County profile · official public datasets

Niagara County, NY

268 public highway bridges tracked in the FHWA National Bridge Inventory: 41.8% rated Good, 50.7% Fair, 7.5% Poor.

268
Public bridges: 41.8%
Good condition: 7.5%
Poor condition

The verdict

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

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

Top 29%
lowest Poor share in state: 7.5%
Poor-condition share: 268
public highway bridges: 1974
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.

Niagara County Bridge Snapshot

According to the Federal Highway Administration's 2024 National Bridge Inventory, Niagara County ranks #18 of 62 New York counties with at least 5 public highway bridges on Poor-condition share (lower share ranks better; currently 7.5%). Niagara County, New York contains 268 public highway bridges. Roughly 41.8% are rated “Good,” 50.7% “Fair,” and 7.5% “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

268

Public highway bridges in Niagara County

Good condition

41.8%

112 of 268 rated 7-9

Fair condition

50.7%

136 of 268 rated 5-6

Poor condition

7.5%

20 of 268 rated 4 or below

In-state Poor-share rank

#18 of 62

Among New York counties with 5+ bridges, lower share ranks better

Condition distribution

Share of 268 NBI-tracked bridges by lowest applicable component rating.

Good

41.8% (112)

Fair

50.7% (136)

Poor

7.5% (20)

Niagara County's Poor-condition bridges carry 30,255 vehicle crossings a day

That is 2.3% of the county's reported daily bridge traffic on 7.1% of its bridges: Poor-condition structures carry less traffic than their share of the inventory. Each Poor bridge averages 1,592 crossings a day against 4,827 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 266 of 268 bridges in this county that report an average daily traffic count. Source: FHWA National Bridge Inventory, 2024 release.

56.7% of Niagara County's bridges have passed the 50-year mark

152 of the 268 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 41.8% 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 25.4% of the county's Poor-condition bridge traffic

MAIN STREET over ERIE CANAL, built 1912, carries 7,684 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 20-bridge count understates how much of the daily burden sits on a single crossing.

Share is of the 30,255 daily crossings on Poor-rated bridges that report a traffic count. Source: FHWA National Bridge Inventory, 2024 release.

pre-1900

1
1900s

4
1910s

9
1920s

1
1930s

11
1940s

14
1950s

25
1960s

76
1970s

16
1980s

24
1990s

31
2000s

26
2010s

22
2020s

8

What this shows Construction peaked in the 1960s, when 76 of the county's bridges still in the inventory were built, which is 28.4% of those with a recorded year. That cohort is now 55 to 64 years old in the 2024 inventory. Its average build year (1974) matches the New York average (1972).

How Niagara County compares with New York's closest counties by inventory size

The 5 New York counties nearest Niagara County in number of bridges, with their condition splits. Its 7.5% Poor share is the 3rd-lowest of these 6. Its average build year of 1974 against a peer-group mean of 1975 is in line with the group.

Showing the 5 closest of 61 New York counties eligible for comparison.

Bridge inventory size and condition shares for Niagara County and the 5 New York counties closest to it in inventory size
County	Bridges	Good	Fair	Poor	Avg. built
Rensselaer County	269	27.9%	57.2%	14.9%	1971
Niagara County (this page)	268	41.8%	50.7%	7.5%	1974
Otsego County	266	37.2%	55.3%	7.5%	1969
Chemung County	256	38.7%	54.7%	6.6%	1977
Chenango County	256	39.1%	53.1%	7.8%	1975
Essex County	256	48.4%	44.5%	7%	1981

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 Niagara 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 Niagara County, both outside New York so the neighborhoods are not the same-state size table above.

Similar inventory size

Nearest county inventories outside NY (268 bridges here).

Polk County, MN · 268 bridges
Jackson County, MS · 268 bridges
Warren County, NJ · 268 bridges
Delaware County, OH · 268 bridges

Similar average build year

Nearest mean year-built outside NY (1974 here).

Knox County, TN · avg 1974 · 588 bridges
Summit County, OH · avg 1974 · 563 bridges
Pierce County, WA · avg 1974 · 472 bridges
Lincoln County, OK · avg 1974 · 450 bridges

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

All 268 Good 112 Fair 136 Poor 20

Poor-condition bridges (20)

Sort:

Niagara County Bridge Snapshot

Condition distribution

Niagara County's Poor-condition bridges carry 30,255 vehicle crossings a day

56.7% of Niagara County's bridges have passed the 50-year mark

One structure carries 25.4% of the county's Poor-condition bridge traffic

How Niagara County compares with New York's closest counties by inventory size

Nationwide counties with similar inventory size or average build year

Similar inventory size

Similar average build year

Poor-condition bridges (20)

HUNT STREET

NORTH ADAM STREET

MAINLAND GREEN IS

GOAT IS-GREEN IS

HARTLAND ROAD

PLAZA DRIVE

SLAYTON SETTMT RD

HARTLAND ROAD

RTE 93

AIKEN ROAD

RTE 104

EAST AVENUE

ROYALTON CTR ROAD

THORNWOODS DRIVE

RTE 77

MAIN STREET

TOWNLINE ROAD

RTE 957A

RTE 957A

RTE 957A

Related