US Bridges

Road over South Fork Manastash CR

Fair

Kittitas County, Washington · No Data Entered · Structure no. 061703000001494

Built
1975
50 years old
Condition
Fair
inspected June 2023
Type
Stringer/Multi-beam or Girder
Wood or Timber
Length
25 ft
1 main span
Daily traffic
100
1995 count
Owner
Federal
U.S. Forest Service

About this bridge

Road over South Fork Manastash CR is a wood or timber stringer/multi-beam or girder carrying Road over South Fork Manastash CR in Kittitas County, Washington. It was built in 1975, so it is 50 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 100 vehicles a day, roughly 10% of them trucks, projected to reach 150 by 2045. The structure is 25 ft (7.5 m) long and 16 ft wide. If it were closed, the detour would be 39.8 mi (64 km).

CarriesRoad
CrossesSouth Fork Manastash CR
LocationNo Data Entered
RouteFederal Lands Road 31000
Coordinates46.99361, -120.86694
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
Deck6 SatisfactoryStructural elements show some minor deterioration.
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 protection7 GoodSome minor problems.
Last inspectionJune 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; action required to protect exposed foundations
Structural evaluation5: Somewhat better than minimum adequacy to tolerate being left in place as is
Deck geometry6: Equal to present minimum criteria
Waterway adequacy7: Better than present minimum criteria
Approach roadway alignment6: Equal to present minimum criteria
Operating rating38.9 US tons
Inventory rating30 US tons

Structure

MaterialWood or Timber
DeckWood or timber
Main spans1
Design loadOther
Structure length25 ft (7.5 m)
Longest span23 ft (7 m)
Deck width16 ft (4.8 m)
Roadway width14 ft (4.3 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic100 (1995)
Projected traffic150 by 2045
Trucks10%
Lanes on structure1
Traffic directionOne-lane bridge for two-way traffic
CarriesHighway
CrossesWaterway
Detour if closed39.8 mi (64 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerU.S. Forest Service
Maintained byU.S. Forest Service
Historic statusHistorical significance not determinable at this time
Work proposedNone recorded
Estimated improvement cost—
NavigationNo navigation control on waterway

Frequently asked questions

When was Road over South Fork Manastash CR built?

It was built in 1975, making it 50 years old in 2025.

What condition is Road over South Fork Manastash CR 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 Road over South Fork Manastash CR carry?

About 100 vehicles per day (1995 count), of which roughly 10% are trucks.

How long is Road over South Fork Manastash CR?

The structure is 25 ft (7.5 m) long with a longest span of 23 ft (7 m) and a deck 16 ft wide.

Who owns Road over South Fork Manastash CR?

It is owned by the U.S. Forest Service.