County profile · official public datasets

Johnston County, NC

318 public highway bridges tracked in the FHWA National Bridge Inventory: 42.1% rated Good, 53.5% Fair, 4.4% Poor.

318
Public bridges: 42.1%
Good condition: 4.4%
Poor condition

The verdict

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

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

Top 48%
lowest Poor share in state: 4.4%
Poor-condition share: 318
public highway bridges: 1989
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.

Johnston County Bridge Snapshot

According to the Federal Highway Administration's 2024 National Bridge Inventory, Johnston County ranks #48 of 100 North Carolina counties with at least 5 public highway bridges on Poor-condition share (lower share ranks better; currently 4.4%). Johnston County, North Carolina contains 318 public highway bridges. Roughly 42.1% are rated “Good,” 53.5% “Fair,” and 4.4% “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

318

Public highway bridges in Johnston County

Good condition

42.1%

134 of 318 rated 7-9

Fair condition

53.5%

170 of 318 rated 5-6

Poor condition

4.4%

14 of 318 rated 4 or below

In-state Poor-share rank

#48 of 100

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

Condition distribution

Share of 318 NBI-tracked bridges by lowest applicable component rating.

Good

42.1% (134)

Fair

53.5% (170)

Poor

4.4% (14)

Johnston County's Poor-condition bridges carry 109,390 vehicle crossings a day

That is 4.6% of the county's reported daily bridge traffic on 4.4% of its bridges: Poor-condition structures carry more traffic than their share of the inventory. Each Poor bridge averages 7,814 crossings a day against 6,795 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 318 of 318 bridges in this county that report an average daily traffic count. Source: FHWA National Bridge Inventory, 2024 release.

26.4% of Johnston County's bridges have passed the 50-year mark

84 of the 318 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 42.1% 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 20.8% of the county's Poor-condition bridge traffic

I95 SBL over BLACK CREEK, built 1955, carries 22,750 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 14-bridge count understates how much of the daily burden sits on a single crossing.

Share is of the 109,390 daily crossings on Poor-rated bridges that report a traffic count. Source: FHWA National Bridge Inventory, 2024 release.

1920s

4
1930s

3
1940s

4
1950s

31
1960s

32
1970s

20
1980s

60
1990s

55
2000s

45
2010s

45
2020s

19

What this shows Construction peaked in the 1980s, when 60 of the county's bridges still in the inventory were built, which is 18.9% of those with a recorded year. That cohort is now 35 to 44 years old in the 2024 inventory. Its average build year (1989) matches the North Carolina average (1986).

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

The 5 North Carolina counties nearest Johnston County in number of bridges, with their condition splits. Its 4.4% Poor share is the 3rd-lowest of these 6. Its average build year of 1989 against a peer-group mean of 1981 is 8 years newer.

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

Bridge inventory size and condition shares for Johnston County and the 5 North Carolina counties closest to it in inventory size
County	Bridges	Good	Fair	Poor	Avg. built
Davidson County	340	42.9%	52.9%	4.1%	1988
Iredell County	335	35.2%	54.6%	10.1%	1981
Johnston County (this page)	318	42.1%	53.5%	4.4%	1989
Durham County	314	35.7%	60.8%	3.5%	1984
Surry County	308	28.9%	62%	9.1%	1979
Rutherford County	298	40.3%	47.3%	12.4%	1974

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

Similar inventory size

Nearest county inventories outside NC (318 bridges here).

Garland County, AR · 319 bridges
Mesa County, CO · 319 bridges
Adams County, IL · 319 bridges
Bates County, MO · 319 bridges

Similar average build year

Nearest mean year-built outside NC (1989 here).

Harris County, TX · avg 1989 · 4,029 bridges
Buffalo County, NE · avg 1989 · 459 bridges
Brazos County, TX · avg 1989 · 370 bridges
Dubuque County, IA · avg 1989 · 346 bridges

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

All 318 Good 134 Fair 170 Poor 14

Fair-condition bridges (170)

Sort:

Johnston County Bridge Snapshot

Condition distribution

Johnston County's Poor-condition bridges carry 109,390 vehicle crossings a day

26.4% of Johnston County's bridges have passed the 50-year mark

One structure carries 20.8% of the county's Poor-condition bridge traffic

How Johnston 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

Fair-condition bridges (170)

SR1201

SR1201

SR1171

I95 SBL

SR1211

NC210

US70A

NC231

SR1517

US70W

SR1136

SR1507

SR1138

SR1560

SR1136

SR1122

SR1140

SR1331

NC96

NC96

I40

SR1162

I95N

SR1941

SR1227

US70RMP

SR1201

US701

SR1733

SR1735

SR1309

SR1176

US70W

US70E

US70

SR1722

US301

US70

SR1162

SR2363

US301

SR1714

SR1553

US70W.BUS

SR2310

SR1001

US70

SR2523

SR1147

SR1715

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