US Bridges

Middle Fork Road over M.Fk.Weiser River

Fair

Adams County, Idaho · 9.3 W 5.2 S Donnelly · Structure no. 000000000026538

Built
1960
65 years old
Condition
Fair
inspected August 2023
Type
Stringer/Multi-beam or Girder
Concrete
Length
36 ft
1 main span
Daily traffic
70
2023 count
Owner
County
County Highway Agency

About this bridge

Middle Fork Road over M.Fk.Weiser River is a concrete stringer/multi-beam or girder carrying Middle Fork Road over M.Fk.Weiser River in Adams County, Idaho. It was built in 1960, so it is 65 years old, older than the Idaho average of 45.3 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.

It carries about 70 vehicles a day, roughly 40% of them trucks, projected to reach 105 by 2042. The structure is 36 ft (11 m) long and 27 ft wide. If it were closed, the detour would be 29.8 mi (48 km).

Location

Open in Google Maps
CarriesMiddle Fork Road
CrossesM.Fk.Weiser River
Location9.3 W 5.2 S Donnelly
RouteCounty Highway 0
CountyAdams County
StateIdaho
Coordinates44.65156, -116.27011
Functional classRural Minor 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
Deck6 SatisfactoryStructural elements show some minor deterioration.
Superstructure7 GoodSome minor problems.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Channel and channel protection7 GoodSome minor problems.
Last inspectionAugust 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; action required to protect exposed foundations
Structural evaluation6: Equal to present minimum criteria
Waterway adequacy9: Superior to present desirable criteria
Approach roadway alignment7: Better than present minimum criteria
Operating rating80 US tons
Inventory rating48 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialConcrete
DeckConcrete, cast-in-place
Main spans1
Design loadHS 20
Structure length36 ft (11 m)
Longest span35 ft (10.7 m)
Deck width27 ft (8.1 m)
Roadway width24 ft (7.3 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic70 (2023)
Projected traffic105 by 2042
Trucks40%
Lanes on structure2
Traffic directionOne-lane bridge for two-way traffic
CarriesHighway
CrossesWaterway
Detour if closed29.8 mi (48 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerCounty Highway Agency
Maintained byCounty Highway Agency
Historic statusHistorical significance not determinable at this time
Work proposedNone recorded
Estimated improvement cost—
NavigationNo navigation control on waterway

Frequently asked questions

When was Middle Fork Road over M.Fk.Weiser River built?

It was built in 1960, making it 65 years old in 2025.

What condition is Middle Fork Road over M.Fk.Weiser River 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 August 2023.

How much traffic does Middle Fork Road over M.Fk.Weiser River carry?

About 70 vehicles per day (2023 count), of which roughly 40% are trucks.

How long is Middle Fork Road over M.Fk.Weiser River?

The structure is 36 ft (11 m) long with a longest span of 35 ft (10.7 m) and a deck 27 ft wide.

Who owns Middle Fork Road over M.Fk.Weiser River?

It is owned by the County Highway Agency.