County profile · official public datasets

Perry County, IL

136 public highway bridges tracked in the FHWA National Bridge Inventory: 38.2% rated Good, 54.4% Fair, 7.4% Poor.

136
Public bridges: 38.2%
Good condition: 7.4%
Poor condition

The verdict

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

Perry County posts a better-than-median Poor-condition share among rated counties in the state across mid-size county bridge inventory.

Top 47%
lowest Poor share in state: 7.4%
Poor-condition share: 136
public highway bridges: 1981
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.

Perry County Bridge Snapshot

According to the Federal Highway Administration's 2024 National Bridge Inventory, Perry County ranks #48 of 102 Illinois counties with at least 5 public highway bridges on Poor-condition share (lower share ranks better; currently 7.4%). Perry County, Illinois contains 136 public highway bridges. Roughly 38.2% are rated “Good,” 54.4% “Fair,” and 7.4% “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

136

Public highway bridges in Perry County

Good condition

38.2%

52 of 136 rated 7-9

Fair condition

54.4%

74 of 136 rated 5-6

Poor condition

7.4%

10 of 136 rated 4 or below

In-state Poor-share rank

#48 of 102

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

Condition distribution

Share of 136 NBI-tracked bridges by lowest applicable component rating.

Good

38.2% (52)

Fair

54.4% (74)

Poor

7.4% (10)

Perry County's Poor-condition bridges carry 9,425 vehicle crossings a day

That is 9% of the county's reported daily bridge traffic on 7.4% of its bridges: Poor-condition structures carry more traffic than their share of the inventory. Each Poor bridge averages 943 crossings a day against 734 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 136 of 136 bridges in this county that report an average daily traffic count. Source: FHWA National Bridge Inventory, 2024 release.

18.4% of Perry County's bridges have passed the 50-year mark

25 of the 136 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 38.2% 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 61% of the county's Poor-condition bridge traffic

ILL 154 over BEAUCOUP CREEK, built 1962, carries 5,750 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 10-bridge count understates how much of the daily burden sits on a single crossing.

Share is of the 9,425 daily crossings on Poor-rated bridges that report a traffic count. Source: FHWA National Bridge Inventory, 2024 release.

1900s

9
1920s

5
1930s

1
1940s

1
1950s

7
1960s

2
1970s

12
1980s

40
1990s

25
2000s

18
2010s

13
2020s

3

What this shows Construction peaked in the 1980s, when 40 of the county's bridges still in the inventory were built, which is 29.4% of those with a recorded year. That cohort is now 35 to 44 years old in the 2024 inventory. Its average build year (1981) matches the Illinois average (1979).

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

The 5 Illinois counties nearest Perry County in number of bridges, with their condition splits. Its 7.4% Poor share is the 2nd-lowest of these 6. Its average build year of 1981 against a peer-group mean of 1984 is in line with the group.

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

Bridge inventory size and condition shares for Perry County and the 5 Illinois counties closest to it in inventory size
County	Bridges	Good	Fair	Poor	Avg. built
Randolph County	149	59.7%	32.9%	7.4%	1981
Henderson County	142	33.1%	54.9%	12%	1985
Perry County (this page)	136	38.2%	54.4%	7.4%	1981
Kendall County	132	52.3%	35.6%	12.1%	1990
Massac County	132	43.9%	47.7%	8.3%	1980
Monroe County	132	59.1%	34.1%	6.8%	1986

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

Similar inventory size

Nearest county inventories outside IL (136 bridges here).

Bullock County, AL · 136 bridges
Jackson County, AR · 136 bridges
Lincoln County, KY · 136 bridges
Morehouse County, LA · 136 bridges

Similar average build year

Nearest mean year-built outside IL (1981 here).

Franklin County, OH · avg 1981 · 922 bridges
Greenville County, SC · avg 1981 · 635 bridges
Montgomery County, OH · avg 1981 · 632 bridges
Shawnee County, KS · avg 1981 · 563 bridges

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

All 136 Good 52 Fair 74 Poor 10

Fair-condition bridges (74)

Sort:

Perry County Bridge Snapshot

Condition distribution

Perry County's Poor-condition bridges carry 9,425 vehicle crossings a day

18.4% of Perry County's bridges have passed the 50-year mark

One structure carries 61% of the county's Poor-condition bridge traffic

How Perry 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

Fair-condition bridges (74)

PYATT-CUTLER RD/CH

ILL 150

ILL 127

CO HWY 11

US 51

CH 3

TR 332

TR 305A

TR 268

TR146

TR 305

FAS 1880

CH 7

TR 55

TR 305A

TR 297B

TR 76

CO HWY 8

CO HWY 3

TR 109

TR 81

TR 42

TR 189

TR 84

TR 84

TR 153A

TR 91

TR 231

TOWNSHIP ROAD 197B

TR 233

TR 129

CH 22-TR1CO RD

TR 35

TR 109

TR 118A

CH 23

CO HWY 2

FAS 866-CH 11

TR 59

TR 283

TR 320

FAS 1881

CH 17

TR 233

TR241-SACREDHEART

TR 182C-CUDGETOWN

TR 67

TR 71

TR 71

TR 174 A

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