County profile · official public datasets

Polk County, NC

127 public highway bridges tracked in the FHWA National Bridge Inventory: 35.4% rated Good, 53.5% Fair, 11% Poor.

127
Public bridges: 35.4%
Good condition: 11%
Poor condition

The verdict

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

Polk 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.

84th
of 100 on Poor share: 11%
Poor-condition share: 127
public highway bridges: 1978
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.

Polk County Bridge Snapshot

According to the Federal Highway Administration's 2024 National Bridge Inventory, Polk County ranks #84 of 100 North Carolina counties with at least 5 public highway bridges on Poor-condition share (lower share ranks better; currently 11%). Polk County, North Carolina contains 127 public highway bridges. Roughly 35.4% are rated “Good,” 53.5% “Fair,” and 11% “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

127

Public highway bridges in Polk County

Good condition

35.4%

45 of 127 rated 7-9

Fair condition

53.5%

68 of 127 rated 5-6

Poor condition

11%

14 of 127 rated 4 or below

In-state Poor-share rank

#84 of 100

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

Condition distribution

Share of 127 NBI-tracked bridges by lowest applicable component rating.

Good

35.4% (45)

Fair

53.5% (68)

Poor

11% (14)

Polk County's Poor-condition bridges carry 10,590 vehicle crossings a day

That is 2.4% of the county's reported daily bridge traffic on 11% of its bridges: Poor-condition structures carry less traffic than their share of the inventory. Each Poor bridge averages 756 crossings a day against 2,236 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 127 of 127 bridges in this county that report an average daily traffic count. Source: FHWA National Bridge Inventory, 2024 release.

48.8% of Polk County's bridges have passed the 50-year mark

62 of the 127 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 35.4% 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 27.4% of the county's Poor-condition bridge traffic

NC9 over S.BR.LITTLE WHITE OAK CR, built 1967, carries 2,900 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 10,590 daily crossings on Poor-rated bridges that report a traffic count. Source: FHWA National Bridge Inventory, 2024 release.

1920s

4
1930s

4
1940s

1
1950s

9
1960s

38
1970s

18
1980s

14
1990s

16
2000s

5
2010s

15
2020s

3

What this shows Construction peaked in the 1960s, when 38 of the county's bridges still in the inventory were built, which is 29.9% of those with a recorded year. That cohort is now 55 to 64 years old in the 2024 inventory. Its average build year is 1978, 8 years older than the North Carolina average of 1986.

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

The 5 North Carolina counties nearest Polk County in number of bridges, with their condition splits. Its 11% Poor share is the 4th-lowest of these 6. Its average build year of 1978 against a peer-group mean of 1986 is 8 years older.

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

Bridge inventory size and condition shares for Polk County and the 5 North Carolina counties closest to it in inventory size
County	Bridges	Good	Fair	Poor	Avg. built
Swain County	129	25.6%	62.8%	11.6%	1973
Mitchell County	127	35.4%	39.4%	25.2%	1981
Polk County (this page)	127	35.4%	53.5%	11%	1978
Martin County	124	45.2%	51.6%	3.2%	1988
Bladen County	123	64.2%	34.1%	1.6%	1992
New Hanover County	123	65%	31.7%	3.3%	1995

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

Similar inventory size

Nearest county inventories outside NC (127 bridges here).

Yuba County, CA · 127 bridges
Jefferson County, ID · 127 bridges
Harrison County, IN · 127 bridges
Vermillion County, IN · 127 bridges

Similar average build year

Nearest mean year-built outside NC (1978 here).

Orange County, CA · avg 1978 · 1,164 bridges
Sumner County, KS · avg 1978 · 659 bridges
Allen County, IN · avg 1978 · 613 bridges
Livingston County, IL · avg 1978 · 579 bridges

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

All 127 Good 45 Fair 68 Poor 14

All bridges (127)

Sort:

Polk County Bridge Snapshot

Condition distribution

Polk County's Poor-condition bridges carry 10,590 vehicle crossings a day

48.8% of Polk County's bridges have passed the 50-year mark

One structure carries 27.4% of the county's Poor-condition bridge traffic

How Polk 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 (127)

SR1322

SR1315

SR1324

SR1340

SR1124

SR1331

SR1547

SR1005

SR1005

SR1337

SR1341

NC108

SR1506

US176

US176

NC108

US176

SR1188

SR1135

SR1501

SR1162

NC108

SR1339

SR1183

NC9

SR1526

SR1501

SR1311

SR1179

SR1519

SR1155

SR1135

I-26

NC108

SR1525

I-26

US74 RAMPS

NC9

SR1516

I26 RAMP

SR1513

I-26 WBL

US74 EBL

I-26 EBL

SR1302

SR1326

SR1138

US74 WBL

SR1345

US74 EBL

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