County profile · official public datasets

Franklin County, IL

310 public highway bridges tracked in the FHWA National Bridge Inventory: 77.1% rated Good, 20.3% Fair, 2.6% Poor.

310
Public bridges: 77.1%
Good condition: 2.6%
Poor condition

The verdict

According to the Federal Highway Administration's 2024 National Bridge Inventory.

Franklin County posts a top-5% lowest Poor-condition share among rated counties in the state across mid-size county bridge inventory.

Top 4%
lowest Poor share in state: 2.6%
Poor-condition share: 310
public highway bridges: 1983
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.

Franklin County Bridge Snapshot

According to the Federal Highway Administration's 2024 National Bridge Inventory, Franklin County ranks #4 of 102 Illinois counties with at least 5 public highway bridges on Poor-condition share (lower share ranks better; currently 2.6%). Franklin County, Illinois contains 310 public highway bridges. Roughly 77.1% are rated “Good,” 20.3% “Fair,” and 2.6% “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.

Total bridges

310

Public highway bridges in Franklin County

Good condition

77.1%

239 of 310 rated 7-9

Fair condition

20.3%

63 of 310 rated 5-6

Poor condition

2.6%

8 of 310 rated 4 or below

In-state Poor-share rank

#4 of 102

Among Illinois counties with 5+ bridges, lower share ranks better

Condition distribution

Share of 310 NBI-tracked bridges by lowest applicable component rating.

Good

77.1% (239)

Fair

20.3% (63)

Poor

2.6% (8)

Franklin County's Poor-condition bridges carry 12,275 vehicle crossings a day

That is 2.2% of the county's reported daily bridge traffic on 2.6% of its bridges: Poor-condition structures carry less traffic than their share of the inventory. Each Poor bridge averages 1,534 crossings a day against 906 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 309 of 310 bridges in this county that report an average daily traffic count. Source: FHWA National Bridge Inventory, 2024 release.

25.2% of Franklin County's bridges have passed the 50-year mark

78 of the 310 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 77.1% 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 21.6% of the county's Poor-condition bridge traffic

ILL 154 over REND LAKE, built 1966, carries 2,650 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 8-bridge count understates how much of the daily burden sits on a single crossing.

Share is of the 12,275 daily crossings on Poor-rated bridges that report a traffic count. Source: FHWA National Bridge Inventory, 2024 release.

1900s

12
1920s

13
1930s

5
1940s

2
1950s

8
1960s

34
1970s

22
1980s

60
1990s

66
2000s

56
2010s

23
2020s

9

What this shows Construction peaked in the 1990s, when 66 of the county's bridges still in the inventory were built, which is 21.3% of those with a recorded year. That cohort is now 25 to 34 years old in the 2024 inventory. Its average build year (1983) matches the Illinois average (1979).

How Franklin County compares with Illinois's closest counties by inventory size

The 5 Illinois counties nearest Franklin County in number of bridges, with their condition splits. Its 2.6% Poor share is the 1st-lowest of these 6. Its average build year of 1983 against a peer-group mean of 1978 is 5 years newer.

Showing the 5 closest of 101 Illinois counties eligible for comparison.

Bridge inventory size and condition shares for Franklin County and the 5 Illinois counties closest to it in inventory size
County	Bridges	Good	Fair	Poor	Avg. built
Christian County	321	16.2%	67%	16.8%	1969
Adams County	319	40.4%	53.6%	6%	1976
Franklin County (this page)	310	77.1%	20.3%	2.6%	1983
Coles County	304	39.5%	51.6%	8.9%	1981
Knox County	304	49.3%	39.5%	11.2%	1982
Ford County	302	55.6%	38.1%	6.3%	1983

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 Franklin 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 Franklin County, both outside Illinois so the neighborhoods are not the same-state size table above.

Similar inventory size

Nearest county inventories outside IL (310 bridges here).

Belmont County, OH · 310 bridges
Okmulgee County, OK · 310 bridges
Woods County, OK · 310 bridges
Tom Green County, TX · 310 bridges

Similar average build year

Nearest mean year-built outside IL (1983 here).

Dallas County, TX · avg 1983 · 3,230 bridges
Bexar County, TX · avg 1983 · 2,342 bridges
Sedgwick County, KS · avg 1983 · 1,333 bridges
Bernalillo County, NM · avg 1983 · 496 bridges

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

All 310 Good 239 Fair 63 Poor 8

Good-condition bridges (239)

Sort:

Franklin County Bridge Snapshot

Condition distribution

Franklin County's Poor-condition bridges carry 12,275 vehicle crossings a day

25.2% of Franklin County's bridges have passed the 50-year mark

One structure carries 21.6% of the county's Poor-condition bridge traffic

How Franklin County compares with Illinois's closest counties by inventory size

Nationwide counties with similar inventory size or average build year

Similar inventory size

Similar average build year

Good-condition bridges (239)

CH 7

TR 45

TR 112

TR 6

TR 68A

TR 3

TR 36

TR 204

TR 141

TR 119

FAS1877-YELLOWBANK

FAS 875

FAS 875

TR 311

TR 48

TR 362

TR 335

TR 164B

TR 92

TR 40

TR 204

TR 21

TR 110

TR 248A

TR 95

TR 278

TR 165

TR 149B

FAU 9459

TR 92

FAU 9459

TR 260

TR 93

TR 177

TR 34

TR 137

FAS 1972

TR 278

TR 388

CH 15

TR 335

TR 21

TR 388-EASTERN TWP

TR 204

TR 11

TR 157

TR 7

TR 84A

CH 12

TR 22

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