Il 171 & 79 ST EB over US 12 20 45 Mannheim
PoorCook County, Illinois · 0.1 M SW US 45 · Structure no. 016051800000000
- Built
- 1959
- 66 years old, rebuilt 1998
- Condition
- Poor
- inspected September 2023
- Type
- Stringer/Multi-beam or Girder
- Steel
- Length
- 180 ft
- 3 main spans
- Daily traffic
- 17,300
- 2022 count
- Owner
- State
- State Highway Agency
About this bridge
Il 171 & 79 ST EB over US 12 20 45 Mannheim is a steel stringer/multi-beam or girder carrying Il 171 & 79 ST EB over US 12 20 45 Mannheim in Cook County, Illinois. It was built in 1959 and reconstructed in 1998, so it is 66 years old, older than the Illinois average of 45.3 years.
The most recent inspection reported to the Federal Highway Administration rates it in poor condition with a lowest component rating of 4 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.
It carries about 17,300 vehicles a day, roughly 22% of them trucks, projected to reach 23,129 by 2046. The structure is 180 ft (54.8 m) long and 36 ft wide.
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 | 5 Fair | All primary structural elements are sound but may have minor section loss, cracking, spalling or scour. |
| Substructure | 5 Fair | All primary structural elements are sound but may have minor section loss, cracking, spalling or scour. |
Structure
Traffic and service
Ownership and planned work
Frequently asked questions
When was Il 171 & 79 ST EB over US 12 20 45 Mannheim built?
It was built in 1959, making it 66 years old in 2025. It was reconstructed in 1998.
What condition is Il 171 & 79 ST EB over US 12 20 45 Mannheim 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 September 2023.
How much traffic does Il 171 & 79 ST EB over US 12 20 45 Mannheim carry?
About 17,300 vehicles per day (2022 count), of which roughly 22% are trucks.
How long is Il 171 & 79 ST EB over US 12 20 45 Mannheim?
The structure is 180 ft (54.8 m) long with a longest span of 65 ft (19.8 m) and a deck 36 ft wide.
Who owns Il 171 & 79 ST EB over US 12 20 45 Mannheim?
It is owned by the State Highway Agency.