Il 4 & 15 over Kaskaskia Overflow
GoodSt. Clair County, Illinois · 0.6 M E JCT Il 4 · Structure no. 082027500000000
- Built
- 2009
- 16 years old
- Condition
- Good
- inspected March 2024
- Type
- Stringer/Multi-beam or Girder
- Steel Continuous
- Length
- 145 ft
- 3 main spans
- Daily traffic
- 3,600
- 2023 count
- Owner
- State
- State Highway Agency
About this bridge
Il 4 & 15 over Kaskaskia Overflow is a steel continuous stringer/multi-beam or girder carrying Il 4 & 15 over Kaskaskia Overflow in St. Clair County, Illinois. It was built in 2009, so it is 16 years old, younger than the Illinois average of 45.3 years.
The most recent inspection reported to the Federal Highway Administration rates it in good condition with a lowest component rating of 8 out of 9. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.
It carries about 3,600 vehicles a day, roughly 15% of them trucks, projected to reach 3,788 by 2046. The structure is 145 ft (44.3 m) long and 43 ft wide. If it were closed, the detour would be 39.1 mi (63 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 | 8 Very Good | No problems noted. |
| Superstructure | 8 Very Good | No problems noted. |
| Substructure | 8 Very Good | No problems noted. |
| Channel and channel protection | 8 Very Good | No problems noted. |
Structure
Traffic and service
Ownership and planned work
Frequently asked questions
When was Il 4 & 15 over Kaskaskia Overflow built?
It was built in 2009, making it 16 years old in 2025.
What condition is Il 4 & 15 over Kaskaskia Overflow 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 March 2024.
How much traffic does Il 4 & 15 over Kaskaskia Overflow carry?
About 3,600 vehicles per day (2023 count), of which roughly 15% are trucks.
How long is Il 4 & 15 over Kaskaskia Overflow?
The structure is 145 ft (44.3 m) long with a longest span of 59 ft (18 m) and a deck 43 ft wide.
Who owns Il 4 & 15 over Kaskaskia Overflow?
It is owned by the State Highway Agency.