US Bridges

C140 Best Lane over Silver Creek

FairPosted for load

Harney County, Oregon · 079 MI US 20 · Structure no. 25A10 C14000794

Built
1978
47 years old
Condition
Fair
inspected September 2024
Type
Stringer/Multi-beam or Girder
Wood or Timber
Length
25 ft
1 main span
Daily traffic
48
2020 count
Owner
County
County Highway Agency

About this bridge

C140 Best Lane over Silver Creek is a wood or timber stringer/multi-beam or girder carrying C140 Best Lane over Silver Creek in Harney County, Oregon. It was built in 1978, so it is 47 years old, younger than the Oregon average of 49.9 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. Its operating status is: posted for load restriction.

It carries about 48 vehicles a day, roughly 10% of them trucks, projected to reach 53 by 2025. The structure is 25 ft (7.6 m) long and 24 ft wide. If it were closed, the detour would be 21.7 mi (35 km).

Location

Open in Google Maps
CarriesC140 Best Lane
CrossesSilver Creek
Location079 MI US 20
RouteCounty Highway C0140
CountyHarney County
StateOregon
Coordinates43.59018, -119.61074
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.
Superstructure7 GoodSome minor problems.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Channel and channel protection7 GoodSome minor problems.
Last inspectionSeptember 2024
Inspection intervalevery 24 months
Operating statusPosted for load restriction
ScourUnknown foundation; not evaluated for scour
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 adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating26.1 US tons
Inventory rating20 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialWood or Timber
DeckWood or timber
Main spans1
Design loadH 15
Structure length25 ft (7.6 m)
Longest span22 ft (6.7 m)
Deck width24 ft (7.3 m)
Roadway width23 ft (7 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic48 (2020)
Projected traffic53 by 2025
Trucks10%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed21.7 mi (35 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerCounty Highway Agency
Maintained byCounty Highway Agency
Historic statusNot eligible for the National Register of Historic Places
Work proposedNone recorded
Estimated improvement cost—
NavigationNo navigation control on waterway

Frequently asked questions

When was C140 Best Lane over Silver Creek built?

It was built in 1978, making it 47 years old in 2025.

What condition is C140 Best Lane over Silver 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 September 2024.

How much traffic does C140 Best Lane over Silver Creek carry?

About 48 vehicles per day (2020 count), of which roughly 10% are trucks.

How long is C140 Best Lane over Silver Creek?

The structure is 25 ft (7.6 m) long with a longest span of 22 ft (6.7 m) and a deck 24 ft wide.

Who owns C140 Best Lane over Silver Creek?

It is owned by the County Highway Agency.