County profile · official public datasets

Iredell County, NC

335 public highway bridges tracked in the FHWA National Bridge Inventory: 35.2% rated Good, 54.6% Fair, 10.1% Poor.

335
Public bridges: 35.2%
Good condition: 10.1%
Poor condition

The verdict

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

Iredell County pairs a higher-than-median Poor-condition share among rated counties in the state with an older average build year than the state inventory.

81st
of 100 on Poor share: 10.1%
Poor-condition share: 335
public highway bridges: 1981
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.

Iredell County Bridge Snapshot

According to the Federal Highway Administration's 2024 National Bridge Inventory, Iredell County ranks #81 of 100 North Carolina counties with at least 5 public highway bridges on Poor-condition share (lower share ranks better; currently 10.1%). Iredell County, North Carolina contains 335 public highway bridges. Roughly 35.2% are rated “Good,” 54.6% “Fair,” and 10.1% “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.

Total bridges

335

Public highway bridges in Iredell County

Good condition

35.2%

118 of 335 rated 7-9

Fair condition

54.6%

183 of 335 rated 5-6

Poor condition

10.1%

34 of 335 rated 4 or below

In-state Poor-share rank

#81 of 100

Among North Carolina counties with 5+ bridges, lower share ranks better

Condition distribution

Share of 335 NBI-tracked bridges by lowest applicable component rating.

Good

35.2% (118)

Fair

54.6% (183)

Poor

10.1% (34)

Iredell County's Poor-condition bridges carry 158,650 vehicle crossings a day

That is 5.8% of the county's reported daily bridge traffic on 10.1% of its bridges: Poor-condition structures carry less traffic than their share of the inventory. Each Poor bridge averages 4,666 crossings a day against 7,233 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 335 of 335 bridges in this county that report an average daily traffic count. Source: FHWA National Bridge Inventory, 2024 release.

50.7% of Iredell County's bridges have passed the 50-year mark

170 of the 335 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 35.2% 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 19.4% of the county's Poor-condition bridge traffic

I-77 SBL over THIRD CREEK, built 1964, carries 30,750 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 34-bridge count understates how much of the daily burden sits on a single crossing.

Share is of the 158,650 daily crossings on Poor-rated bridges that report a traffic count. Source: FHWA National Bridge Inventory, 2024 release.

1920s

4
1940s

6
1950s

52
1960s

85
1970s

42
1980s

25
1990s

34
2000s

20
2010s

44
2020s

23

What this shows Construction peaked in the 1960s, when 85 of the county's bridges still in the inventory were built, which is 25.4% of those with a recorded year. That cohort is now 55 to 64 years old in the 2024 inventory. Its average build year is 1981, 5 years older than the North Carolina average of 1986.

How Iredell County compares with North Carolina's closest counties by inventory size

The 5 North Carolina counties nearest Iredell County in number of bridges, with their condition splits. Its 10.1% Poor share is the 5th-lowest of these 6. Its average build year of 1981 against a peer-group mean of 1989 is 8 years older.

Showing the 5 closest of 99 North Carolina counties eligible for comparison.

Bridge inventory size and condition shares for Iredell County and the 5 North Carolina counties closest to it in inventory size
County	Bridges	Good	Fair	Poor	Avg. built
Union County	353	46.5%	49.3%	4.2%	1991
Wilkes County	349	32.1%	53.3%	14.6%	1983
Cumberland County	348	67.2%	31.9%	0.9%	1992
Davidson County	340	42.9%	52.9%	4.1%	1988
Iredell County (this page)	335	35.2%	54.6%	10.1%	1981
Johnston County	318	42.1%	53.5%	4.4%	1989

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 Iredell 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 Iredell County, both outside North Carolina so the neighborhoods are not the same-state size table above.

Similar inventory size

Nearest county inventories outside NC (335 bridges here).

Shelby County, IL · 335 bridges
Washington County, KS · 335 bridges
Grand Forks County, ND · 335 bridges
Jefferson County, AR · 336 bridges

Similar average build year

Nearest mean year-built outside NC (1981 here).

Franklin County, OH · avg 1981 · 922 bridges
Greenville County, SC · avg 1981 · 635 bridges
Montgomery County, OH · avg 1981 · 632 bridges
McLean County, IL · avg 1981 · 624 bridges

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

All 335 Good 118 Fair 183 Poor 34

Good-condition bridges (118)

Sort:

Iredell County Bridge Snapshot

Condition distribution

Iredell County's Poor-condition bridges carry 158,650 vehicle crossings a day

50.7% of Iredell County's bridges have passed the 50-year mark

One structure carries 19.4% of the county's Poor-condition bridge traffic

How Iredell County compares with North Carolina'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 (118)

SR1590

SR2155

SR1100

STATE PARK

NC115

NC115

SR1565

NC115

US64

US21

SR1550

SR1147

I40 WBL

SR1852

SR1813

SR2158

SR2379

SR1322

SR2617

SR1151

SR1907

I77 SBL

SR1832

SR2308

SR2163

SR2136

US70

SR2322

SR1337

SR1803

SR1843

SR1577

SR1862

SR1807

SR2115

SR1421

SR1614

SR1302

SR1595

SR1892

SR1828

SR1004

SR1585

SR2103

I40

SR3089

SR2359

NC115

SR1817

SR2168

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