US Bridges

SR 231 over Spokane River

Fair

Lincoln County, Washington · 13.6 N JCT US 2 · Structure no. 0003558A0000000

Built
1949
76 years old
Condition
Fair
inspected October 2024
Type
Arch - Deck
Concrete
Length
486 ft
1 main span
Daily traffic
1,110
2023 count
Owner
State
State Highway Agency

About this bridge

SR 231 over Spokane River is a concrete arch - deck carrying SR 231 over Spokane River in Lincoln County, Washington. It was built in 1949, so it is 76 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 1,110 vehicles a day, roughly 12% of them trucks, projected to reach 1,222 by 2039. The structure is 486 ft (148.1 m) long and 31 ft wide. If it were closed, the detour would be 98.8 mi (159 km).

Location

Open in Google Maps
CarriesSR 231
CrossesSpokane River
Location13.6 N JCT US 2
RouteState Highway 231
CountyLincoln County
StateWashington
Coordinates47.83844, -117.85264
Functional classRural Major Collector

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.
Superstructure6 SatisfactoryStructural elements show some minor deterioration.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Channel and channel protection8 Very GoodNo problems noted.
Last inspectionOctober 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations on dry land well above flood water elevations
Structural evaluation3: Basically intolerable, requiring high priority of corrective action
Deck geometry4: Meets minimum tolerable limits to be left in place as is
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment6: Equal to present minimum criteria
Operating rating17.5 US tons
Inventory rating13.6 US tons

Structure

Structure typeArch - Deck
MaterialConcrete
DeckConcrete, cast-in-place
Main spans1 (+7 approach)
Design loadH 15
Structure length486 ft (148.1 m)
Longest span200 ft (61 m)
Deck width31 ft (9.5 m)
Roadway width24 ft (7.3 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic1,110 (2023)
Projected traffic1,222 by 2039
Trucks12%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway and pedestrian
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 statusListed on the National Register of Historic Places
Work proposedRehabilitation because of general structure deterioration or inadequate strength
Estimated improvement cost$6.5 million (2022 estimate)
NavigationNo navigation control on waterway

Frequently asked questions

When was SR 231 over Spokane River built?

It was built in 1949, making it 76 years old in 2025.

What condition is SR 231 over Spokane 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 2024.

How much traffic does SR 231 over Spokane River carry?

About 1,110 vehicles per day (2023 count), of which roughly 12% are trucks.

How long is SR 231 over Spokane River?

The structure is 486 ft (148.1 m) long with a longest span of 200 ft (61 m) and a deck 31 ft wide.

Who owns SR 231 over Spokane River?

It is owned by the State Highway Agency.