Ia 183 over Drainage Ditch
Harrison County, Iowa · rated Good in the 2025 National Bridge Inventory
United States Bridge Conditions2025 National Bridge Inventory, FHWACompiled
- Ia 183 over Drainage Ditch in Harrison County, Iowa, is rated in good condition in the 2025 National Bridge Inventory (as of ).
- Its lowest-rated component is the culvert, rated 8 (very good condition) on the 0-9 scale.
- It was built in 2008, making it 17 years old at the 2025 inventory.
- It carries about 580 vehicles a day (traffic count year 2022).
- Its listed owner is the state highway agency.
- It is one of 61 of the 222 inventoried bridges in Harrison County rated good (27.5%); 41 (18.5%) 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 December 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 → (41.85748, -95.91544)
Component ratings
| Component | Rating (2024) | Rating (2025) | FHWA scale meaning |
|---|---|---|---|
| Culvert | 8 | 8 | Very good condition |
Bridge details
| Structure | Continuous concrete culvert |
| Length | about 24 ft |
| Location | 1.9 Mi. N of N Jct SR F20 |
| NBI structure number | 000000000027971 |
| Condition class | Good |
| Traffic status (item 41) | Open, no restriction |
| Last inspection (item 90) | December 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 Harrison County
| Bridge | Built | Vehicles/day | Condition |
|---|---|---|---|
| US 30 over Willow Creek | 1972 | 10,300 | Fair |
| US 30 over UPRR | 1998 | 10,300 | Good |
| NB I-29 over Boyer River | 1958 | 10,050 | Fair |
| SB I-29 over Boyer River | 1958 | 10,050 | Fair |
| SB I-29 over over UP RR | 1967 | 7,750 | Fair |
| NB I-29 over Allen Creek | 1967 | 7,750 | Fair |
All bridges nearby: Harrison County, IA bridge conditions · every bridge in Harrison County · Iowa bridges.
Background: how bridge ratings work · what "poor" and "structurally deficient" actually mean · how often bridges are inspected.