320th ST over Three Mile Creek
GoodAdair County, Iowa · 1.2 MI East of P33 · Structure no. 000000000054711
- Built
- 2013
- 12 years old
- Condition
- Good
- inspected April 2024
- Type
- Stringer/Multi-beam or Girder
- Steel
- Length
- 70 ft
- 1 main span
- Daily traffic
- 21
- 2022 count
- Owner
- County
- County Highway Agency
About this bridge
320th ST over Three Mile Creek is a steel stringer/multi-beam or girder carrying 320th ST over Three Mile Creek in Adair County, Iowa. It was built in 2013, so it is 12 years old, younger than the Iowa average of 45.5 years.
The most recent inspection reported to the Federal Highway Administration rates it in good condition with a lowest component rating of 7 out of 9. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.
It carries about 21 vehicles a day, projected to reach 21 by 2043. The structure is 70 ft (21.3 m) long and 25 ft wide. If it were closed, the detour would be 3.7 mi (6 km).
Location
Open in Google MapsCondition and inspection
All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.
| Component | Rating | Meaning |
|---|---|---|
| Deck | 7 Good | Some minor problems. |
| Superstructure | 7 Good | Some minor problems. |
| Substructure | 7 Good | Some minor problems. |
| Channel and channel protection | 8 Very Good | No problems noted. |
Structure
Traffic and service
Ownership and planned work
Frequently asked questions
When was 320th ST over Three Mile Creek built?
It was built in 2013, making it 12 years old in 2025.
What condition is 320th ST over Three Mile Creek in?
The National Bridge Inventory rates it in good condition. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted. The last reported inspection was in April 2024.
How much traffic does 320th ST over Three Mile Creek carry?
About 21 vehicles per day (2022 count).
How long is 320th ST over Three Mile Creek?
The structure is 70 ft (21.3 m) long with a longest span of 69 ft (21 m) and a deck 25 ft wide.
Who owns 320th ST over Three Mile Creek?
It is owned by the County Highway Agency.