County profile · official public datasets

Decatur County, TN

104 public highway bridges tracked in the FHWA National Bridge Inventory: 35.6% rated Good, 63.5% Fair, 1% Poor.

104
Public bridges: 35.6%
Good condition: 1%
Poor condition

The verdict

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

Decatur County pairs a top-10% lowest Poor-condition share among rated counties in the state with a newer average build year than the state inventory.

Top 6%
lowest Poor share in state: 1%
Poor-condition share: 104
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.

Decatur County Bridge Snapshot

According to the Federal Highway Administration's 2024 National Bridge Inventory, Decatur County ranks #6 of 95 Tennessee counties with at least 5 public highway bridges on Poor-condition share (lower share ranks better; currently 1%). Decatur County, Tennessee contains 104 public highway bridges. Roughly 35.6% are rated “Good,” 63.5% “Fair,” and 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

104

Public highway bridges in Decatur County

Good condition

35.6%

37 of 104 rated 7-9

Fair condition

63.5%

66 of 104 rated 5-6

Poor condition

1 of 104 rated 4 or below

In-state Poor-share rank

#6 of 95

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

Condition distribution

Share of 104 NBI-tracked bridges by lowest applicable component rating.

Good

35.6% (37)

Fair

63.5% (66)

Poor

1% (1)

Decatur County's Poor-condition bridges carry 294 vehicle crossings a day

That is 0.2% of the county's reported daily bridge traffic on 1% of its bridges: Poor-condition structures carry less traffic than their share of the inventory. Each Poor bridge averages 294 crossings a day against 1,156 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 104 of 104 bridges in this county that report an average daily traffic count. Source: FHWA National Bridge Inventory, 2024 release.

28.8% of Decatur County's bridges have passed the 50-year mark

30 of the 104 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 35.6% 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 100% of the county's Poor-condition bridge traffic

FAS 69 over STEWMANS CREEK, built 1950, carries 294 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 1-bridge count understates how much of the daily burden sits on a single crossing.

Share is of the 294 daily crossings on Poor-rated bridges that report a traffic count. Source: FHWA National Bridge Inventory, 2024 release.

1930s

7
1940s

2
1950s

12
1960s

5
1970s

14
1980s

22
1990s

19
2000s

12
2010s

9
2020s

2

What this shows Construction peaked in the 1980s, when 22 of the county's bridges still in the inventory were built, which is 21.2% 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 Decatur County compares with Tennessee's closest counties by inventory size

The 5 Tennessee counties nearest Decatur County in number of bridges, with their condition splits. Its 1% Poor share is the 1st-lowest of these 6. Its average build year of 1982 against a peer-group mean of 1977 is 5 years newer.

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

Bridge inventory size and condition shares for Decatur County and the 5 Tennessee counties closest to it in inventory size
County	Bridges	Good	Fair	Poor	Avg. built
Scott County	111	24.3%	71.2%	4.5%	1973
Johnson County	109	44%	51.4%	4.6%	1972
Decatur County (this page)	104	35.6%	63.5%	1%	1982
DeKalb County	100	23%	70%	7%	1977
Rhea County	100	34%	59%	7%	1979
Claiborne County	98	35.7%	60.2%	4.1%	1985

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

Similar inventory size

Nearest county inventories outside TN (104 bridges here).

Nassau County, FL · 104 bridges
Brooks County, GA · 104 bridges
Grady County, GA · 104 bridges
Bonner County, ID · 104 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 104 Good 37 Fair 66 Poor 1

Fair-condition bridges (66)

Sort:

Decatur County Bridge Snapshot

Condition distribution

Decatur County's Poor-condition bridges carry 294 vehicle crossings a day

28.8% of Decatur County's bridges have passed the 50-year mark

One structure carries 100% of the county's Poor-condition bridge traffic

How Decatur 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

Fair-condition bridges (66)

FAP 20

NFA 2732

FAP 100

FAP 100

NFA 2732

FAP 20

NFA A018

NFA A299

NFA A511

NFA 2732

FAP 69

FAS 202

NFA 1739 (SA 2004)

NFA 1758 (SA 2002)

NFA A274

FAP 100

FAS 114

FAP 69

NFA A059

NFA A293

I40

I40

NFA A389

FAS 202

NFA 5577 (SA 2005)

FAP 69

NFA 905 (SA 2009)

NFA 905 (SA 2009)

FAS 202

NFA 1741 (SA 2015)

NFA A032 (SA 2006)

NFA A032

NFA A041

NFA A047

NFA A047

NFA A060

NFA A062

NFA A099

NFA A102

NFA A160

NFA 1705 (SA 2011)

NFA A242

NFA A255

NFA A262

NFA A289

NFA 1705 (SA 2011)

NFA A013

NFA A307

NFA 1708

NFA 1708

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