County profile · official public datasets

Hamilton County, IN

454 public highway bridges tracked in the FHWA National Bridge Inventory: 68.3% rated Good, 29.1% Fair, 2.6% Poor.

454
Public bridges: 68.3%
Good condition: 2.6%
Poor condition

The verdict

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

Hamilton County pairs a better-than-median Poor-condition share among rated counties in the state with a newer average build year than the state inventory.

Top 27%
lowest Poor share in state: 2.6%
Poor-condition share: 454
public highway bridges: 1996
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.

Hamilton County Bridge Snapshot

According to the Federal Highway Administration's 2024 National Bridge Inventory, Hamilton County ranks #25 of 92 Indiana counties with at least 5 public highway bridges on Poor-condition share (lower share ranks better; currently 2.6%). Hamilton County, Indiana contains 454 public highway bridges. Roughly 68.3% are rated “Good,” 29.1% “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

454

Public highway bridges in Hamilton County

Good condition

68.3%

310 of 454 rated 7-9

Fair condition

29.1%

132 of 454 rated 5-6

Poor condition

2.6%

12 of 454 rated 4 or below

In-state Poor-share rank

#25 of 92

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

Condition distribution

Share of 454 NBI-tracked bridges by lowest applicable component rating.

Good

68.3% (310)

Fair

29.1% (132)

Poor

2.6% (12)

Hamilton County's Poor-condition bridges carry 43,030 vehicle crossings a day

That is 0.8% 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 3,586 crossings a day against 12,679 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 453 of 454 bridges in this county that report an average daily traffic count. Source: FHWA National Bridge Inventory, 2024 release.

16.3% of Hamilton County's bridges have passed the 50-year mark

74 of the 454 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 68.3% 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 36.6% of the county's Poor-condition bridge traffic

LITTLE CHICAGO RD over MORSE RESERVOIR, built 1954, carries 15,750 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 12-bridge count understates how much of the daily burden sits on a single crossing.

Share is of the 43,030 daily crossings on Poor-rated bridges that report a traffic count. Source: FHWA National Bridge Inventory, 2024 release.

1910s

2
1920s

2
1930s

2
1940s

4
1950s

11
1960s

36
1970s

39
1980s

44
1990s

64
2000s

119
2010s

109
2020s

22

What this shows Construction peaked in the 2000s, when 119 of the county's bridges still in the inventory were built, which is 26.2% of those with a recorded year. That cohort is now 15 to 24 years old in the 2024 inventory. Its average build year is 1996, 18 years newer than the Indiana average of 1978.

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

The 5 Indiana counties nearest Hamilton County in number of bridges, with their condition splits. Its 2.6% Poor share is the 2nd-lowest of these 6. Its average build year of 1996 against a peer-group mean of 1980 is 16 years newer.

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

Bridge inventory size and condition shares for Hamilton County and the 5 Indiana counties closest to it in inventory size
County	Bridges	Good	Fair	Poor	Avg. built
Lake County	501	51.1%	42.9%	6%	1984
Hamilton County (this page)	454	68.3%	29.1%	2.6%	1996
Gibson County	362	42.8%	53%	4.1%	1978
Hendricks County	355	41.4%	56.3%	2.3%	1982
Wayne County	343	41.1%	54.8%	4.1%	1975
Tippecanoe County	330	55.2%	39.7%	5.2%	1982

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

Similar inventory size

Nearest county inventories outside IN (454 bridges here).

Forsyth County, NC · 454 bridges
Somerset County, PA · 454 bridges
Woodbury County, IA · 455 bridges
Hunt County, TX · 456 bridges

Similar average build year

Nearest mean year-built outside IN (1996 here).

Clark County, NV · avg 1996 · 1,141 bridges
Hays County, TX · avg 1996 · 272 bridges
Jackson County, MS · avg 1996 · 268 bridges
Douglas County, CO · avg 1996 · 263 bridges

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

All 454 Good 310 Fair 132 Poor 12

All bridges (454)

Sort:

Hamilton County Bridge Snapshot

Condition distribution

Hamilton County's Poor-condition bridges carry 43,030 vehicle crossings a day

16.3% of Hamilton County's bridges have passed the 50-year mark

One structure carries 36.6% of the county's Poor-condition bridge traffic

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

Nationwide counties with similar inventory size or average build year

Similar inventory size

Similar average build year

All bridges (454)

E MAIN ST

SR 38

RAMP US31S - I465

19TH ST

PENNINGTON RD

113TH ST EAST

US 31

SR 32

116TH ST EAST

EAST STREET

126TH ST EB/WB

RAMP I465W-US31N

SR 38

RULON RD

OLIO RD

STRAWTOWN AVE

MORGAN CREEK CT

106TH STREET WB

CUMBERLAND RD

ALLISONVILLE RD

WOLF RUN RD

JERKWATER RD

226TH ST WEST

SR 213

SR 32

111 TH STREET

241ST ST EAST

SR 38

126TH ST EAST

SR 431 NB

206TH STREET

JOLIET RD

SMOKY ROW ROAD

RAMP & FARM ROAD

SR 32

SPRINGSTONE RD

HAGUE RD

WESTFIELD BLVD

US 31

116TH ST EAST

I-69

SIX POINTS RD

CEDAR POINT DR

HAZELDELL PKWY

CHERRY TREE RD

ATLANTIC AVE

LITTLE CHICAGO RD

CYNTHEANNE RD

ATLANTIC RD

106TH ST EAST

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