Total bridges
248
Public highway bridges in Cherokee County
County profile · official public datasets
248 public highway bridges tracked in the FHWA National Bridge Inventory: 34.3% rated Good, 36.7% Fair, 29% Poor.
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.
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.
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
Share of 248 NBI-tracked bridges by lowest applicable component rating.
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.
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.
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.
248 bridges with a recorded construction year, grouped by decade
1900–1909
16 bridges
1910–1919
20 bridges
1920–1929
23 bridges
1930–1939
9 bridges
1940–1949
10 bridges
1950–1959
7 bridges
1960–1969
20 bridges
1970–1979
37 bridges
1980–1989
29 bridges
1990–1999
19 bridges
2000–2009
28 bridges
2010–2019
24 bridges
2020–2029
6 bridges
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.
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.
| 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.
Two NBI-derived peer sets for Cherokee County, both outside Iowa so the neighborhoods are not the same-state size table above.
Nearest county inventories outside IA (248 bridges here).
Nearest mean year-built outside IA (1968 here).
Source: FHWA National Bridge Inventory, 2024 release. Peers floor at 10 bridges so stub inventories cannot own the match.
Over: MAPLE RIVER
090392801, Cherokee, IA
Over: BR SILVER CR
090401104, Cherokee, IA
Over: WILLOW CREEK
090411901, Cherokee, IA
Over: PERRY CREEK
091400501, Cherokee, IA
Over: WILLOW CREEK
091410701, Cherokee, IA
Over: ROCK CREEK
091412202, Cherokee, IA
Over: FIDDLE CREEK
091420501, Cherokee, IA
Over: CREEK
093411205, Cherokee, IA
Over: BEAR CREEK
093411502, Cherokee, IA
Over: PITCHER 153
091392001, Cherokee, IA
Over: RAILROAD CREEK
000000000, Cherokee, IA
Over: RAILROAD CREEK
000000000, Cherokee, IA
Over: RAILROAD CREEK
000000000, Cherokee, IA
Over: SMALL CREEK
091420103, Cherokee, IA
Over: FIDDLE CREEK
091421701, Cherokee, IA
Over: W FORK LITTLE SIOUX RVR
092422402, Cherokee, IA
Over: WEST FORK LITTLE SIOUX
092422401, Cherokee, IA
Over: STREAM
093391604, Cherokee, IA
Over: ROCK CREEK
090410401, Cherokee, IA
Over: SIOUX RIVER
093422501, Cherokee, IA
Over: SMALL CREEK
090423602, Cherokee, IA
Over: MAPLE RIVER
092391201, Cherokee, IA
Over: MAPLE RIVER
091392001, Cherokee, IA
Over: MAPLE RIVER
091393201, Cherokee, IA
Over: CREEK
093391401, Cherokee, IA
Over: WEST FORK LITTLE SIOUX
091422902, Cherokee, IA
Over: ROCK CREEK
091412801, Cherokee, IA
Over: FIDDLE CREEK
091421702, Cherokee, IA
Over: FIDDLE CREEK
091423001, Cherokee, IA
Over: GREY CREEK
093402703, Cherokee, IA
Over: GREY CREEK
093403403, Cherokee, IA
Over: MAPLE RIVER
090390501, Cherokee, IA
Over: RAILROAD CREEK
000000000, Cherokee, IA
Over: N PIERSON CREEK
090422201, Cherokee, IA
Over: LITTLE MAPLE RIVER
090392502, Cherokee, IA
Over: BR PERRY CREEK
091401802, Cherokee, IA
Over: MAPLE RIVER
090392001, Cherokee, IA
Over: PITCHER CREEK
091393502, Cherokee, IA
Over: MAPLE RIVER
092392202, Cherokee, IA
Over: MAPLE CREEK
091390401, Cherokee, IA
Over: FOUR MILE CREEK
093411802, Cherokee, IA
Over: SMALL CREEK
092412402, Cherokee, IA
Over: PITCHER CREEK
091392502, Cherokee, IA
Over: CREEK
093413401, Cherokee, IA
Over: OVERFLOW CHANNEL
090390902, Cherokee, IA
Over: PERRY CREEK
091401901, Cherokee, IA
Over: ROCK CREEK
091413301, Cherokee, IA
Over: MILL CREEK
093410102, Cherokee, IA
Over: FIDDLE CREEK
092422901, Cherokee, IA
Over: PITCHER CREEK
091393501, Cherokee, IA
Read our methodology - how this data is sourced, computed, and verified.
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.