US 18 over Rock River
GoodSioux County, Iowa · 0.3 Mi. W of JCT SR K24 · Structure no. 000000000048231
- Built
- 2002
- 23 years old
- Condition
- Good
- inspected June 2024
- Type
- Stringer/Multi-beam or Girder
- Prestressed Concrete
- Length
- 420 ft
- 4 main spans
- Daily traffic
- 3,160
- 2023 count
- Owner
- State
- State Highway Agency
About this bridge
US 18 over Rock River is a prestressed concrete stringer/multi-beam or girder carrying US 18 over Rock River in Sioux County, Iowa. It was built in 2002, so it is 23 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 3,160 vehicles a day, roughly 19% of them trucks, projected to reach 3,160 by 2044. The structure is 420 ft (128 m) long and 43 ft wide. If it were closed, the detour would be 8.7 mi (14 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 | 8 Very Good | No problems noted. |
| Substructure | 7 Good | Some minor problems. |
| Channel and channel protection | 7 Good | Some minor problems. |
Structure
Traffic and service
Ownership and planned work
Frequently asked questions
When was US 18 over Rock River built?
It was built in 2002, making it 23 years old in 2025.
What condition is US 18 over Rock River 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 June 2024.
How much traffic does US 18 over Rock River carry?
About 3,160 vehicles per day (2023 count), of which roughly 19% are trucks.
How long is US 18 over Rock River?
The structure is 420 ft (128 m) long with a longest span of 122 ft (37.2 m) and a deck 43 ft wide.
Who owns US 18 over Rock River?
It is owned by the State Highway Agency.