I-5 over Capitol Lake
GoodThurston County, Washington · 0.5 N JCT US 101 · Structure no. 0005090A0000000
- Built
- 1956
- 69 years old, rebuilt 1986
- Condition
- Good
- inspected November 2023
- Type
- Box Beam or Girders - Multiple
- Concrete Continuous
- Length
- 392 ft
- 4 main spans
- Daily traffic
- 49,410
- 2023 count
- Owner
- State
- State Highway Agency
About this bridge
I-5 over Capitol Lake is a concrete continuous box beam or girders - multiple carrying I-5 over Capitol Lake in Thurston County, Washington. It was built in 1956 and reconstructed in 1986, so it is 69 years old, older than the Washington average of 49.8 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 49,410 vehicles a day, roughly 13% of them trucks, projected to reach 76,937 by 2039. The structure is 392 ft (119.5 m) long and 210 ft wide. If it were closed, the detour would be 8.1 mi (13 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. |
| Channel and channel protection | 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 I-5 over Capitol Lake built?
It was built in 1956, making it 69 years old in 2025. It was reconstructed in 1986.
What condition is I-5 over Capitol Lake 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 November 2023.
How much traffic does I-5 over Capitol Lake carry?
About 49,410 vehicles per day (2023 count), of which roughly 13% are trucks.
How long is I-5 over Capitol Lake?
The structure is 392 ft (119.5 m) long with a longest span of 110 ft (33.5 m) and a deck 210 ft wide.
Who owns I-5 over Capitol Lake?
It is owned by the State Highway Agency.