US Bridges

SR 155 over Columbia River

Fair

Douglas County, Washington · 0.2 N Grant CO · Structure no. 000000JJ0000000

Built
1935
90 years old
Condition
Fair
inspected October 2023
Type
Truss - Thru
Steel Continuous
Length
1,089 ft
3 main spans
Daily traffic
4,923
2023 count
Owner
State
State Highway Agency

About this bridge

SR 155 over Columbia River is a steel continuous truss - thru carrying SR 155 over Columbia River in Douglas County, Washington. It was built in 1935, so it is 90 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 4,923 vehicles a day, roughly 6% of them trucks, projected to reach 6,211 by 2039. The structure is 1,089 ft (331.9 m) long and 22 ft wide. If it were closed, the detour would be 1.2 mi (2 km).

Location

Open in Google Maps
CarriesSR 155
CrossesColumbia River
Location0.2 N Grant CO
RouteState Highway 155
CountyDouglas County
StateWashington
Coordinates47.96539, -118.98232
Functional classRural Minor Arterial

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 protection8 Very GoodNo problems noted.
Last inspectionOctober 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation5: Somewhat better than minimum adequacy to tolerate being left in place as is
Deck geometry2: Basically intolerable, requiring high priority of replacement
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment6: Equal to present minimum criteria
Operating rating41 US tons
Inventory rating24 US tons

Structure

Structure typeTruss - Thru
MaterialSteel Continuous
DeckOpen grating
Main spans3 (+4 approach)
Design loadH 15
Structure length1,089 ft (331.9 m)
Longest span550 ft (167.6 m)
Deck width22 ft (6.7 m)
Roadway width20 ft (6.2 m)
Vertical clearance over deck15 ft (4.5 m)

Traffic and service

Average daily traffic4,923 (2023)
Projected traffic6,211 by 2039
Trucks6%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway and pedestrian
CrossesWaterway
Detour if closed1.2 mi (2 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerState Highway Agency
Maintained byState Highway Agency
Historic statusListed on the National Register of Historic Places
Work proposedRehabilitation because of general structure deterioration or inadequate strength
Estimated improvement cost$21.7 million (2022 estimate)
NavigationNavigation control on waterway (bridge permit required)

Frequently asked questions

When was SR 155 over Columbia River built?

It was built in 1935, making it 90 years old in 2025.

What condition is SR 155 over Columbia River 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 October 2023.

How much traffic does SR 155 over Columbia River carry?

About 4,923 vehicles per day (2023 count), of which roughly 6% are trucks.

How long is SR 155 over Columbia River?

The structure is 1,089 ft (331.9 m) long with a longest span of 550 ft (167.6 m) and a deck 22 ft wide.

Who owns SR 155 over Columbia River?

It is owned by the State Highway Agency.