N Main ST over Knob CR
PoorClosed to trafficIron County, Missouri · S 31 T 34 N R 4 E · Structure no. 13640
- Built
- 1972
- 53 years old
- Condition
- Poor
- inspected February 2025
- Type
- Stringer/Multi-beam or Girder
- Steel
- Length
- 60 ft
- 2 main spans
- Daily traffic
- 200
- 2023 count
- Owner
- City
- City or Municipal Highway Agency
About this bridge
N Main ST over Knob CR is a steel stringer/multi-beam or girder carrying N Main ST over Knob CR in Iron County, Missouri. It was built in 1972, so it is 53 years old, older than the Missouri average of 45.1 years.
The most recent inspection reported to the Federal Highway Administration rates it in poor condition with a lowest component rating of 2 out of 9. The lowest-rated primary component is rated 4 or below, indicating advanced deterioration. Poor does not mean unsafe; such bridges are inspected more often and may carry load restrictions. Its operating status is: closed to all traffic.
It carries about 200 vehicles a day, roughly 10% of them trucks, projected to reach 240 by 2043. The structure is 60 ft (18.3 m) long and 20 ft wide. If it were closed, the detour would be 1.9 mi (3 km).
Location
Open in Google MapsCondition and inspection
The lowest-rated primary component is rated 4 or below, indicating advanced deterioration. Poor does not mean unsafe; such bridges are inspected more often and may carry load restrictions.
| Component | Rating | Meaning |
|---|---|---|
| Deck | 4 Poor | Advanced section loss, deterioration, spalling or scour. |
| Superstructure | 2 Critical | Advanced deterioration of primary structural elements. Bridge may be closed until corrective action is taken. |
| Substructure | 3 Serious | Loss of section, deterioration, spalling or scour have seriously affected primary structural components. |
| Channel and channel protection | 7 Good | Some minor problems. |
Structure
Traffic and service
Ownership and planned work
Frequently asked questions
When was N Main ST over Knob CR built?
It was built in 1972, making it 53 years old in 2025.
What condition is N Main ST over Knob CR in?
The National Bridge Inventory rates it in poor condition. The lowest-rated primary component is rated 4 or below, indicating advanced deterioration. Poor does not mean unsafe; such bridges are inspected more often and may carry load restrictions. The last reported inspection was in February 2025.
How much traffic does N Main ST over Knob CR carry?
About 200 vehicles per day (2023 count), of which roughly 10% are trucks.
How long is N Main ST over Knob CR?
The structure is 60 ft (18.3 m) long with a longest span of 29 ft (8.8 m) and a deck 20 ft wide.
Who owns N Main ST over Knob CR?
It is owned by the City or Municipal Highway Agency.