County profile · official public datasets

Onslow County, NC

172 public highway bridges tracked in the FHWA National Bridge Inventory: 49.4% rated Good, 47.7% Fair, 2.9% Poor.

172
Public bridges: 49.4%
Good condition: 2.9%
Poor condition

The verdict

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

Onslow 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: 2.9%
Poor-condition share: 172
public highway bridges: 1995
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.

Onslow County Bridge Snapshot

According to the Federal Highway Administration's 2024 National Bridge Inventory, Onslow County ranks #27 of 100 North Carolina counties with at least 5 public highway bridges on Poor-condition share (lower share ranks better; currently 2.9%). Onslow County, North Carolina contains 172 public highway bridges. Roughly 49.4% are rated “Good,” 47.7% “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

172

Public highway bridges in Onslow County

Good condition

49.4%

85 of 172 rated 7-9

Fair condition

47.7%

82 of 172 rated 5-6

Poor condition

2.9%

5 of 172 rated 4 or below

In-state Poor-share rank

#27 of 100

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

Condition distribution

Share of 172 NBI-tracked bridges by lowest applicable component rating.

Good

49.4% (85)

Fair

47.7% (82)

Poor

2.9% (5)

Onslow County's Poor-condition bridges carry 51,830 vehicle crossings a day

That is 3.5% 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 10,366 crossings a day against 10,111 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 170 of 172 bridges in this county that report an average daily traffic count. Source: FHWA National Bridge Inventory, 2024 release.

14% of Onslow County's bridges have passed the 50-year mark

24 of the 172 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 49.4% 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 55% of the county's Poor-condition bridge traffic

US17 over CHANEY CREEK, built 1957, carries 28,500 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 5-bridge count understates how much of the daily burden sits on a single crossing.

Share is of the 51,830 daily crossings on Poor-rated bridges that report a traffic count. Source: FHWA National Bridge Inventory, 2024 release.

1920s

2
1940s

4
1950s

4
1960s

11
1970s

5
1980s

26
1990s

37
2000s

38
2010s

44
2020s

1

What this shows Construction peaked in the 2010s, when 44 of the county's bridges still in the inventory were built, which is 25.6% of those with a recorded year. That cohort is now 5 to 14 years old in the 2024 inventory. Its average build year is 1995, 9 years newer than the North Carolina average of 1986.

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

The 5 North Carolina counties nearest Onslow County in number of bridges, with their condition splits. Its 2.9% Poor share is the 2nd-lowest of these 6. Its average build year of 1995 against a peer-group mean of 1985 is 10 years newer.

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

Bridge inventory size and condition shares for Onslow County and the 5 North Carolina counties closest to it in inventory size
County	Bridges	Good	Fair	Poor	Avg. built
Moore County	178	48.9%	49.4%	1.7%	1981
Onslow County (this page)	172	49.4%	47.7%	2.9%	1995
Anson County	169	52.7%	43.2%	4.1%	1985
Lincoln County	169	45.6%	49.1%	5.3%	1984
Yadkin County	168	32.7%	57.7%	9.5%	1986
Brunswick County	166	39.2%	54.8%	6%	1991

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

Similar inventory size

Nearest county inventories outside NC (172 bridges here).

Colbert County, AL · 172 bridges
Marshall County, AL · 172 bridges
Moultrie County, IL · 172 bridges
Newton County, IN · 172 bridges

Similar average build year

Nearest mean year-built outside NC (1995 here).

Williamson County, TX · avg 1995 · 1,170 bridges
Craighead County, AR · avg 1995 · 442 bridges
Utah County, UT · avg 1995 · 271 bridges
DeSoto County, MS · avg 1995 · 266 bridges

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

All 172 Good 85 Fair 82 Poor 5

All bridges (172)

Sort:

Onslow County Bridge Snapshot

Condition distribution

Onslow County's Poor-condition bridges carry 51,830 vehicle crossings a day

14% of Onslow County's bridges have passed the 50-year mark

One structure carries 55% of the county's Poor-condition bridge traffic

How Onslow 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

All bridges (172)

US17 S

WILSON BLVD

WILSON BLVD

SR 1406

SR1406

WILSON BLVD. (NB)

SR1330

US17 NC24 NC53

WALLACE CREEK RD

NC50

SR1503

NC50

SR1557

US17N.

SR1331

US17S.BYP

US17N.BYP

SR1427

SR1332

SR1406

SR1434

SR1406

SR1316

WILSON BLVD

WILSON BLVD

NC24E NC53E

NC53

SR1308

SR1105

US17N

CC ROAD

WILSON BLVD

SR1423

US17S

US17S

BASE ENTRY RD

STONE BAY CONNECT

SR1518

FLORENCE ROAD

WILSON BLVD

SR2614

US17N.RAMP

US17S

NC 172

SR1225

US17 RAMP SBL

US17 RAMP NBL

US17S.RAMP

US17N

US17BUS NC24BUS

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