US Bridges

SR 27 over Palouse River

Fair

Whitman County, Washington · 14.8 N JCT SR 270 · Structure no. 0002309A0000000

Built
1938
87 years old
Condition
Fair
inspected May 2023
Type
Girder and Floorbeam System
Steel
Length
130 ft
1 main span
Daily traffic
3,048
2023 count
Owner
State
State Highway Agency

About this bridge

SR 27 over Palouse River is a steel girder and floorbeam system carrying SR 27 over Palouse River in Whitman County, Washington. It was built in 1938, so it is 87 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 3,048 vehicles a day, roughly 4% of them trucks, projected to reach 3,607 by 2039. The structure is 130 ft (39.5 m) long and 38 ft wide. If it were closed, the detour would be 1.2 mi (2 km).

Location

Open in Google Maps
CarriesSR 27
CrossesPalouse River
Location14.8 N JCT SR 270
RouteState Highway 27
CountyWhitman County
StateWashington
Coordinates46.90897, -117.07664
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 inspectionMay 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour within limits of footing or piles
Structural evaluation6: Equal to present minimum criteria
Deck geometry2: Basically intolerable, requiring high priority of replacement
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating61.9 US tons
Inventory rating37 US tons

Structure

Structure typeGirder and Floorbeam System
MaterialSteel
DeckConcrete, cast-in-place
Main spans1 (+2 approach)
Design loadH 15
Structure length130 ft (39.5 m)
Longest span95 ft (29.1 m)
Deck width38 ft (11.5 m)
Roadway width24 ft (7.3 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic3,048 (2023)
Projected traffic3,607 by 2039
Trucks4%
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 statusNot eligible for the National Register of Historic Places
Work proposedRehabilitation because of general structure deterioration or inadequate strength
Estimated improvement cost$1.8 million (2022 estimate)
NavigationNo navigation control on waterway

Frequently asked questions

When was SR 27 over Palouse River built?

It was built in 1938, making it 87 years old in 2025.

What condition is SR 27 over Palouse 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 May 2023.

How much traffic does SR 27 over Palouse River carry?

About 3,048 vehicles per day (2023 count), of which roughly 4% are trucks.

How long is SR 27 over Palouse River?

The structure is 130 ft (39.5 m) long with a longest span of 95 ft (29.1 m) and a deck 38 ft wide.

Who owns SR 27 over Palouse River?

It is owned by the State Highway Agency.