Mo 21 N over Rt Bb
GoodJefferson County, Missouri · S 33 T 41 N R 4 E · Structure no. 29597
- Built
- 2003
- 22 years old
- Condition
- Good
- inspected December 2024
- Type
- Stringer/Multi-beam or Girder
- Prestressed Concrete Continuous
- Length
- 170 ft
- 3 main spans
- Daily traffic
- 9,486
- 2024 count
- Owner
- State
- State Highway Agency
About this bridge
Mo 21 N over Rt Bb is a prestressed concrete continuous stringer/multi-beam or girder carrying Mo 21 N over Rt Bb in Jefferson County, Missouri. It was built in 2003, so it is 22 years old, younger than the Missouri average of 45.1 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 9,486 vehicles a day, roughly 8% of them trucks, projected to reach 17,549 by 2044. The structure is 170 ft (51.8 m) long and 41 ft wide. If it were closed, the detour would be 1.2 mi (2 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. |
Structure
Traffic and service
Ownership and planned work
Frequently asked questions
When was Mo 21 N over Rt Bb built?
It was built in 2003, making it 22 years old in 2025.
What condition is Mo 21 N over Rt Bb 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 December 2024.
How much traffic does Mo 21 N over Rt Bb carry?
About 9,486 vehicles per day (2024 count), of which roughly 8% are trucks.
How long is Mo 21 N over Rt Bb?
The structure is 170 ft (51.8 m) long with a longest span of 65 ft (19.8 m) and a deck 41 ft wide.
Who owns Mo 21 N over Rt Bb?
It is owned by the State Highway Agency.