Pk 658(WANATA) over Little Sioux River
Clay County, Iowa · rated Good in the 2025 National Bridge Inventory
United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled
- Pk 658(WANATA) over Little Sioux River in Clay County, Iowa, is rated in good condition in the 2025 National Bridge Inventory (as of ).
- Its lowest-rated component is the superstructure, rated 7 (good condition) on the 0-9 scale.
- It was built in 1972, making it 53 years old at the 2025 inventory.
- It carries about 58 vehicles a day (traffic count year 2022).
- It is one of 58 of the 154 inventoried bridges in Clay County rated good (37.7%); 16 (10.4%) 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 September 2024, on a 24-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 → (42.9144, -95.33953)
Component ratings
| Component | Rating (2024) | Rating (2025) | FHWA scale meaning |
|---|---|---|---|
| Deck | 8 | 8 | Very good condition |
| Superstructure | 7 | 7 | Good condition |
| Substructure | 7 | 7 | Good condition |
Bridge details
| Structure | Prestressed concrete stringer or multi-beam girder |
| Length | about 207 ft |
| Location | In Wanata State Park |
| NBI structure number | 000000000699240 |
| Condition class | Good |
| Traffic status (item 41) | Open, no restriction |
| Last inspection (item 90) | September 2024 |
| Inspection interval (item 91) | 24 months |
| Scour (item 113) | 5: foundations stable, scour within the limits of the footing or piles |
Source: FHWA National Bridge Inventory, 2025 data as reported by the Iowa department of transportation.
Busiest bridges in Clay County
| Bridge | Built | Vehicles/day | Condition |
|---|---|---|---|
| US 18 & 71 over Little Sioux River | 2006 | 16,900 | Good |
| US 71 over Br of Little Meadow Crk | 1990 | 11,400 | Fair |
| US 71 over Prairie Creek | 2017 | 4,770 | Good |
| US 18 over Lost Island Outlet | 1931 | 4,270 | Fair |
| US 18 over Drainage Ditch | 1965 | 4,270 | Fair |
| US 18 over Little Sioux River | 2010 | 4,170 | Good |
All bridges nearby: Clay County, IA bridge conditions · every bridge in Clay County · Iowa bridges.
Background: how bridge ratings work · what "poor" and "structurally deficient" actually mean · how often bridges are inspected.