County profile · official public datasets

Cherokee County, IA

248 public highway bridges tracked in the FHWA National Bridge Inventory: 34.3% rated Good, 36.7% Fair, 29% Poor.

248
Public bridges: 34.3%
Good condition: 29%
Poor condition

The verdict

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

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

76th
of 99 on Poor share: 29%
Poor-condition share: 248
public highway bridges: 1968
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.

Cherokee County Bridge Snapshot

According to the Federal Highway Administration's 2024 National Bridge Inventory, Cherokee County ranks #76 of 99 Iowa counties with at least 5 public highway bridges on Poor-condition share (lower share ranks better; currently 29%). Cherokee County, Iowa contains 248 public highway bridges. Roughly 34.3% are rated “Good,” 36.7% “Fair,” and 29% “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

248

Public highway bridges in Cherokee County

Good condition

34.3%

85 of 248 rated 7-9

Fair condition

36.7%

91 of 248 rated 5-6

Poor condition

29%

72 of 248 rated 4 or below

In-state Poor-share rank

#76 of 99

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

Condition distribution

Share of 248 NBI-tracked bridges by lowest applicable component rating.

Good

34.3% (85)

Fair

36.7% (91)

Poor

29% (72)

Cherokee County's Poor-condition bridges carry 11,294 vehicle crossings a day

That is 10.7% of the county's reported daily bridge traffic on 29.1% of its bridges: Poor-condition structures carry less traffic than their share of the inventory. Each Poor bridge averages 157 crossings a day against 274 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 247 of 248 bridges in this county that report an average daily traffic count. Source: FHWA National Bridge Inventory, 2024 release.

52% of Cherokee County's bridges have passed the 50-year mark

129 of the 248 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 34.3% 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 31.2% of the county's Poor-condition bridge traffic

W BLUFF ST over RAILROAD CREEK, built 1961, carries 3,529 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 72-bridge count understates how much of the daily burden sits on a single crossing.

Share is of the 11,294 daily crossings on Poor-rated bridges that report a traffic count. Source: FHWA National Bridge Inventory, 2024 release.

1900s

16
1910s

20
1920s

23
1930s

9
1940s

10
1950s

7
1960s

20
1970s

37
1980s

29
1990s

19
2000s

28
2010s

24
2020s

6

What this shows Construction peaked in the 1970s, when 37 of the county's bridges still in the inventory were built, which is 14.9% of those with a recorded year. That cohort is now 45 to 54 years old in the 2024 inventory. Its average build year is 1968, 11 years older than the Iowa average of 1979.

How Cherokee County compares with Iowa's closest counties by inventory size

The 5 Iowa counties nearest Cherokee County in number of bridges, with their condition splits. Its 29% Poor share is the 5th-lowest of these 6. Its average build year of 1968 against a peer-group mean of 1979 is 11 years older.

Showing the 5 closest of 98 Iowa counties eligible for comparison.

Bridge inventory size and condition shares for Cherokee County and the 5 Iowa counties closest to it in inventory size
County	Bridges	Good	Fair	Poor	Avg. built
Carroll County	249	48.6%	44.6%	6.8%	1977
Poweshiek County	248	25%	33.1%	41.9%	1974
Cherokee County (this page)	248	34.3%	36.7%	29%	1968
Jackson County	246	26.4%	56.5%	17.1%	1983
Hardin County	241	36.1%	36.1%	27.8%	1981
Iowa County	241	37.3%	43.6%	19.1%	1980

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

Similar inventory size

Nearest county inventories outside IA (248 bridges here).

Crawford County, AR · 248 bridges
Lowndes County, MS · 248 bridges
Herkimer County, NY · 248 bridges
Rockland County, NY · 248 bridges

Similar average build year

Nearest mean year-built outside IA (1968 here).

Montgomery County, PA · avg 1968 · 828 bridges
San Joaquin County, CA · avg 1968 · 644 bridges
Providence County, RI · avg 1968 · 476 bridges
Imperial County, CA · avg 1968 · 444 bridges

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

All 248 Good 85 Fair 91 Poor 72

All bridges (248)

Sort:

Cherokee County Bridge Snapshot

Condition distribution

Cherokee County's Poor-condition bridges carry 11,294 vehicle crossings a day

52% of Cherokee County's bridges have passed the 50-year mark

One structure carries 31.2% of the county's Poor-condition bridge traffic

How Cherokee County compares with Iowa's closest counties by inventory size

Nationwide counties with similar inventory size or average build year

Similar inventory size

Similar average build year

All bridges (248)

LOCAL- 600TH ST

OLD 21 ROAD

FM-HIGH CTRY.RD

M 21 (V AVE)

US 59

FM-530TH ST.

LOCAL-520TH ST

FM

620TH ST

500TH ST

C43 550TH ST

630TH ST

LOCAL-510TH ST.

FM- 510TH ST

LOCAL-E AVE.

LOCAL-600TH ST

LOCAL Y AVE

LOCAL-640TH ST

FM-W AVE.

US 59

LOCAL- 600TH ST

P AVE

LOCAL Y AVE

FM- WASHTA RD

US 59

IA 7

LOCAL-640TH ST

Q AVE

LOCAL- 630TH ST

LOCAL 540TH ST.

LOCAL 550TH ST.

FM J AVE.

LOCAL 540TH ST

LOCAL 440TH ST

FM J AVE

570TH ST

EUCLID AVE

UNION ST

E. WILLOW ST

LOCAL 540TH ST

LOCAL 560TH ST

FM-F AVE.

510TH ST

LCL MRT.ACC.RD

LOCAL- 600TH ST

LOCAL 460TH ST

LOCAL- F AVE

LOCAL-490TH ST

LOCAL 570TH ST

590TH ST

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