADT: 100

FAS 1879 (CH 17)

Good

Over: SULLIVAN CREEK

5 MI S DAHLGREN, Hamilton, IL

Built 2000 Load: 32.4 t ADT: 650

TR 181A

Good

Over: SULLIVAN BRANCH

6 MI S DAHLGREN, Hamilton, IL

Built 2000 Load: 32.4 t ADT: 25

CH 13

Good

Over: TRIB HOGG CREEK

8 MI SW DALE, Hamilton, IL

Built 2000 Load: 32.4 t ADT: 50

TR 290

Good

Over: CONTRARY CREEK

1.75 MI WSW DALE, Hamilton, IL

Built 2003 Load: 32.4 t ADT: 100

FAS 1898

Good

Over: LICK CREEK

4 MI N FEAKEYVILLE, Hamilton, IL

Built 2002 Load: 32.4 t ADT: 175
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.