NB I-35 over Drainage Ditch #29
Wright County, Iowa · rated Good in the 2025 National Bridge Inventory
United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled
- NB I-35 over Drainage Ditch #29 in Wright 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 1974, making it 51 years old at the 2025 inventory.
- It carries about 8,250 vehicles a day (traffic count year 2023).
- Its listed owner is the state highway agency.
- It is one of 61 of the 175 inventoried bridges in Wright County rated good (34.9%); 48 (27.4%) 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 January 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 → (42.58741, -93.531)
Component ratings
| Component | Rating (2024) | Rating (2025) | FHWA scale meaning |
|---|---|---|---|
| Deck | 7 | 7 | Good condition |
| Superstructure | 8 | 8 | Very good condition |
| Substructure | 7 | 7 | Good condition |
Bridge details
| Structure | Prestressed concrete stringer or multi-beam girder |
| Length | about 150 ft |
| Location | 1.3 mi N of jct SR C70 |
| NBI structure number | 000000000602590 |
| Condition class | Good |
| Traffic status (item 41) | Open, no restriction |
| Last inspection (item 90) | January 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 Wright County
| Bridge | Built | Vehicles/day | Condition |
|---|---|---|---|
| SB I-35 over Drainage Ditch #29 | 1974 | 8,250 | Fair |
| I 35 NB over Iowa River | 1974 | 8,250 | Good |
| SB I-35 over Iowa River | 1974 | 8,250 | Fair |
| Ia 3 over White Fox Creek | 1986 | 4,020 | Good |
| Ia 3 over Eagle Creek | 1932 | 3,450 | Fair |
| Ia 3 over Little Eagle Creek | 2016 | 3,450 | Good |
All bridges nearby: Wright County, IA bridge conditions · every bridge in Wright County · Iowa bridges.
Background: how bridge ratings work · what "poor" and "structurally deficient" actually mean · how often bridges are inspected.