US Bridges

SR 10 over Terrain

Fair

Kittitas County, Washington · 2.0 E JCT SR 970 · Structure no. 0002222A0000000

Built
1937
88 years old, rebuilt 2012
Condition
Fair
inspected June 2023
Type
Stringer/Multi-beam or Girder
Steel
Length
430 ft
15 main spans
Daily traffic
1,338
2023 count
Owner
State
State Highway Agency

About this bridge

SR 10 over Terrain is a steel stringer/multi-beam or girder carrying SR 10 over Terrain in Kittitas County, Washington. It was built in 1937 and reconstructed in 2012, so it is 88 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 1,338 vehicles a day, roughly 13% of them trucks, projected to reach 1,769 by 2039. The structure is 430 ft (131.1 m) long and 32 ft wide. If it were closed, the detour would be 21.1 mi (34 km).

Location

Open in Google Maps
CarriesSR 10
CrossesTerrain
Location2.0 E JCT SR 970
RouteState Highway 10
CountyKittitas County
StateWashington
Coordinates47.16562, -120.81905
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
Deck8 Very GoodNo problems noted.
Superstructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Substructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Last inspectionJune 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourBridge not over waterway
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
Approach roadway alignment6: Equal to present minimum criteria
Operating rating56 US tons
Inventory rating33 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialSteel
DeckConcrete, cast-in-place
Main spans15
Design loadH 15
Structure length430 ft (131.1 m)
Longest span33 ft (10.1 m)
Deck width32 ft (9.7 m)
Roadway width29 ft (8.7 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic1,338 (2023)
Projected traffic1,769 by 2039
Trucks13%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesOther
Detour if closed21.1 mi (34 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$6.3 million (2022 estimate)
NavigationNot applicable (no waterway)

Frequently asked questions

When was SR 10 over Terrain built?

It was built in 1937, making it 88 years old in 2025. It was reconstructed in 2012.

What condition is SR 10 over Terrain 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 June 2023.

How much traffic does SR 10 over Terrain carry?

About 1,338 vehicles per day (2023 count), of which roughly 13% are trucks.

How long is SR 10 over Terrain?

The structure is 430 ft (131.1 m) long with a longest span of 33 ft (10.1 m) and a deck 32 ft wide.

Who owns SR 10 over Terrain?

It is owned by the State Highway Agency.