County profile · official public datasets

Unicoi County, TN

161 public highway bridges tracked in the FHWA National Bridge Inventory: 46% rated Good, 49.1% Fair, 5% Poor.

161
Public bridges
46%
Good condition
5%
Poor condition

The verdict

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

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

68th
of 95 on Poor share
5%
Poor-condition share
161
public highway bridges
1984
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.

Unicoi County Bridge Snapshot

According to the Federal Highway Administration's 2024 National Bridge Inventory, Unicoi County ranks #68 of 95 Tennessee counties with at least 5 public highway bridges on Poor-condition share (lower share ranks better; currently 5%). Unicoi County, Tennessee contains 161 public highway bridges. Roughly 46% are rated “Good,” 49.1% “Fair,” and 5% “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

161

Public highway bridges in Unicoi County

Good condition

46%

74 of 161 rated 7-9

Fair condition

49.1%

79 of 161 rated 5-6

Poor condition

5%

8 of 161 rated 4 or below

In-state Poor-share rank

#68 of 95

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

Condition distribution

Share of 161 NBI-tracked bridges by lowest applicable component rating.

Good
46% (74)
Fair
49.1% (79)
Poor
5% (8)

Unicoi County's Poor-condition bridges carry 5,009 vehicle crossings a day

That is 0.7% of the county's reported daily bridge traffic on 5% of its bridges: Poor-condition structures carry less traffic than their share of the inventory. Each Poor bridge averages 626 crossings a day against 4,878 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 161 of 161 bridges in this county that report an average daily traffic count. Source: FHWA National Bridge Inventory, 2024 release.

15.5% of Unicoi County's bridges have passed the 50-year mark

25 of the 161 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 46% 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 83% of the county's Poor-condition bridge traffic

FAS 107 over INDIAN CREEK, built 1928, carries 4,155 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 8-bridge count understates how much of the daily burden sits on a single crossing.

Share is of the 5,009 daily crossings on Poor-rated bridges that report a traffic count. Source: FHWA National Bridge Inventory, 2024 release.

When Unicoi County's bridges were built

161 bridges with a recorded construction year, grouped by decade

bridges

What this shows Construction peaked in the 1990s, when 51 of the county's bridges still in the inventory were built, which is 31.7% of those with a recorded year. That cohort is now 25 to 34 years old in the 2024 inventory. Its average build year is 1984, 7 years newer than the Tennessee average of 1977.

Source FHWA National Bridge Inventory (year built) As of 2024 NBI release

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

The 5 Tennessee counties nearest Unicoi County in number of bridges, with their condition splits. Its 5% Poor share is the 5th-lowest of these 6. Its average build year of 1984 against a peer-group mean of 1977 is 7 years newer.

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

Bridge inventory size and condition shares for Unicoi County and the 5 Tennessee counties closest to it in inventory size
County Bridges Poor
Crockett County 167 0.6%
Unicoi County (this page) 161 5%
Warren County 160 3.8%
Cannon County 159 10.7%
Roane County 159 1.9%
Franklin County 157 3.8%

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

Similar inventory size

Nearest county inventories outside TN (161 bridges here).

Similar average build year

Nearest mean year-built outside TN (1984 here).

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

Good-condition bridges (74)

NFA A604

Good

Over: SPIVEY CREEK

3MI OF ERNESTVILLE, Unicoi, TN

Built 2007 Load: 9.1 t ADT: 10

NFA A605

Good

Over: SPIVEY CREEK

3 MI S OF ERNESTVILLE, Unicoi, TN

Built 2007 Load: 15.3 t ADT: 10

NFA A058

Good

Over: SOUTH INDIAN CREEK

S OF ERWIN - W OF SR 36, Unicoi, TN

Built 1975 Load: 18.1 t ADT: 550

NFSR 25

Good

Over: LONGARM BRANCH

LONGARM BRANCH, Unicoi, TN

Built 2012 Load: 21.1 t ADT: 20

NFA B124

Good

Over: DEVIL FORK CREEK

3MI W OF I26, Unicoi, TN

Built 2009 Load: 24.3 t ADT: 10

NFSR 25

Good

Over: CLARKS CREEK

1.55 MI TO TN 107, Unicoi, TN

Built 2004 Load: 24.3 t ADT: 10

NFA 2557 (SA 8601)

