Total bridges
185
Public highway bridges in Osceola County
County profile · official public datasets
Osceola County, IA
185 public highway bridges tracked in the FHWA National Bridge Inventory: 38.4% rated Good, 53% Fair, 8.6% Poor.
- 185
- Public bridges
- 38.4%
- Good condition
- 8.6%
- Poor condition
The verdict
According to the Federal Highway Administration's 2024 National Bridge Inventory.
Osceola County pairs a top-quartile lowest Poor-condition share among rated counties in the state with an older average build year than the state inventory.
- Top 12%
- lowest Poor share in state
- 8.6%
- Poor-condition share
- 185
- public highway bridges
- 1965
- 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.
Osceola County Bridge Snapshot
According to the Federal Highway Administration's 2024 National Bridge Inventory, Osceola County ranks #12 of 99 Iowa counties with at least 5 public highway bridges on Poor-condition share (lower share ranks better; currently 8.6%). Osceola County, Iowa contains 185 public highway bridges. Roughly 38.4% are rated “Good,” 53% “Fair,” and 8.6% “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.
Good condition
38.4%
71 of 185 rated 7-9
Fair condition
53%
98 of 185 rated 5-6
Poor condition
8.6%
16 of 185 rated 4 or below
In-state Poor-share rank
#12 of 99
Among Iowa counties with 5+ bridges, lower share ranks better
Condition distribution
Share of 185 NBI-tracked bridges by lowest applicable component rating.
Good 38.4% (71)
Fair 53% (98)
Poor 8.6% (16)
Osceola County's Poor-condition bridges carry 2,010 vehicle crossings a day
That is 2.3% of the county's reported daily bridge traffic on 8.6% of its bridges: Poor-condition structures carry less traffic than their share of the inventory. Each Poor bridge averages 126 crossings a day against 754 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 185 of 185 bridges in this county that report an average daily traffic count. Source: FHWA National Bridge Inventory, 2024 release.
62.7% of Osceola County's bridges have passed the 50-year mark
116 of the 185 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 38.4% 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 39.7% of the county's Poor-condition bridge traffic
NORTHWEST BLVD over OTTER CREEK, built 1931, carries 797 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 16-bridge count understates how much of the daily burden sits on a single crossing.
Share is of the 2,010 daily crossings on Poor-rated bridges that report a traffic count. Source: FHWA National Bridge Inventory, 2024 release.
When Osceola County's bridges were built
185 bridges with a recorded construction year, grouped by decade
- 1900s 6
1900–1909
6 bridges
- 1920s 1
1920–1929
1 bridges
- 1930s
1930–1939
27 bridges
- 1940s
1940–1949
26 bridges
- 1950s
1950–1959
31 bridges
- 1960s
1960–1969
15 bridges
- 1970s
1970–1979
27 bridges
- 1980s 9
1980–1989
9 bridges
- 1990s 9
1990–1999
9 bridges
- 2000s
2000–2009
27 bridges
- 2010s 6
2010–2019
6 bridges
- 2020s 1
2020–2029
1 bridges
What this shows Construction peaked in the 1950s, when 31 of the county's bridges still in the inventory were built, which is 16.8% of those with a recorded year. That cohort is now 65 to 74 years old in the 2024 inventory. Its average build year is 1965, 14 years older than the Iowa average of 1979.
How Osceola County compares with Iowa's closest counties by inventory size
The 5 Iowa counties nearest Osceola County in number of bridges, with their condition splits. Its 8.6% Poor share is the 1st-lowest of these 6. Its average build year of 1965 against a peer-group mean of 1977 is 12 years older.
Showing the 5 closest of 98 Iowa counties eligible for comparison.
| County | Bridges | Good | Fair | Poor | Avg. built |
|---|---|---|---|---|---|
| Adams County | 186 | 10.2% | 45.2% | 44.6% | 1967 |
| Osceola County (this page) | 185 | 38.4% | 53% | 8.6% | 1965 |
| Mills County | 184 | 29.3% | 51.6% | 19% | 1976 |
| Appanoose County | 183 | 41% | 27.9% | 31.1% | 1981 |
| Keokuk County | 183 | 34.4% | 45.9% | 19.7% | 1980 |
| Ida County | 182 | 42.9% | 40.7% | 16.5% | 1983 |
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 Osceola 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 Osceola County, both outside Iowa so the neighborhoods are not the same-state size table above.
Similar inventory size
Nearest county inventories outside IA (185 bridges here).
- Chambers County, AL · 185 bridges
- Maui County, HI · 185 bridges
- Lawrence County, IL · 185 bridges
- Saline County, IL · 185 bridges
Similar average build year
Nearest mean year-built outside IA (1965 here).
- Windsor County, VT · avg 1965 · 483 bridges
- Bedford County, PA · avg 1965 · 417 bridges
- Crawford County, PA · avg 1965 · 399 bridges
- Harper County, KS · avg 1965 · 372 bridges
Source: FHWA National Bridge Inventory, 2024 release. Peers floor at 10 bridges so stub inventories cannot own the match.
Poor-condition bridges (16)
LOCAL
PoorOver: OCHEYEDAN RIVER
098390604, Osceola, IA
Built 1900 Load: 0.0 t ADT: 11
LOCAL
PoorOver: LITTLE OCHEYDAN RIVER
098402301, Osceola, IA
Built 1900 Load: 0.0 t ADT: 5
LOCAL
PoorOver: LITTLE ROCK RIVER
100423001, Osceola, IA
Built 1941 Load: 9.6 t ADT: 15
NORTHWEST BLVD
PoorOver: OTTER CREEK
000600230, Osceola, IA
Built 1931 Load: 10.8 t ADT: 797
LOCAL
PoorOver: STREAM
099413302, Osceola, IA
Built 1944 Load: 10.9 t ADT: 21
LOCAL
PoorOver: LITTLE OCHEYEDAN RIVER
099403302, Osceola, IA
Built 1934 Load: 11.1 t ADT: 21
LOCAL
PoorOver: OCHEYEDAN RIVER
100412501, Osceola, IA
Built 1900 Load: 12.2 t ADT: 26
FM
PoorOver: CLOVERDALE CREEK
099412902, Osceola, IA
Built 1958 Load: 12.4 t ADT: 459
LOCAL
PoorOver: OTTER CREEK
099421102, Osceola, IA
Built 1949 Load: 16.5 t ADT: 5
LOCAL
PoorOver: CREEK
098390504, Osceola, IA
Built 1936 Load: 16.8 t ADT: 62
FM
PoorOver: OCHEYEDAN RIVER
099403501, Osceola, IA
Built 1951 Load: 17.1 t ADT: 131
LOCAL
PoorOver: LITTLE OCHEYDAN RIVER
098400401, Osceola, IA
Built 1949 Load: 18.2 t ADT: 15
LOCAL
PoorOver: OTTER CREEK
099413102, Osceola, IA
Built 1949 Load: 18.7 t ADT: 30
LOCAL
PoorOver: STREAM
100411403, Osceola, IA
Built 1957 Load: 19.0 t ADT: 41
LOCAL
PoorOver: STREAM
099420502, Osceola, IA
Built 1943 Load: 21.4 t ADT: 21
FM
PoorOver: LITTLE OCHEYEDAN RIVER
098402402, Osceola, IA
Built 1986 Load: 33.3 t ADT: 350
Read our methodology - how this data is sourced, computed, and verified.
Related
Data sourced from official public datasets. See our methodology for details. Retrieved and formatted by PlainBridges
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.