County profile · official public datasets

Hamilton County, OH

783 public highway bridges tracked in the FHWA National Bridge Inventory: 57.5% rated Good, 39.6% Fair, 2.9% Poor.

783
Public bridges: 57.5%
Good condition: 2.9%
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 an older average build year than the state inventory.

Top 43%
lowest Poor share in state: 2.9%
Poor-condition share: 783
public highway bridges: 1970
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 #38 of 88 Ohio counties with at least 5 public highway bridges on Poor-condition share (lower share ranks better; currently 2.9%). Hamilton County, Ohio contains 783 public highway bridges. Roughly 57.5% are rated “Good,” 39.6% “Fair,” and 2.9% “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

783

Public highway bridges in Hamilton County

Good condition

57.5%

450 of 783 rated 7-9

Fair condition

39.6%

310 of 783 rated 5-6

Poor condition

2.9%

23 of 783 rated 4 or below

In-state Poor-share rank

#38 of 88

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

Condition distribution

Share of 783 NBI-tracked bridges by lowest applicable component rating.

Good

57.5% (450)

Fair

39.6% (310)

Poor

2.9% (23)

Hamilton County's Poor-condition bridges carry 561,488 vehicle crossings a day

That is 3.3% of the county's reported daily bridge traffic on 2.9% of its bridges: Poor-condition structures carry more traffic than their share of the inventory. Each Poor bridge averages 24,413 crossings a day against 22,584 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 782 of 783 bridges in this county that report an average daily traffic count. Source: FHWA National Bridge Inventory, 2024 release.

60.2% of Hamilton County's bridges have passed the 50-year mark

471 of the 783 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 57.5% 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 16.3% of the county's Poor-condition bridge traffic

IR 75 over TRIBUTARY MILL CREEK, built 1960, carries 91,244 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 23-bridge count understates how much of the daily burden sits on a single crossing.

Share is of the 561,488 daily crossings on Poor-rated bridges that report a traffic count. Source: FHWA National Bridge Inventory, 2024 release.

pre-1900

3
1900s

18
1910s

25
1920s

28
1930s

29
1940s

14
1950s

51
1960s

178
1970s

193
1980s

48
1990s

94
2000s

59
2010s

33
2020s

10

What this shows Construction peaked in the 1970s, when 193 of the county's bridges still in the inventory were built, which is 24.6% of those with a recorded year. That cohort is now 45 to 54 years old in the 2024 inventory. Its average build year is 1970, 7 years older than the Ohio average of 1977.

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

The 5 Ohio counties nearest Hamilton County in number of bridges, with their condition splits. Its 2.9% Poor share is the 4th-lowest of these 6. Its average build year of 1970 against a peer-group mean of 1977 is 7 years older.

Showing the 5 closest of 87 Ohio counties eligible for comparison.

Bridge inventory size and condition shares for Hamilton County and the 5 Ohio counties closest to it in inventory size
County	Bridges	Good	Fair	Poor	Avg. built
Franklin County	922	72.2%	25.8%	2%	1981
Cuyahoga County	871	43.2%	47.2%	9.6%	1969
Hamilton County (this page)	783	57.5%	39.6%	2.9%	1970
Montgomery County	632	67.2%	30.1%	2.7%	1981
Summit County	563	55.4%	42.3%	2.3%	1974
Wood County	508	64.2%	31.5%	4.3%	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 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 Ohio so the neighborhoods are not the same-state size table above.

Similar inventory size

Nearest county inventories outside OH (783 bridges here).

Baltimore County, MD · 783 bridges
El Paso County, TX · 783 bridges
Johnson County, KS · 781 bridges
Fulton County, GA · 775 bridges

Similar average build year

Nearest mean year-built outside OH (1970 here).

Yavapai County, AZ · avg 1970 · 543 bridges
Garfield County, OK · avg 1970 · 504 bridges
San Luis Obispo County, CA · avg 1970 · 401 bridges
Somerset County, NJ · avg 1970 · 397 bridges

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

All 783 Good 450 Fair 310 Poor 23

Good-condition bridges (450)

Sort:

Hamilton County Bridge Snapshot

Condition distribution

Hamilton County's Poor-condition bridges carry 561,488 vehicle crossings a day

60.2% of Hamilton County's bridges have passed the 50-year mark

One structure carries 16.3% of the county's Poor-condition bridge traffic

How Hamilton County compares with Ohio'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 (450)

MUDDY CREEK ROAD

US 42

SR 126 WB

SB IR 75

McKinney Rd

EB Warsaw Rp (C716

US 50 RAMP F

US 50

NB IR 71

SB IR 71

NB IR 71

IR 75

I71 Rmp A frm NB71

WB RAMP-SB IR 75

WB IR 275

DOG TROT ROAD

ELLIOTT AVE.(AHT)

SEYMOUR AVENUE

WOOSTER ROAD

POWERS STREET

CUNNINGHAM DRIVE

SIDNEY ROAD

WYOMING AVENUE

REED HARTMAN HWY.

SR 126 WEST BOUND

RMP MCMILLAN-I71N

COMPTON ROAD

Joe Nuxhall

Bridle Road

CSI ACCESS DRIVE

SUSPENSION BRIDGE

Bank Road

PIPPIN ROAD

SB IR 71

I-71 NB

IR 74

INTERSTATE 74

North Bend RD C142

IR 75

GLENDALE-MILFORD

EB IR 275

SPRING GROVE AVE

KENNEDY AVENUE

EB IR 275

W. KEMPER ROAD

WINTON RD (CR 293)

EAGLE CREEK ROAD

RACE ROAD

Blue Rock Road

WILLEY ROAD

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