Good

Over: RICE CREEK

JUST SW OF FLAG POND, Unicoi, TN

Built 1960 Load: 28.8 t ADT: 215

NFA 1419 (SA 8604)

Good

Over: I26

JUST N. OF ERWIN LIMITS, Unicoi, TN

Built 1981 Load: 29.2 t ADT: 6,383

I26 RT LN

Good

Over: NFA A369 (GARLAND RD)

1.3 M S OF CARTER CO LINE, Unicoi, TN

Built 1985 Load: 29.5 t ADT: 15,784

I26 LT LN

Good

Over: NFA A369 (GARLAND RD)

1.3 M S OF CARTER CO LINE, Unicoi, TN

Built 1985 Load: 29.5 t ADT: 15,784

I26 RT LN

Good

Over: NFA A370 (CASTILLE RD)

.5 M S OF CARTER CO LINE, Unicoi, TN

Built 1985 Load: 29.8 t ADT: 15,784

I26

Good

Over: 1347-UPPER HIGGINS CR.RD

4.61 MI FROM NC/TN ST LN, Unicoi, TN

Built 1995 Load: 31.4 t ADT: 8,759

NFA 1415

Good

Over: HONEYCOMB CREEK

JUST S OF CARTER CO LINE, Unicoi, TN

Built 1965 Load: 32.4 t ADT: 1,347

FAU 4703

Good

Over: MARTIN CREEK

CITY OF ERWIN, Unicoi, TN

Built 1999 Load: 32.4 t ADT: 1,868

NFA 4718

Good

Over: BRANCH

BTWN OLD & NEW SR36-ERWIN, Unicoi, TN

Built 1976 Load: 32.4 t ADT: 488

NFA 2624

Good

Over: BUFFALO CREEK

N OF UNICOI NEAR SR 36, Unicoi, TN

Built 2003 Load: 32.4 t ADT: 516

NFA A014

Good

Over: RICE CREEK

NEAR FLAG POND, Unicoi, TN

Built 1984 Load: 32.4 t ADT: 100

NFA A028

Good

Over: BIG BALD CREEK

2.8 M S OF SR36-SR81 JCT, Unicoi, TN

Built 1995 Load: 32.4 t ADT: 40

NFA A030

Good

Over: SOUTH INDIAN CREEK

JUST OFF SR 81 NEAR 36, Unicoi, TN

Built 1982 Load: 32.4 t ADT: 70

NFA A053

Good

Over: LITTLE BALD CREEK

S. OF SR 36, Unicoi, TN

Built 1983 Load: 32.4 t ADT: 160

NFA A055

Good

Over: LITTLE HIGGINS CREEK

NEAR SR 36-N OF ERNESTVL., Unicoi, TN

Built 2010 Load: 32.4 t ADT: 300

NFA A062

Good

Over: SOUTH INDIAN CREEK

S OF ERWIN, Unicoi, TN

Built 1987 Load: 32.4 t ADT: 130

NFA A069 (SA 8611)

