Local - 770TH over Waterway
Cass County, Iowa · rated Good in the 2025 National Bridge Inventory
United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled
- Local - 770TH over Waterway in Cass County, Iowa, is rated in good condition in the 2025 National Bridge Inventory (as of ).
- Its lowest-rated component is the deck, rated 7 (good condition) on the 0-9 scale.
- It was built in 1985, making it 40 years old at the 2025 inventory.
- It carries about 26 vehicles a day (traffic count year 2022).
- Its listed owner is the county highway agency.
- It is one of 80 of the 296 inventoried bridges in Cass County rated good (27.0%); 104 (35.1%) are rated poor.
- Its traffic status in the 2025 inventory is open, no restriction (NBI item 41).
- Its condition class and component ratings are unchanged from the 2024 inventory.
- Its most recent inspection on record is dated March 2024, on a 48-month routine inspection cycle.
- A good rating means every major component - deck, superstructure, substructure, or culvert - is rated 7 or higher on FHWA's 0-9 scale: no more than minor problems.
View this bridge on a map → (41.46097, -94.71991)
Component ratings
| Component | Rating (2024) | Rating (2025) | FHWA scale meaning |
|---|---|---|---|
| Deck | 7 | 7 | Good condition |
| Superstructure | 7 | 7 | Good condition |
| Substructure | 7 | 7 | Good condition |
Bridge details
| Structure | Continuous concrete slab |
| Length | about 103 ft |
| Location | 077341306 |
| NBI structure number | 000000000100321 |
| Condition class | Good |
| Traffic status (item 41) | Open, no restriction |
| Last inspection (item 90) | March 2024 |
| Inspection interval (item 91) | 48 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 Cass County
| Bridge | Built | Vehicles/day | Condition |
|---|---|---|---|
| I-80 over Camp Creek | 1965 | 23,500 | Fair |
| I-80 over Drainage Ditch | 1959 | 23,000 | Fair |
| I-80 over Stream | 1965 | 22,400 | Fair |
| I 80 EB over Indian Creek | 2013 | 11,800 | Good |
| I 80 WB over Indian Creek | 2014 | 11,800 | Good |
| EB I-80 over 570TH St | 1966 | 11,750 | Fair |
All bridges nearby: Cass County, IA bridge conditions · every bridge in Cass County · Iowa bridges.
Background: how bridge ratings work · what "poor" and "structurally deficient" actually mean · how often bridges are inspected.