Glenn Highway over Knik Riv. Overflow S.B.
FairMatanuska-Susitna Borough, Alaska · Mile Point 29.6 · Structure no. 1887
- Built
- 1993
- 32 years old
- Condition
- Fair
- inspected July 2023
- Type
- Tee Beam
- Prestressed Concrete
- Length
- 250 ft
- 2 main spans
- Daily traffic
- 13,300
- 2020 count
- Owner
- State
- State Highway Agency
About this bridge
Glenn Highway over Knik Riv. Overflow S.B. is a prestressed concrete tee beam carrying Glenn Highway over Knik Riv. Overflow S.B. in Matanuska-Susitna Borough, Alaska. It was built in 1993, so it is 32 years old, younger than the Alaska average of 35.9 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 13,300 vehicles a day, roughly 8% of them trucks, projected to reach 15,400 by 2039. The structure is 250 ft (76.2 m) long and 40 ft wide. If it were closed, the detour would be 28 mi (45 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 | 6 Satisfactory | Structural elements show some minor deterioration. |
| Superstructure | 7 Good | Some minor problems. |
| Substructure | 6 Satisfactory | Structural elements show some minor deterioration. |
| Channel and channel protection | 9 Excellent | No problems noted. |
Structure
Traffic and service
Ownership and planned work
Frequently asked questions
When was Glenn Highway over Knik Riv. Overflow S.B. built?
It was built in 1993, making it 32 years old in 2025.
What condition is Glenn Highway over Knik Riv. Overflow S.B. 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 July 2023.
How much traffic does Glenn Highway over Knik Riv. Overflow S.B. carry?
About 13,300 vehicles per day (2020 count), of which roughly 8% are trucks.
How long is Glenn Highway over Knik Riv. Overflow S.B.?
The structure is 250 ft (76.2 m) long with a longest span of 123 ft (37.5 m) and a deck 40 ft wide.
Who owns Glenn Highway over Knik Riv. Overflow S.B.?
It is owned by the State Highway Agency.