120TH St over W Br Floyd River
Plymouth County, Iowa · rated Poor in the 2025 National Bridge Inventory
United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled
- 120TH St over W Br Floyd River in Plymouth County, Iowa, is rated in poor condition in the 2025 National Bridge Inventory (as of ).
- Its lowest-rated component is the substructure, rated 3 (serious condition) on the 0-9 scale.
- It was built in 1941, making it 84 years old at the 2025 inventory.
- It carries about 20 vehicles a day (traffic count year 2022).
- Its listed owner is the county highway agency.
- It is one of 90 of the 430 inventoried bridges in Plymouth County rated poor (20.9%); 90 (20.9%) 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 June 2024, on a 12-month routine inspection cycle.
- It has fracture-critical members (NBI item 92A): steel tension members without a redundant load path, which get their own scheduled inspections.
- 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 → (42.88047, -96.19601)
Component ratings
| Component | Rating (2024) | Rating (2025) | FHWA scale meaning |
|---|---|---|---|
| Deck | 6 | 6 | Satisfactory condition |
| Superstructure | 4 | 4 | Poor condition |
| Substructure | 3 | 3 | Serious condition |
Bridge details
| Structure | Steel through truss |
| Length | about 143 ft |
| Location | 093451803 |
| NBI structure number | 000000000276670 |
| Condition class | Poor |
| Traffic status (item 41) | Posted for load |
| Last inspection (item 90) | June 2024 |
| Inspection interval (item 91) | 12 months |
| Scour (item 113) | 8: foundations stable, scour above the top of the footing |
| Fracture critical (item 92A) | Yes |
Source: FHWA National Bridge Inventory, 2025 data as reported by the Iowa department of transportation.
Busiest bridges in Plymouth County
| Bridge | Built | Vehicles/day | Condition |
|---|---|---|---|
| US 75 over Stream | 1999 | 18,200 | Fair |
| US 75 over Stream | 2019 | 14,900 | Good |
| US 75 over Stream | 2019 | 14,900 | Good |
| US 75 over Stream | 2019 | 14,900 | Good |
| US 75 over Stream | 2019 | 14,900 | Good |
| US 75 over Stream | 1926 | 14,000 | Poor |
All bridges nearby: Plymouth County, IA bridge conditions · every bridge in Plymouth County · Iowa bridges.
Background: how bridge ratings work · what "poor" and "structurally deficient" actually mean · how often bridges are inspected.