US Bridges

SR 18 Ramp over Holder CR

Fair

King County, Washington · 0.2 N JCT SR 18 · Structure no. 0006403A0000000

Built
1960
65 years old
Condition
Fair
inspected March 2024
Type
Slab
Concrete Continuous
Length
68 ft
3 main spans
Daily traffic
5,021
2023 count
Owner
State
State Highway Agency

About this bridge

SR 18 Ramp over Holder CR is a concrete continuous slab carrying SR 18 Ramp over Holder CR in King County, Washington. It was built in 1960, so it is 65 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 5,021 vehicles a day, roughly 5% of them trucks, projected to reach 7,362 by 2039. The structure is 68 ft (20.7 m) long and 52 ft wide. If it were closed, the detour would be 98.8 mi (159 km).

Location

Open in Google Maps
CarriesSR 18 Ramp
CrossesHolder CR
Location0.2 N JCT SR 18
RouteState Highway 18
CountyKing County
StateWashington
Coordinates47.43698, -121.97772
Functional classRural Principal Arterial - Other

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 protection6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionMarch 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourScour critical; foundations unstable for calculated scour conditions
Structural evaluation7: Better than present minimum criteria
Deck geometry9: Superior to present desirable criteria
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating40.7 US tons
Inventory rating31.4 US tons

Structure

Structure typeSlab
MaterialConcrete Continuous
DeckConcrete, cast-in-place
Main spans3
Design loadHS 20
Structure length68 ft (20.7 m)
Longest span26 ft (7.9 m)
Deck width52 ft (15.9 m)
Roadway width48 ft (14.6 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic5,021 (2023)
Projected traffic7,362 by 2039
Trucks5%
Lanes on structure1
Traffic directionOne-way traffic
CarriesHighway
CrossesWaterway
Detour if closed98.8 mi (159 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerState Highway Agency
Maintained byState Highway Agency
Historic statusNot eligible for the National Register of Historic Places
Work proposedRehabilitation because of general structure deterioration or inadequate strength
Estimated improvement cost$1.6 million (2022 estimate)
NavigationNo navigation control on waterway

Frequently asked questions

When was SR 18 Ramp over Holder CR built?

It was built in 1960, making it 65 years old in 2025.

What condition is SR 18 Ramp over Holder CR 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 2024.

How much traffic does SR 18 Ramp over Holder CR carry?

About 5,021 vehicles per day (2023 count), of which roughly 5% are trucks.

How long is SR 18 Ramp over Holder CR?

The structure is 68 ft (20.7 m) long with a longest span of 26 ft (7.9 m) and a deck 52 ft wide.

Who owns SR 18 Ramp over Holder CR?

It is owned by the State Highway Agency.