US Bridges

I-5 over Samish River Pvt RD

Fair

Skagit County, Washington · 2.9 N JCT SR 11 · Structure no. 0007141B0000000

Built
1963
62 years old
Condition
Fair
inspected May 2024
Type
Slab
Concrete Continuous
Length
187 ft
5 main spans
Daily traffic
25,876
2023 count
Owner
State
State Highway Agency

About this bridge

I-5 over Samish River Pvt RD is a concrete continuous slab carrying I-5 over Samish River Pvt RD in Skagit County, Washington. It was built in 1963, so it is 62 years old, older than the Washington average of 49.8 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 25,876 vehicles a day, roughly 7% of them trucks, projected to reach 39,443 by 2039. The structure is 187 ft (57 m) long and 36 ft wide. If it were closed, the detour would be 1.2 mi (2 km).

CarriesI-5
CrossesSamish River Pvt RD
Location2.9 N JCT SR 11
RouteInterstate 5
Coordinates48.524, -122.34903
Functional classRural Principal Arterial - Interstate

Condition and inspection

Fair

The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound.

ComponentRatingMeaning
Deck7 GoodSome minor problems.
Superstructure6 SatisfactoryStructural elements show some minor deterioration.
Substructure7 GoodSome minor problems.
Channel and channel protection6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionMay 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation6: Equal to present minimum criteria
Deck geometry3: Basically intolerable, requiring high priority of corrective action
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating44.6 US tons
Inventory rating34.3 US tons

Structure

Structure typeSlab
MaterialConcrete Continuous
DeckConcrete, cast-in-place
Main spans5
Design loadHS 20
Structure length187 ft (57 m)
Longest span45 ft (13.8 m)
Deck width36 ft (10.9 m)
Roadway width33 ft (10.2 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic25,876 (2023)
Projected traffic39,443 by 2039
Trucks7%
Lanes on structure2
Traffic directionOne-way traffic
CarriesHighway
CrossesWaterway
Detour if closed1.2 mi (2 km)
TollOn a free road
National Highway SystemYes
Strategic Highway NetworkInterstate STRAHNET route

Ownership and planned work

OwnerState Highway Agency
Maintained byState Highway Agency
Historic statusHistorical significance not determinable at this time
Work proposedRehabilitation because of general structure deterioration or inadequate strength
Estimated improvement cost$3.1 million (2022 estimate)
NavigationNo navigation control on waterway

Frequently asked questions

When was I-5 over Samish River Pvt RD built?

It was built in 1963, making it 62 years old in 2025.

What condition is I-5 over Samish River Pvt RD 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 May 2024.

How much traffic does I-5 over Samish River Pvt RD carry?

About 25,876 vehicles per day (2023 count), of which roughly 7% are trucks.

How long is I-5 over Samish River Pvt RD?

The structure is 187 ft (57 m) long with a longest span of 45 ft (13.8 m) and a deck 36 ft wide.

Who owns I-5 over Samish River Pvt RD?

It is owned by the State Highway Agency.