Total bridges
382
Public highway bridges in Jasper County
County profile · official public datasets
382 public highway bridges tracked in the FHWA National Bridge Inventory: 38.5% rated Good, 32.5% Fair, 29.1% Poor.
The verdict
According to the Federal Highway Administration's 2024 National Bridge Inventory.
Jasper County posts a higher-than-median Poor-condition share among rated counties in the state across mid-size county bridge 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, Jasper County ranks #77 of 99 Iowa counties with at least 5 public highway bridges on Poor-condition share (lower share ranks better; currently 29.1%). Jasper County, Iowa contains 382 public highway bridges. Roughly 38.5% are rated “Good,” 32.5% “Fair,” and 29.1% “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
382
Public highway bridges in Jasper County
Good condition
38.5%
147 of 382 rated 7-9
Fair condition
32.5%
124 of 382 rated 5-6
Poor condition
29.1%
111 of 382 rated 4 or below
In-state Poor-share rank
#77 of 99
Among Iowa counties with 5+ bridges, lower share ranks better
Share of 382 NBI-tracked bridges by lowest applicable component rating.
That is 2.3% of the county's reported daily bridge traffic on 28.9% of its bridges: Poor-condition structures carry less traffic than their share of the inventory. Each Poor bridge averages 151 crossings a day against 968 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 381 of 382 bridges in this county that report an average daily traffic count. Source: FHWA National Bridge Inventory, 2024 release.
175 of the 382 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 38.5% 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.
HIGHWAY F-48 W over SMALL STREAM, built 1949, carries 1,530 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 111-bridge count understates how much of the daily burden sits on a single crossing.
Share is of the 16,570 daily crossings on Poor-rated bridges that report a traffic count. Source: FHWA National Bridge Inventory, 2024 release.
382 bridges with a recorded construction year, grouped by decade
1910–1919
12 bridges
1920–1929
26 bridges
1930–1939
22 bridges
1940–1949
19 bridges
1950–1959
27 bridges
1960–1969
50 bridges
1970–1979
39 bridges
1980–1989
28 bridges
1990–1999
45 bridges
2000–2009
37 bridges
2010–2019
57 bridges
2020–2029
20 bridges
What this shows Construction peaked in the 2010s, when 57 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 5 to 14 years old in the 2024 inventory. Its average build year (1977) matches the Iowa average (1979).
The 5 Iowa counties nearest Jasper County in number of bridges, with their condition splits. Its 29.1% Poor share is the 6th-lowest of these 6. Its average build year of 1977 against a peer-group mean of 1982 is 5 years older.
Showing the 5 closest of 98 Iowa counties eligible for comparison.
| County | Bridges | Good | Fair | Poor | Avg. built |
|---|---|---|---|---|---|
| Jasper County (this page) | 382 | 38.5% | 32.5% | 29.1% | 1977 |
| Benton County | 374 | 34.2% | 42.8% | 23% | 1984 |
| Clinton County | 372 | 66.7% | 30.4% | 3% | 1986 |
| Johnson County | 372 | 39.5% | 50.3% | 10.2% | 1979 |
| Fayette County | 362 | 35.1% | 40.3% | 24.6% | 1974 |
| Dubuque County | 346 | 50.6% | 40.8% | 8.7% | 1989 |
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 Jasper County's. Source: FHWA National Bridge Inventory, 2024 release.
Two NBI-derived peer sets for Jasper County, both outside Iowa so the neighborhoods are not the same-state size table above.
Nearest county inventories outside IA (382 bridges here).
Nearest mean year-built outside IA (1977 here).
Source: FHWA National Bridge Inventory, 2024 release. Peers floor at 10 bridges so stub inventories cannot own the match.
Over: BYERS BRANCH CREEK
081213404, Jasper, IA
Over: BUCK CREEK
078201302, Jasper, IA
Over: SMALL STREAM
079210901, Jasper, IA
Over: SMALL STREAM
079190513, Jasper, IA
Over: SMALL STREAM
078191104, Jasper, IA
Over: RED ROCK CREEK
079212501, Jasper, IA
Over: CAMP CREEK
078213101, Jasper, IA
Over: ROCK CREEK
081180102, Jasper, IA
Over: BRUSH CREEK
081170202, Jasper, IA
Over: LITTLE SNIPE CREEK
081191401, Jasper, IA
Over: BYERS BRANCH CREEK
081213002, Jasper, IA
Over: SMALL STREAM
078203402, Jasper, IA
Over: CHERRY CREEK
080192009, Jasper, IA
Over: N. SKUNK RIVER
081190502, Jasper, IA
Over: S SKUNK RIVER
078191003, Jasper, IA
Over: SMALL STREAM
081203203, Jasper, IA
Over: SMALL STREAM
079183303, Jasper, IA
Over: ELK CREEK
078181003, Jasper, IA
Over: ROCK CREEK
081172001, Jasper, IA
Over: SMALL STREAM
080182603, Jasper, IA
Over: INDIAN CREEK
080202901, Jasper, IA
Over: WALNUT CREEK
078213401, Jasper, IA
Over: CARSON CREEK
078190303, Jasper, IA
Over: BEAR CREEK
080182401, Jasper, IA
Over: CHERRY CREEK
080190703, Jasper, IA
Over: SMALL STREAM
080201802, Jasper, IA
Over: SMALL STREAM
080210404, Jasper, IA
Over: SMALL
078180306, Jasper, IA
Over: NORTH SKUNK RIVER
078171207, Jasper, IA
Over: SMALL STREAM
080211304, Jasper, IA
Over: SMALL STREAM
079172204, Jasper, IA
Over: NORTH SKUNK RIVER
081190902, Jasper, 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.