US Bridges

I-5 over Drainage Ditch

Fair

Skagit County, Washington · 2.4 N JCT SR 11 · Structure no. 0007216C0000000

Built
1964
61 years old
Condition
Fair
inspected March 2023
Type
Slab
Concrete Continuous
Length
152 ft
5 main spans
Daily traffic
25,876
2023 count
Owner
State
State Highway Agency

About this bridge

I-5 over Drainage Ditch is a concrete continuous slab carrying I-5 over Drainage Ditch in Skagit County, Washington. It was built in 1964, so it is 61 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 152 ft (46.3 m) long and 42 ft wide. If it were closed, the detour would be 6.8 mi (11 km).

Location

Open in Google Maps
CarriesI-5
CrossesDrainage Ditch
Location2.4 N JCT SR 11
RouteInterstate 5
CountySkagit County
StateWashington
Coordinates48.51883, -122.34569
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
Deck6 SatisfactoryStructural elements show some minor deterioration.
Superstructure7 GoodSome minor problems.
Substructure7 GoodSome minor problems.
Channel and channel protection8 Very GoodNo problems noted.
Last inspectionMarch 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour within limits of footing or piles
Structural evaluation7: Better than present minimum criteria
Deck geometry6: Equal to present minimum criteria
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating41.8 US tons
Inventory rating32.2 US tons

Structure

Structure typeSlab
MaterialConcrete Continuous
DeckConcrete, cast-in-place
Main spans5
Design loadHS 20
Structure length152 ft (46.3 m)
Longest span34 ft (10.4 m)
Deck width42 ft (12.8 m)
Roadway width39 ft (11.9 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 closed6.8 mi (11 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$2.9 million (2022 estimate)
NavigationNo navigation control on waterway

Frequently asked questions

When was I-5 over Drainage Ditch built?

It was built in 1964, making it 61 years old in 2025.

What condition is I-5 over Drainage Ditch 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 March 2023.

How much traffic does I-5 over Drainage Ditch carry?

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

How long is I-5 over Drainage Ditch?

The structure is 152 ft (46.3 m) long with a longest span of 34 ft (10.4 m) and a deck 42 ft wide.

Who owns I-5 over Drainage Ditch?

It is owned by the State Highway Agency.