County profile · official public datasets

Logan County, OK

284 public highway bridges tracked in the FHWA National Bridge Inventory: 24.3% rated Good, 55.6% Fair, 20.1% Poor.

284
Public bridges: 24.3%
Good condition: 20.1%
Poor condition

The verdict

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

Logan County posts a higher-than-median Poor-condition share among rated counties in the state across mid-size county bridge inventory.

75th
of 77 on Poor share: 20.1%
Poor-condition share: 284
public highway bridges: 1973
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.

Logan County Bridge Snapshot

According to the Federal Highway Administration's 2024 National Bridge Inventory, Logan County ranks #75 of 77 Oklahoma counties with at least 5 public highway bridges on Poor-condition share (lower share ranks better; currently 20.1%). Logan County, Oklahoma contains 284 public highway bridges. Roughly 24.3% are rated “Good,” 55.6% “Fair,” and 20.1% “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

284

Public highway bridges in Logan County

Good condition

24.3%

69 of 284 rated 7-9

Fair condition

55.6%

158 of 284 rated 5-6

Poor condition

20.1%

57 of 284 rated 4 or below

In-state Poor-share rank

#75 of 77

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

Condition distribution

Share of 284 NBI-tracked bridges by lowest applicable component rating.

Good

24.3% (69)

Fair

55.6% (158)

Poor

20.1% (57)

Logan County's Poor-condition bridges carry 5,291 vehicle crossings a day

That is 1.2% of the county's reported daily bridge traffic on 20.1% of its bridges: Poor-condition structures carry less traffic than their share of the inventory. Each Poor bridge averages 93 crossings a day against 1,824 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 284 of 284 bridges in this county that report an average daily traffic count. Source: FHWA National Bridge Inventory, 2024 release.

49.3% of Logan County's bridges have passed the 50-year mark

140 of the 284 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 24.3% 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 9.5% of the county's Poor-condition bridge traffic

E0740 (OLD S.H. 33 over FITZGERALD CREEK, built 1927, carries 500 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 57-bridge count understates how much of the daily burden sits on a single crossing.

Share is of the 5,291 daily crossings on Poor-rated bridges that report a traffic count. Source: FHWA National Bridge Inventory, 2024 release.

1900s

1
1910s

5
1920s

15
1930s

23
1940s

32
1950s

53
1960s

9
1970s

4
1980s

20
1990s

43
2000s

42
2010s

28
2020s

9

What this shows Construction peaked in the 1950s, when 53 of the county's bridges still in the inventory were built, which is 18.7% of those with a recorded year. That cohort is now 65 to 74 years old in the 2024 inventory. Its average build year (1973) matches the Oklahoma average (1977).

How Logan County compares with Oklahoma's closest counties by inventory size

The 5 Oklahoma counties nearest Logan County in number of bridges, with their condition splits. Its 20.1% Poor share is the 6th-lowest of these 6. Its average build year of 1973 against a peer-group mean of 1971 is in line with the group.

Showing the 5 closest of 76 Oklahoma counties eligible for comparison.

Bridge inventory size and condition shares for Logan County and the 5 Oklahoma counties closest to it in inventory size
County	Bridges	Good	Fair	Poor	Avg. built
Jackson County	292	58.6%	39%	2.4%	1964
Bryan County	286	41.6%	48.6%	9.8%	1974
Tillman County	284	69.4%	28.2%	2.5%	1962
Logan County (this page)	284	24.3%	55.6%	20.1%	1973
Blaine County	272	66.9%	26.1%	7%	1976
Rogers County	272	44.9%	46%	9.2%	1978

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

Similar inventory size

Nearest county inventories outside OK (284 bridges here).

Cambria County, PA · 284 bridges
Susquehanna County, PA · 284 bridges
Washington County, TN · 284 bridges
Gonzales County, TX · 284 bridges

Similar average build year

Nearest mean year-built outside OK (1973 here).

Jefferson County, AL · avg 1973 · 1,068 bridges
Erie County, NY · avg 1973 · 906 bridges
Davidson County, TN · avg 1973 · 832 bridges
Lancaster County, PA · avg 1973 · 801 bridges

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

All 284 Good 69 Fair 158 Poor 57

Fair-condition bridges (158)

Sort:

Logan County Bridge Snapshot

Condition distribution

Logan County's Poor-condition bridges carry 5,291 vehicle crossings a day

49.3% of Logan County's bridges have passed the 50-year mark

One structure carries 9.5% of the county's Poor-condition bridge traffic

How Logan County compares with Oklahoma'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 (158)

N3200

E0650

CO. RD. E0760

E0690

E0850

E0610

N3200

E0840

E0740

N3260

N3095

E0750

E0810

I-35 N.B.

I-35 S.B.

E0680

N3070

N3150

E0850

N3140

E0780

N3130 (SOONER RD)

E0750

U.S. 77

N3140

E0760

N3240

S.H. 74

I-35

I-35

E0880

E0810

I-35

I-35

E0870

N3125

E0820

U.S. 77

S.H. 74

U.S. 77

I-35 S.B.

I-35 NB OFF-RAMP

I-35 SB ON-RAMP

I-35

CO. RD. E0880

CHARTER OAK RD.

CAMP RD.

CO. RD. E0810

CO. RD. E0795

COLLEGE AVE.

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