Mo 21 S over Butler Lk
FairSt. Louis County, Missouri · S 13 T 43 N R 5 E · Structure no. 29033
- Built
- 2002
- 23 years old
- Condition
- Fair
- inspected October 2024
- Type
- Stringer/Multi-beam or Girder
- Steel Continuous
- Length
- 797 ft
- 8 main spans
- Daily traffic
- 18,038
- 2024 count
- Owner
- State
- State Highway Agency
About this bridge
Mo 21 S over Butler Lk is a steel continuous stringer/multi-beam or girder carrying Mo 21 S over Butler Lk in St. Louis County, Missouri. It was built in 2002, so it is 23 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 18,038 vehicles a day, roughly 5% of them trucks, projected to reach 25,253 by 2044. The structure is 797 ft (243 m) long and 85 ft wide. If it were closed, the detour would be 3.1 mi (5 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 | 7 Good | Some minor problems. |
| Superstructure | 7 Good | Some minor problems. |
| Substructure | 6 Satisfactory | Structural elements show some minor deterioration. |
| Channel and channel protection | 8 Very Good | No problems noted. |
Structure
Traffic and service
Ownership and planned work
Frequently asked questions
When was Mo 21 S over Butler Lk built?
It was built in 2002, making it 23 years old in 2025.
What condition is Mo 21 S over Butler Lk 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 October 2024.
How much traffic does Mo 21 S over Butler Lk carry?
About 18,038 vehicles per day (2024 count), of which roughly 5% are trucks.
How long is Mo 21 S over Butler Lk?
The structure is 797 ft (243 m) long with a longest span of 105 ft (32 m) and a deck 85 ft wide.
Who owns Mo 21 S over Butler Lk?
It is owned by the State Highway Agency.