1780 Hill Ave over Trib Boone River #8
Hancock County, Iowa · rated Poor in the 2025 National Bridge Inventory
United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled
- 1780 Hill Ave over Trib Boone River #8 in Hancock 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 1957, making it 68 years old at the 2025 inventory.
- It carries about 15 vehicles a day (traffic count year 2022).
- Its listed owner is the county highway agency.
- It is one of 27 of the 135 inventoried bridges in Hancock County rated poor (20.0%); 27 (20.0%) are rated poor.
- Its traffic status in the 2025 inventory is open, no restriction (NBI item 41).
- It was rated fair in the 2024 inventory and is now poor (substructure 5 to 4).
- Its most recent inspection on record is dated March 2024, 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 → (43.02076, -93.83238)
Component ratings
| Component | Rating (2024) | Rating (2025) | FHWA scale meaning |
|---|---|---|---|
| Deck | 6 | 6 | Satisfactory condition |
| Superstructure | 6 | 6 | Satisfactory condition |
| Substructure | 5 | 4 | Poor condition |
Bridge details
| Structure | Prestressed concrete stringer or multi-beam girder |
| Length | about 57 ft |
| Location | 095252902 |
| NBI structure number | 000000000173450 |
| Condition class | Poor |
| Traffic status (item 41) | Open, no restriction |
| Last inspection (item 90) | March 2024 |
| 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 Hancock County
| Bridge | Built | Vehicles/day | Condition |
|---|---|---|---|
| US 18 over E Branch Iowa River | 2002 | 6,500 | Good |
| US 18 over Drainage Ditch | 1958 | 5,200 | Fair |
| US 18 over West Fork Iowa River | 1958 | 5,200 | Fair |
| B-14 over Private Dr | 1972 | 3,502 | Fair |
| US 18 over Boone River | 1959 | 2,980 | Fair |
| US 18 over Branch Boone River | 1959 | 2,980 | Fair |
All bridges nearby: Hancock County, IA bridge conditions · every bridge in Hancock County · Iowa bridges.
Background: how bridge ratings work · what "poor" and "structurally deficient" actually mean · how often bridges are inspected.