Total bridges
281
Public highway bridges in Logan County
County profile · official public datasets
Logan County, OH
281 public highway bridges tracked in the FHWA National Bridge Inventory: 78.3% rated Good, 20.6% Fair, 1.1% Poor.
- 281
- Public bridges
- 78.3%
- Good condition
- 1.1%
- Poor condition
The verdict
According to the Federal Highway Administration's 2024 National Bridge Inventory.
Logan County posts a top-quartile lowest Poor-condition share among rated counties in the state across mid-size county bridge inventory.
- Top 11%
- lowest Poor share in state
- 1.1%
- Poor-condition share
- 281
- public highway bridges
- 1979
- 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.
Logan County Bridge Snapshot
According to the Federal Highway Administration's 2024 National Bridge Inventory, Logan County ranks #10 of 88 Ohio counties with at least 5 public highway bridges on Poor-condition share (lower share ranks better; currently 1.1%). Logan County, Ohio contains 281 public highway bridges. Roughly 78.3% are rated “Good,” 20.6% “Fair,” and 1.1% “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
78.3%
220 of 281 rated 7-9
Fair condition
20.6%
58 of 281 rated 5-6
Poor condition
1.1%
3 of 281 rated 4 or below
In-state Poor-share rank
#10 of 88
Among Ohio counties with 5+ bridges, lower share ranks better
Condition distribution
Share of 281 NBI-tracked bridges by lowest applicable component rating.
Good 78.3% (220)
Fair 20.6% (58)
Poor 1.1% (3)
Logan County's Poor-condition bridges carry 1,172 vehicle crossings a day
That is 0.2% of the county's reported daily bridge traffic on 1.1% of its bridges: Poor-condition structures carry less traffic than their share of the inventory. Each Poor bridge averages 391 crossings a day against 1,608 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 281 of 281 bridges in this county that report an average daily traffic count. Source: FHWA National Bridge Inventory, 2024 release.
39.1% of Logan County's bridges have passed the 50-year mark
110 of the 281 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 78.3% 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 69.6% of the county's Poor-condition bridge traffic
CR 21B over MIAMI RIVER, built 1882, carries 816 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 3-bridge count understates how much of the daily burden sits on a single crossing.
Share is of the 1,172 daily crossings on Poor-rated bridges that report a traffic count. Source: FHWA National Bridge Inventory, 2024 release.
When Logan County's bridges were built
281 bridges with a recorded construction year, grouped by decade
- pre-1900 2
Built before 1900
2 bridges
- 1900s 14
1900–1909
14 bridges
- 1910s 4
1910–1919
4 bridges
- 1920s 1
1920–1929
1 bridges
- 1930s 7
1930–1939
7 bridges
- 1940s 5
1940–1949
5 bridges
- 1950s 8
1950–1959
8 bridges
- 1960s
1960–1969
59 bridges
- 1970s 22
1970–1979
22 bridges
- 1980s 20
1980–1989
20 bridges
- 1990s
1990–1999
60 bridges
- 2000s
2000–2009
60 bridges
- 2010s 15
2010–2019
15 bridges
- 2020s 4
2020–2029
4 bridges
What this shows Construction peaked in the 1990s, when 60 of the county's bridges still in the inventory were built, which is 21.4% of those with a recorded year. That cohort is now 25 to 34 years old in the 2024 inventory. Its average build year (1979) matches the Ohio average (1977).
How Logan County compares with Ohio's closest counties by inventory size
The 5 Ohio counties nearest Logan County in number of bridges, with their condition splits. Its 1.1% Poor share is the 1st-lowest of these 6. Its average build year of 1979 against a peer-group mean of 1982 is in line with the group.
Showing the 5 closest of 87 Ohio counties eligible for comparison.
| County | Bridges | Good | Fair | Poor | Avg. built |
|---|---|---|---|---|---|
| Ashland County | 283 | 65% | 32.5% | 2.5% | 1980 |
| Logan County (this page) | 281 | 78.3% | 20.6% | 1.1% | 1979 |
| Shelby County | 277 | 74% | 23.5% | 2.5% | 1989 |
| Hardin County | 276 | 64.1% | 28.6% | 7.2% | 1979 |
| Seneca County | 275 | 72.7% | 25.8% | 1.5% | 1983 |
| Knox County | 274 | 54.4% | 40.1% | 5.5% | 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 Logan 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 Logan County, both outside Ohio so the neighborhoods are not the same-state size table above.
Similar inventory size
Nearest county inventories outside OH (281 bridges here).
- Smith County, KS · 281 bridges
- Daviess County, KY · 282 bridges
- Acadia County, LA · 282 bridges
- New Madrid County, MO · 282 bridges
Similar average build year
Nearest mean year-built outside OH (1979 here).
- Pima County, AZ · avg 1979 · 1,150 bridges
- Jefferson County, KY · avg 1979 · 662 bridges
- Spartanburg County, SC · avg 1979 · 638 bridges
- McPherson County, KS · avg 1979 · 586 bridges
Source: FHWA National Bridge Inventory, 2024 release. Peers floor at 10 bridges so stub inventories cannot own the match.
Poor-condition bridges (3)
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.