320TH St over Rock Creek
Fremont County, Iowa · rated Poor in the 2025 National Bridge Inventory
United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled
- 320TH St over Rock Creek in Fremont County, Iowa, is rated in poor condition in the 2025 National Bridge Inventory (as of ).
- Its lowest-rated component is the substructure, rated 4 (poor condition) on the 0-9 scale.
- It was built in 1962, making it 63 years old at the 2025 inventory.
- It carries about 15 vehicles a day (traffic count year 2021).
- Its listed owner is the county highway agency.
- It is one of 38 of the 179 inventoried bridges in Fremont County rated poor (21.2%); 38 (21.2%) are rated poor.
- Its traffic status in the 2025 inventory is posted for load (NBI item 41).
- Its condition class and component ratings are unchanged from the 2024 inventory.
- Its most recent inspection on record is dated May 2023, on a 24-month routine inspection cycle.
- A poor rating means at least one major component - deck, superstructure, or substructure - is rated 4 or lower on FHWA's 0-9 scale. It does not by itself mean the bridge is unsafe; bridges judged unsafe are closed or load-restricted by their owners.
View this bridge on a map → (40.58348, -95.41204)
Component ratings
| Component | Rating (2024) | Rating (2025) | FHWA scale meaning |
|---|---|---|---|
| Deck | 6 | 6 | Satisfactory condition |
| Superstructure | 6 | 6 | Satisfactory condition |
| Substructure | 4 | 4 | Poor condition |
Bridge details
| Structure | Timber stringer or multi-beam girder |
| Length | about 32 ft |
| Location | 067402604 |
| NBI structure number | 000000000158830 |
| Condition class | Poor |
| Traffic status (item 41) | Posted for load |
| Last inspection (item 90) | May 2023 |
| Inspection interval (item 91) | 24 months |
| Scour (item 113) | 8: foundations stable, scour above the top of the footing |
Source: FHWA National Bridge Inventory, 2025 data as reported by the Iowa department of transportation.
Busiest bridges in Fremont County
| Bridge | Built | Vehicles/day | Condition |
|---|---|---|---|
| Ia 2 over Missouri River | 1986 | 8,300 | Good |
| Ia 2 over Overflow | 2022 | 8,000 | Good |
| I 29 NB over over Aband RR & Lcl Rd | 1972 | 7,850 | Fair |
| I 29 SB over Aband RR & Dike Rd | 1972 | 7,850 | Fair |
| NB I-29 over BNSF RR & Main St | 1972 | 7,300 | Fair |
| SB I-29 over BNSF RR & Main St | 1972 | 7,300 | Fair |
All bridges nearby: Fremont County, IA bridge conditions · every bridge in Fremont County · Iowa bridges.
Background: how bridge ratings work · what "poor" and "structurally deficient" actually mean · how often bridges are inspected.