Bridge conditions in Story County, Iowa
302 inventoried bridges · 40 rated poor · 2025 National Bridge Inventory
United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled
Story County has 40 bridges rated poor out of 302 inventoried, a 13.2% share that puts it well above the national rate of about 7%.
- 40 of the 302 bridges in Story County, Iowa, are rated in poor condition (13.2%) in the 2025 National Bridge Inventory, as of .
- 102 bridges (33.8%) are rated good and 160 (53.0%) fair.
- The median Story County bridge was built in 1968.
- The busiest poor-rated bridge is Lincoln Way over Ioway Creek (built 1957), carrying about 8,224 vehicles a day.
Good 33.8% · Fair 53.0% · Poor 13.2% of 302 bridges
Bridges rated poor
Every bridge in the county with a poor rating, busiest first. Poor means a major component is rated 4 or lower on FHWA's 0-9 scale; it is a repair flag, not a closure notice.
Busiest bridges in the county
| Bridge | Built | Vehicles/day | Condition |
|---|---|---|---|
| I-35 over Ballard Creek | 1964 | 48,300 | Fair |
| I-35 over Walnut Creek | 1964 | 48,300 | Fair |
| I 35 over South Skunk Rvr Overflow | 2017 | 48,300 | Good |
| I-35 over Drainage Ditch | 1967 | 28,300 | Good |
| US 69 over Ioway Creek | 1924 | 24,600 | Good |
| NB I-35 over Bike Path | 1964 | 24,150 | Fair |
| I 35 NB over South Skunk River | 2018 | 24,150 | Good |
| US 30 over Worrell Creek | 1971 | 23,700 | Good |
| SB I-35 over Bike Path | 1964 | 23,300 | Fair |
| I 35 SB over South Skunk River | 2017 | 23,300 | Good |
Source: FHWA National Bridge Inventory, 2025. Counts cover inventoried highway bridges over 20 feet; ratings are reported by the state DOT.
Every bridge in Story County → - all 302, busiest first, each with its own condition record.
All of Iowa: Iowa bridge conditions by county · every download on the data page.
Background: how bridge ratings work · what "poor" and "structurally deficient" actually mean · how often bridges are inspected.