Good

Over: SOUTH INDIAN CREEK

SW OF ERWIN, Unicoi, TN

Built 2011 Load: 32.4 t ADT: 360

NFA A100

Good

Over: MARTIN CREEK

IN ERWIN, Unicoi, TN

Built 1994 Load: 32.4 t ADT: 220

NFA A114

Good

Over: MARTIN CREEK

JUST SE OF ERWIN CITY LMT, Unicoi, TN

Built 1991 Load: 32.4 t ADT: 490

NFA A277

Good

Over: ROCK CREEK

N OFF SR395, Unicoi, TN

Built 1992 Load: 32.4 t ADT: 90

NFA A289

Good

Over: NORTH INDIAN CREEK

N. OF ERWIN, Unicoi, TN

Built 1981 Load: 32.4 t ADT: 370

NFA A300

Good

Over: NORTH INDIAN CREEK

N OF ERWIN NEAR SR 36, Unicoi, TN

Built 1982 Load: 32.4 t ADT: 320

NFA A305

Good

Over: NORTH INDIAN CREEK

W OF SR36-S OF UNICOI, Unicoi, TN

Built 1996 Load: 32.4 t ADT: 10

NFA A309

Good

Over: NORTH INDIAN CREEK

NEAR UNICOI W. OF SR 36, Unicoi, TN

Built 1995 Load: 32.4 t ADT: 130

NFA A387

Good

Over: SIMMERCY CREEK

JUST N OF SR107-SR173 JCT, Unicoi, TN

Built 1991 Load: 32.4 t ADT: 270

NFA A398

Good

Over: NORTH INDIAN CREEK

.48 MI FROM SR 107, Unicoi, TN

Built 1992 Load: 32.4 t ADT: 110

NFA A405

Good

Over: SOUTH INDIAN CREEK

NEAR JCT OF SR 36 & SR81, Unicoi, TN

Built 1986 Load: 32.4 t ADT: 50

NFA A304

Good

Over: NORTH INDIAN CREEK

W OF SR36-S OF UNICOI, Unicoi, TN

Built 1984 Load: 32.4 t ADT: 70

NFA A455

Good

Over: MARTINS CREEK

IN THE CITY OF ERWIN, Unicoi, TN

Built 1998 Load: 32.4 t ADT: 250

NFA A455

Good

Over: MARTINS CREEK

IN THE CITY OF ERWIN, Unicoi, TN

Built 1998 Load: 32.4 t ADT: 250

NFA A481

Good

Over: DRY CREEK

.1 MI NW OF DRY CREEK RD, Unicoi, TN

Built 2021 Load: 32.4 t ADT: 10

NFA A482

Good

Over: N INDIAN CREEK

.01 M N OF SR 107, Unicoi, TN

Built 2000 Load: 32.4 t ADT: 90

NFA A484

Good

Over: SOUTH INDIAN CREEK

LAVRN HILL RD, Unicoi, TN

Built 2000 Load: 32.4 t ADT: 10

NFA A507

Good

Over: DEVIL FORK CREEK

1MI OF SR 352, Unicoi, TN

Built 2009 Load: 32.4 t ADT: 10

NFA A038

Good

Over: SOUTH INDIAN CREEK

E OF SR81-.5 M N OF ROCKY, Unicoi, TN

Built 1987 Load: 32.4 t ADT: 10

NFA A609

Good

Over: SOUTH INDIAN CREEK

E OFF SR81 N OF SR352 JCT, Unicoi, TN

Built 1998 Load: 32.4 t ADT: 20

NFA 1347 (SA 8602)

Good

Over: HIGGINS CREEK

1.8 M S OF SR36, Unicoi, TN

Built 1980 Load: 32.4 t ADT: 234

I26 RT LN

Good

Over: CSX RAILROAD

2.3 M S OF CARTER CO LINE, Unicoi, TN

Built 1985 Load: 32.4 t ADT: 15,784

I26 LT LN

Good

Over: CSX RAILROAD

2.3 M S OF CARTER CO LINE, Unicoi, TN

Built 1985 Load: 32.4 t ADT: 15,784

I26 RT LN

Good

Over: NFA A357 (MC CLAUGIN RD)

.9 M N OF SR 173 JCT, Unicoi, TN

Built 1985 Load: 32.4 t ADT: 15,784

I26 LT LN

Good

Over: NFA A357 (MC CLAUGIN RD)

.9 M N OF SR 173 JCT, Unicoi, TN

Built 1985 Load: 32.4 t ADT: 15,784

I26 RT LN

Good

Over: NFA A305 (TINKER RD)

1.9 M S OF SR 173 JCT, Unicoi, TN

Built 1985 Load: 32.4 t ADT: 16,623

I26 LT LN

Good

Over: NFA A305 (TINKER RD)

1.9 M S OF SR 173 JCT, Unicoi, TN

Built 1985 Load: 32.4 t ADT: 16,623

I26 RT LN

Good

Over: NFA A300-PIPPEN HOLLOW R

JUST N OF ERWIN, Unicoi, TN

Built 1983 Load: 32.4 t ADT: 16,623
Data sourced from official public datasets. See our methodology for details. Retrieved and formatted by PlainBridges

Every figure on PlainBridges is rendered directly from federal source data, no number is typed in by an editor. This page draws directly on federal source data, no figure is typed in by an editor. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error. NBI condition categories reflect the latest reported inventory record, not a live safety, closure, or travel decision.