County profile · official public datasets

Cobb County, GA

414 public highway bridges tracked in the FHWA National Bridge Inventory: 89.1% rated Good, 10.9% Fair, 0% Poor.

414
Public bridges: 89.1%
Good condition: 0%
Poor condition

The verdict

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

Cobb County pairs a top-1% lowest Poor-condition share among rated counties in the state with a newer average build year than the state inventory.

Top 1%
lowest Poor share in state: 0%
Poor-condition share: 414
public highway bridges: 1987
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.

Cobb County Bridge Snapshot

According to the Federal Highway Administration's 2024 National Bridge Inventory, Cobb County ranks #1 of 159 Georgia counties with at least 5 public highway bridges on Poor-condition share (lower share ranks better; currently 0%). Cobb County, Georgia contains 414 public highway bridges. Roughly 89.1% are rated “Good,” 10.9% “Fair,” and 0% “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

414

Public highway bridges in Cobb County

Good condition

89.1%

369 of 414 rated 7-9

Fair condition

10.9%

45 of 414 rated 5-6

Poor condition

0 of 414 rated 4 or below

In-state Poor-share rank

#1 of 159

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

Condition distribution

Share of 414 NBI-tracked bridges by lowest applicable component rating.

Good

89.1% (369)

Fair

10.9% (45)

Poor

0% (0)

31.2% of Cobb County's bridges have passed the 50-year mark

129 of the 414 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 89.1% 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.

pre-1900

1
1920s

3
1930s

7
1940s

9
1950s

18
1960s

54
1970s

63
1980s

54
1990s

89
2000s

43
2010s

64
2020s

9

What this shows Construction peaked in the 1990s, when 89 of the county's bridges still in the inventory were built, which is 21.5% of those with a recorded year. That cohort is now 25 to 34 years old in the 2024 inventory. Its average build year is 1987, 10 years newer than the Georgia average of 1977.

How Cobb County compares with Georgia's closest counties by inventory size

The 5 Georgia counties nearest Cobb County in number of bridges, with their condition splits. Its 0% Poor share is the 1st-lowest of these 6. Its average build year of 1987 against a peer-group mean of 1979 is 8 years newer.

Showing the 5 closest of 158 Georgia counties eligible for comparison.

Bridge inventory size and condition shares for Cobb County and the 5 Georgia counties closest to it in inventory size
County	Bridges	Good	Fair	Poor	Avg. built
Cobb County (this page)	414	89.1%	10.9%	0%	1987
DeKalb County	392	73.7%	24.7%	1.5%	1971
Gwinnett County	317	89.3%	10.7%	0%	1989
Chatham County	265	75.8%	23%	1.1%	1985
Bibb County	220	76.4%	23.6%	0%	1974
Bartow County	219	67.1%	30.6%	2.3%	1977

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

Similar inventory size

Nearest county inventories outside GA (414 bridges here).

Mercer County, NJ · 414 bridges
Stark County, OH · 415 bridges
Macomb County, MI · 417 bridges
St. Charles County, MO · 417 bridges

Similar average build year

Nearest mean year-built outside GA (1987 here).

St. Louis County, MO · avg 1987 · 912 bridges
Ellis County, TX · avg 1987 · 691 bridges
St. Louis County, MN · avg 1987 · 663 bridges
Palm Beach County, FL · avg 1987 · 610 bridges

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

All 414 Good 369 Fair 45 Poor 0

Good-condition bridges (369)

Sort:

Cobb County Bridge Snapshot

Condition distribution

31.2% of Cobb County's bridges have passed the 50-year mark

How Cobb County compares with Georgia'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 (369)

R 7-2SB/ML-I285WBR

I-75 MANAGED LANES

I-75 MANAGED LANE

POWDER SPRINGS ROA

SOUTH COBB DRIVE

I-75

I-75

STEINHAUER ROAD

BARNES MILL ROAD

INDIAN HILLS DRIVE

ELLIOTT ROAD

POWDER SPRINGS ROA

I-75 MANAGED LANES

US 41/ SR 3

US 41 / SR 3

US 78/ SR 8

SR 120 LOOP (CBL)

MARS HILL ROAD

SOUTH COBB DRIVE

I-75 (SBL)

I-575 (NBL)

I-575 (SBL)

BELLS FERRY ROAD

OLD HWY 41

OLD HWY 41

BROWNSVILLE ROAD

SHALLOWFORD RD

MAXHAM ROAD

PIEDMONT ROAD

PIEDMONT ROAD

US 78/ SR 8

JIM OWENS ROAD

VILLA RICA ROAD

GREEN FIELD DRIVE

INDIAN HILLS DRIVE

BARCLAY ROAD

OLD FLOYD ROAD

GAYDON ROAD

PERKERSON MILL ROA

SOUTH GORDON ROAD

JAMERSON ROAD

JAMERSON ROAD

CLUBLAND DRIVE

INDIAN HILLS PKY

CANDY LANE

COVERED BR ROAD

BAKER ROAD

ROCK BRIDGE ROAD

MARK AVENUE

I-75 MANAGED LANES

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