US Bridges

NB I-5 Ramp over Dillenbaugh Creek

Good

Lewis County, Washington · 3.8 N JCT SR 508 · Structure no. 0017324B0000000

Built
2009
16 years old
Condition
Good
inspected May 2023
Type
Culvert
Concrete
Length
26 ft
1 main span
Daily traffic
2,626
2023 count
Owner
State
State Highway Agency

About this bridge

NB I-5 Ramp over Dillenbaugh Creek is a concrete culvert carrying NB I-5 Ramp over Dillenbaugh Creek in Lewis County, Washington. It was built in 2009, so it is 16 years old, younger 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 8 out of 9. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

It carries about 2,626 vehicles a day, roughly 13% of them trucks, projected to reach 3,543 by 2039. The structure is 26 ft (7.9 m) long. If it were closed, the detour would be 5 mi (8 km).

CarriesNB I-5 Ramp
CrossesDillenbaugh Creek
Location3.8 N JCT SR 508
RouteInterstate 5
Coordinates46.62756, -122.93392
Functional classUrban Principal Arterial - Interstate

Condition and inspection

Good

All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

ComponentRatingMeaning
Channel and channel protection7 GoodSome minor problems.
Culvert8 Very GoodNo problems noted.
Last inspectionMay 2023
Inspection intervalevery 48 months
Operating statusOpen, no restriction
ScourFoundations stable; scour within limits of footing or piles
Structural evaluation8: Equal to present desirable criteria
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating81 US tons
Inventory rating48.9 US tons

Structure

Structure typeCulvert
MaterialConcrete
DeckNot applicable
Main spans1
Design loadHS 25 or greater
Structure length26 ft (7.9 m)
Longest span26 ft (7.9 m)
Deck width0 ft (0 m)
Roadway width0 ft (0 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic2,626 (2023)
Projected traffic3,543 by 2039
Trucks13%
Lanes on structure2
Traffic directionOne-way traffic
CarriesHighway
CrossesWaterway
Detour if closed5 mi (8 km)
TollOn a free road
National Highway SystemYes

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$568,000 (2022 estimate)
NavigationNo navigation control on waterway

Frequently asked questions

When was NB I-5 Ramp over Dillenbaugh Creek built?

It was built in 2009, making it 16 years old in 2025.

What condition is NB I-5 Ramp over Dillenbaugh Creek 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 May 2023.

How much traffic does NB I-5 Ramp over Dillenbaugh Creek carry?

About 2,626 vehicles per day (2023 count), of which roughly 13% are trucks.

How long is NB I-5 Ramp over Dillenbaugh Creek?

The structure is 26 ft (7.9 m) long with a longest span of 26 ft (7.9 m).

Who owns NB I-5 Ramp over Dillenbaugh Creek?

It is owned by the State Highway Agency.