Mo 231 S over Is 255
FairSt. Louis County, Missouri · S 1 T 43 N R 6 E · Structure no. 31869
- Built
- 2007
- 18 years old
- Condition
- Fair
- inspected July 2024
- Type
- Stringer/Multi-beam or Girder
- Steel Continuous
- Length
- 240 ft
- 2 main spans
- Daily traffic
- 41,695
- 2024 count
- Owner
- State
- State Highway Agency
About this bridge
Mo 231 S over Is 255 is a steel continuous stringer/multi-beam or girder carrying Mo 231 S over Is 255 in St. Louis County, Missouri. It was built in 2007, so it is 18 years old, younger than the Missouri average of 45.1 years.
The most recent inspection reported to the Federal Highway Administration rates it in fair condition with a lowest component rating of 6 out of 9. The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound.
It carries about 41,695 vehicles a day, roughly 4% of them trucks, projected to reach 58,373 by 2044. The structure is 240 ft (73.2 m) long and 103 ft wide. If it were closed, the detour would be 1.2 mi (2 km).
Location
Open in Google MapsCondition and inspection
The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound.
| Component | Rating | Meaning |
|---|---|---|
| Deck | 6 Satisfactory | Structural elements show some minor deterioration. |
| Superstructure | 7 Good | Some minor problems. |
| Substructure | 7 Good | Some minor problems. |
Structure
Traffic and service
Ownership and planned work
Frequently asked questions
When was Mo 231 S over Is 255 built?
It was built in 2007, making it 18 years old in 2025.
What condition is Mo 231 S over Is 255 in?
The National Bridge Inventory rates it in fair condition. The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound. The last reported inspection was in July 2024.
How much traffic does Mo 231 S over Is 255 carry?
About 41,695 vehicles per day (2024 count), of which roughly 4% are trucks.
How long is Mo 231 S over Is 255?
The structure is 240 ft (73.2 m) long with a longest span of 120 ft (36.6 m) and a deck 103 ft wide.
Who owns Mo 231 S over Is 255?
It is owned by the State Highway Agency.