County profile · official public datasets

Hardin County, IL

61 public highway bridges tracked in the FHWA National Bridge Inventory: 57.4% rated Good, 36.1% Fair, 6.6% Poor.

61
Public bridges: 57.4%
Good condition: 6.6%
Poor condition

The verdict

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

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

Top 36%
lowest Poor share in state: 6.6%
Poor-condition share: 61
public highway bridges: 1976
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.

Hardin County Bridge Snapshot

According to the Federal Highway Administration's 2024 National Bridge Inventory, Hardin County ranks #37 of 102 Illinois counties with at least 5 public highway bridges on Poor-condition share (lower share ranks better; currently 6.6%). Hardin County, Illinois contains 61 public highway bridges. Roughly 57.4% are rated “Good,” 36.1% “Fair,” and 6.6% “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

Public highway bridges in Hardin County

Good condition

57.4%

35 of 61 rated 7-9

Fair condition

36.1%

22 of 61 rated 5-6

Poor condition

6.6%

4 of 61 rated 4 or below

In-state Poor-share rank

#37 of 102

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

Condition distribution

Share of 61 NBI-tracked bridges by lowest applicable component rating.

Good

57.4% (35)

Fair

36.1% (22)

Poor

6.6% (4)

Hardin County's Poor-condition bridges carry 1,635 vehicle crossings a day

That is 6.8% of the county's reported daily bridge traffic on 6.6% of its bridges: Poor-condition structures carry more traffic than their share of the inventory. Each Poor bridge averages 409 crossings a day against 314 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 61 of 61 bridges in this county that report an average daily traffic count. Source: FHWA National Bridge Inventory, 2024 release.

41% of Hardin County's bridges have passed the 50-year mark

25 of the 61 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 57.4% 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 91.7% of the county's Poor-condition bridge traffic

ILL 146 over HOSICK CREEK, built 1953, carries 1,500 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 1,635 daily crossings on Poor-rated bridges that report a traffic count. Source: FHWA National Bridge Inventory, 2024 release.

1900s

1
1920s

5
1930s

2
1940s

1
1950s

9
1960s

5
1970s

8
1980s

8
1990s

8
2000s

7
2010s

7

What this shows Construction peaked in the 1950s, when 9 of the county's bridges still in the inventory were built, which is 14.8% of those with a recorded year. That cohort is now 65 to 74 years old in the 2024 inventory. Its average build year (1976) matches the Illinois average (1979).

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

The 5 Illinois counties nearest Hardin County in number of bridges, with their condition splits. Its 6.6% Poor share is the 2nd-lowest of these 6. Its average build year of 1976 against a peer-group mean of 1981 is 5 years older.

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

Bridge inventory size and condition shares for Hardin County and the 5 Illinois counties closest to it in inventory size
County	Bridges	Good	Fair	Poor	Avg. built
Calhoun County	81	53.1%	43.2%	3.7%	1983
Edwards County	79	64.6%	27.8%	7.6%	1982
Cass County	77	29.9%	50.6%	19.5%	1986
Brown County	71	47.9%	38%	14.1%	1975
Hardin County (this page)	61	57.4%	36.1%	6.6%	1976
Putnam County	50	26%	64%	10%	1980

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

Similar inventory size

Nearest county inventories outside IL (61 bridges here).

Amador County, CA · 61 bridges
Cheyenne County, CO · 61 bridges
Montezuma County, CO · 61 bridges
Atkinson County, GA · 61 bridges

Similar average build year

Nearest mean year-built outside IL (1976 here).

Marion County, IN · avg 1976 · 958 bridges
Mohave County, AZ · avg 1976 · 641 bridges
Comanche County, OK · avg 1976 · 593 bridges
Prince George's County, MD · avg 1976 · 576 bridges

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

All 61 Good 35 Fair 22 Poor 4

Good-condition bridges (35)

Sort:

Hardin County Bridge Snapshot

Condition distribution

Hardin County's Poor-condition bridges carry 1,635 vehicle crossings a day

41% of Hardin County's bridges have passed the 50-year mark

One structure carries 91.7% of the county's Poor-condition bridge traffic

How Hardin 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 (35)

TR6

FAS 2934

FAS 2934

FAS 1934

TR 5A SEC 26G

TR 31

TR 97

CH 12

TR 5A

FAS 2934

TR99

TR 39

TR 67

TR 81

TR 105

TR 5A

TR 101

TR 28

TR 67

TR 74

TR 39

TR 38

TR 79

TR 81

TR 97

7010 E

FAS 1934

ILL 146

ILL 146

FAP 782 ILL 1

EDMONSON LANDING

BASSET SCHOOL RD

ILL. 34

IL 1

ILL 146

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