US Bridges

C308 Clark Lane over Malheur River

Good

Harney County, Oregon · 020 MI Van Drewsey RD 306 · Structure no. 25E15 C30800198

Built
1979
46 years old
Condition
Good
inspected September 2024
Type
Slab
Prestressed Concrete
Length
72 ft
1 main span
Daily traffic
85
2020 count
Owner
County
County Highway Agency

About this bridge

C308 Clark Lane over Malheur River is a prestressed concrete slab carrying C308 Clark Lane over Malheur River in Harney County, Oregon. It was built in 1979, so it is 46 years old, younger than the Oregon average of 49.9 years.

The most recent inspection reported to the Federal Highway Administration rates it in good condition with a lowest component rating of 7 out of 9. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

It carries about 85 vehicles a day, roughly 10% of them trucks, projected to reach 95 by 2025. The structure is 72 ft (21.9 m) long and 28 ft wide. If it were closed, the detour would be 4.3 mi (7 km).

CarriesC308 Clark Lane
CrossesMalheur River
Location020 MI Van Drewsey RD 306
RouteCounty Highway C0308
StateOregon
Coordinates43.85693, -118.54509
Functional classRural Major Collector

Condition and inspection

Good

All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

ComponentRatingMeaning
Deck7 GoodSome minor problems.
Superstructure7 GoodSome minor problems.
Substructure8 Very GoodNo problems noted.
Channel and channel protection7 GoodSome minor problems.
Last inspectionSeptember 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourScour critical; foundations unstable for calculated scour conditions
Structural evaluation7: Better than present minimum criteria
Deck geometry6: Equal to present minimum criteria
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating72 US tons
Inventory rating43 US tons

Structure

Structure typeSlab
MaterialPrestressed Concrete
DeckConcrete, precast panels
Main spans1
Design loadHS 20
Structure length72 ft (21.9 m)
Longest span71 ft (21.6 m)
Deck width28 ft (8.5 m)
Roadway width28 ft (8.4 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic85 (2020)
Projected traffic95 by 2025
Trucks10%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed4.3 mi (7 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 C308 Clark Lane over Malheur River built?

It was built in 1979, making it 46 years old in 2025.

What condition is C308 Clark Lane over Malheur River in?

The National Bridge Inventory rates it in good condition. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted. The last reported inspection was in September 2024.

How much traffic does C308 Clark Lane over Malheur River carry?

About 85 vehicles per day (2020 count), of which roughly 10% are trucks.

How long is C308 Clark Lane over Malheur River?

The structure is 72 ft (21.9 m) long with a longest span of 71 ft (21.6 m) and a deck 28 ft wide.

Who owns C308 Clark Lane over Malheur River?

It is owned by the County Highway Agency.