US Bridges

County Road 938 over Mill Creek

Fair

Walla Walla County, Washington · 8 Miles West of Walla Wal · Structure no. 9550001P0000000

Built
1962
63 years old
Condition
Fair
inspected July 2024
Type
Tee Beam
Prestressed Concrete
Length
93 ft
2 main spans
Daily traffic
500
2019 count
Owner
Federal
National Park Service

About this bridge

County Road 938 over Mill Creek is a prestressed concrete tee beam carrying County Road 938 over Mill Creek in Walla Walla County, Washington. It was built in 1962, so it is 63 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 5 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 500 vehicles a day, roughly 1% of them trucks, projected to reach 800 by 2039. The structure is 93 ft (28.3 m) long and 32 ft wide. If it were closed, the detour would be 1.9 mi (3 km).

Location

Open in Google Maps
CarriesCounty Road 938
CrossesMill Creek
Location8 Miles West of Walla Wal
RouteFederal Lands Road 10
CountyWalla Walla County
StateWashington
Coordinates46.04186, -118.471
Functional classRural Local

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.
Substructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Channel and channel protection4 PoorAdvanced section loss, deterioration, spalling or scour.
Last inspectionJuly 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour within limits of footing or piles
Structural evaluation5: Somewhat better than minimum adequacy to tolerate being left in place as is
Deck geometry5: Somewhat better than minimum adequacy to tolerate being left in place as is
Waterway adequacy6: Equal to present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating45 US tons
Inventory rating27 US tons

Structure

Structure typeTee Beam
MaterialPrestressed Concrete
DeckConcrete, cast-in-place
Main spans2
Design loadHS 15
Structure length93 ft (28.3 m)
Longest span47 ft (14.3 m)
Deck width32 ft (9.8 m)
Roadway width26 ft (8 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic500 (2019)
Projected traffic800 by 2039
Trucks1%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed1.9 mi (3 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerNational Park Service
Maintained byNational Park Service
Historic statusNot eligible for the National Register of Historic Places
Work proposedRehabilitation because of general structure deterioration or inadequate strength
Estimated improvement cost$450,000 (2022 estimate)
NavigationNo navigation control on waterway

Frequently asked questions

When was County Road 938 over Mill Creek built?

It was built in 1962, making it 63 years old in 2025.

What condition is County Road 938 over Mill Creek 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 July 2024.

How much traffic does County Road 938 over Mill Creek carry?

About 500 vehicles per day (2019 count), of which roughly 1% are trucks.

How long is County Road 938 over Mill Creek?

The structure is 93 ft (28.3 m) long with a longest span of 47 ft (14.3 m) and a deck 32 ft wide.

Who owns County Road 938 over Mill Creek?

It is owned by the National Park Service.