County profile · official public datasets

Harrison County, IN

127 public highway bridges tracked in the FHWA National Bridge Inventory: 37.8% rated Good, 59.8% Fair, 2.4% Poor.

127
Public bridges
37.8%
Good condition
2.4%
Poor condition

The verdict

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

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

Top 22%
lowest Poor share in state
2.4%
Poor-condition share
127
public highway bridges
1982
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.

Harrison County Bridge Snapshot

According to the Federal Highway Administration's 2024 National Bridge Inventory, Harrison County ranks #20 of 92 Indiana counties with at least 5 public highway bridges on Poor-condition share (lower share ranks better; currently 2.4%). Harrison County, Indiana contains 127 public highway bridges. Roughly 37.8% are rated “Good,” 59.8% “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

127

Public highway bridges in Harrison County

Good condition

37.8%

48 of 127 rated 7-9

Fair condition

59.8%

76 of 127 rated 5-6

Poor condition

2.4%

3 of 127 rated 4 or below

In-state Poor-share rank

#20 of 92

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

Condition distribution

Share of 127 NBI-tracked bridges by lowest applicable component rating.

Good
37.8% (48)
Fair
59.8% (76)
Poor
2.4% (3)

Harrison County's Poor-condition bridges carry 7,007 vehicle crossings a day

That is 2.3% of the county's reported daily bridge traffic on 2.4% of its bridges: Poor-condition structures carry less traffic than their share of the inventory. Each Poor bridge averages 2,336 crossings a day against 1,454 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 127 of 127 bridges in this county that report an average daily traffic count. Source: FHWA National Bridge Inventory, 2024 release.

37% of Harrison County's bridges have passed the 50-year mark

47 of the 127 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 37.8% 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 86.9% of the county's Poor-condition bridge traffic

OLD SR 337 over LITTLE INDIAN CREEK, built 1984, carries 6,087 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 7,007 daily crossings on Poor-rated bridges that report a traffic count. Source: FHWA National Bridge Inventory, 2024 release.

When Harrison County's bridges were built

127 bridges with a recorded construction year, grouped by decade

bridges

What this shows Construction peaked in the 1990s, when 29 of the county's bridges still in the inventory were built, which is 22.8% of those with a recorded year. That cohort is now 25 to 34 years old in the 2024 inventory. Its average build year (1982) matches the Indiana average (1978).

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

How Harrison County compares with Indiana's closest counties by inventory size

The 5 Indiana counties nearest Harrison County in number of bridges, with their condition splits. Its 2.4% Poor share is the 2nd-lowest of these 6. Its average build year of 1982 against a peer-group mean of 1972 is 10 years newer.

Showing the 5 closest of 91 Indiana counties eligible for comparison.

Bridge inventory size and condition shares for Harrison County and the 5 Indiana counties closest to it in inventory size
County Bridges Poor
Steuben County 135 2.2%
Warren County 135 6.7%
Vermillion County 127 7.9%
Harrison County (this page) 127 2.4%
Crawford County 123 17.1%
Scott County 118 5.9%

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

Similar inventory size

Nearest county inventories outside IN (127 bridges here).

Similar average build year

Nearest mean year-built outside IN (1982 here).

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

Poor-condition bridges (3)

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.