County profile · official public datasets

Carroll County, TN

240 public highway bridges tracked in the FHWA National Bridge Inventory: 37.9% rated Good, 60% Fair, 2.1% Poor.

240
Public bridges: 37.9%
Good condition: 2.1%
Poor condition

The verdict

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

Carroll County pairs a top-quartile lowest Poor-condition share among rated counties in the state with a newer average build year than the state inventory.

Top 19%
lowest Poor share in state: 2.1%
Poor-condition share: 240
public highway bridges: 1982
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.

Carroll County Bridge Snapshot

According to the Federal Highway Administration's 2024 National Bridge Inventory, Carroll County ranks #18 of 95 Tennessee counties with at least 5 public highway bridges on Poor-condition share (lower share ranks better; currently 2.1%). Carroll County, Tennessee contains 240 public highway bridges. Roughly 37.9% are rated “Good,” 60% “Fair,” and 2.1% “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

240

Public highway bridges in Carroll County

Good condition

37.9%

91 of 240 rated 7-9

Fair condition

60%

144 of 240 rated 5-6

Poor condition

2.1%

5 of 240 rated 4 or below

In-state Poor-share rank

#18 of 95

Among Tennessee counties with 5+ bridges, lower share ranks better

Condition distribution

Share of 240 NBI-tracked bridges by lowest applicable component rating.

Good

37.9% (91)

Fair

60% (144)

Poor

2.1% (5)

Carroll County's Poor-condition bridges carry 1,694 vehicle crossings a day

That is 0.4% of the county's reported daily bridge traffic on 2.1% of its bridges: Poor-condition structures carry less traffic than their share of the inventory. Each Poor bridge averages 339 crossings a day against 1,273 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 240 of 240 bridges in this county that report an average daily traffic count. Source: FHWA National Bridge Inventory, 2024 release.

30.4% of Carroll County's bridges have passed the 50-year mark

73 of the 240 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 37.9% 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 50.2% of the county's Poor-condition bridge traffic

NFA A258 over SPRING CREEK, built 1960, carries 850 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 1,694 daily crossings on Poor-rated bridges that report a traffic count. Source: FHWA National Bridge Inventory, 2024 release.

1920s

17
1940s

1
1950s

29
1960s

14
1970s

17
1980s

68
1990s

46
2000s

20
2010s

26
2020s

2

What this shows Construction peaked in the 1980s, when 68 of the county's bridges still in the inventory were built, which is 28.3% of those with a recorded year. That cohort is now 35 to 44 years old in the 2024 inventory. Its average build year is 1982, 5 years newer than the Tennessee average of 1977.

How Carroll County compares with Tennessee's closest counties by inventory size

The 5 Tennessee counties nearest Carroll County in number of bridges, with their condition splits. Its 2.1% Poor share is the 2nd-lowest of these 6. Its average build year of 1982 against a peer-group mean of 1975 is 7 years newer.

Showing the 5 closest of 94 Tennessee counties eligible for comparison.

Bridge inventory size and condition shares for Carroll County and the 5 Tennessee counties closest to it in inventory size
County	Bridges	Good	Fair	Poor	Avg. built
Humphreys County	250	24.4%	68%	7.6%	1978
Dickson County	243	58.8%	35.8%	5.3%	1975
Haywood County	241	35.3%	60.2%	4.6%	1976
Marshall County	240	56.3%	43.8%	0%	1968
Carroll County (this page)	240	37.9%	60%	2.1%	1982
Dyer County	232	29.7%	62.1%	8.2%	1979

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 Carroll 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 Carroll County, both outside Tennessee so the neighborhoods are not the same-state size table above.

Similar inventory size

Nearest county inventories outside TN (240 bridges here).

Jefferson Davis County, LA · 240 bridges
St. Louis city County, MO · 240 bridges
Sheboygan County, WI · 240 bridges
Sumter County, AL · 241 bridges

Similar average build year

Nearest mean year-built outside TN (1982 here).

Oklahoma County, OK · avg 1982 · 1,216 bridges
Jackson County, MO · avg 1982 · 930 bridges
Milwaukee County, WI · avg 1982 · 893 bridges
Champaign County, IL · avg 1982 · 727 bridges

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

All 240 Good 91 Fair 144 Poor 5

Good-condition bridges (91)

Sort:

Carroll County Bridge Snapshot

Condition distribution

Carroll County's Poor-condition bridges carry 1,694 vehicle crossings a day

30.4% of Carroll County's bridges have passed the 50-year mark

One structure carries 50.2% of the county's Poor-condition bridge traffic

How Carroll County compares with Tennessee'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 (91)

NFA A708

NFA A724

NFA A729

FAS 424

FAS 424

FAS 424

FAS 424

FAS 424

FAS 424

FAS 424

FAS 424

FAS 423

FAS 424

NFA 1756

FAS 436

FAP 1

FAP 22 NB

FAP 22 SB

FAP 22

FAP 76

FAP 76

FAP 76

FAP 76

FAP 77

FAP 77

FAP 77

FAS 104

FAS 104

FAS 105

FAS 105

FAS 436

FAS 436

NFA A708

FAS 220

FAS 436

FAS 436

FAS 436

FAS 436

NFA 1720 (SA 0905)

FAS 22

FAS 220

Related