US Bridges

County Road 129 over Elk River

FairPosted for load

Routt County, Colorado · 18.1 MI N of US HWY 40 · Structure no. 107012918.10908

Built
1981
44 years old
Condition
Fair
inspected October 2024
Type
Girder and Floorbeam System
Steel Continuous
Length
79 ft
2 main spans
Daily traffic
2,058
2023 count
Owner
County
County Highway Agency

About this bridge

County Road 129 over Elk River is a steel continuous girder and floorbeam system carrying County Road 129 over Elk River in Routt County, Colorado. It was built in 1981, so it is 44 years old, older than the Colorado average of 42.2 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. Its operating status is: posted for load restriction.

It carries about 2,058 vehicles a day, roughly 31% of them trucks, projected to reach 2,449 by 2042. The structure is 79 ft (24.1 m) long and 26 ft wide. If it were closed, the detour would be 3.7 mi (6 km).

Location

Open in Google Maps
CarriesCounty Road 129
CrossesElk River
Location18.1 MI N of US HWY 40
RouteCounty Highway 0
CountyRoutt County
StateColorado
Coordinates40.71744, -106.91532
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
Deck7 GoodSome minor problems.
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 inspectionOctober 2024
Inspection intervalevery 24 months
Operating statusPosted for load restriction
ScourFoundations stable; scour within limits of footing or piles
Structural evaluation3: Basically intolerable, requiring high priority of corrective action
Deck geometry2: Basically intolerable, requiring high priority of replacement
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating19.2 US tons
Inventory rating11.5 US tons

Structure

Structure typeGirder and Floorbeam System
MaterialSteel Continuous
DeckCorrugated steel
Main spans2
Design loadHS 20
Structure length79 ft (24.1 m)
Longest span35 ft (10.8 m)
Deck width26 ft (8 m)
Roadway width24 ft (7.3 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic2,058 (2023)
Projected traffic2,449 by 2042
Trucks31%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed3.7 mi (6 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 County Road 129 over Elk River built?

It was built in 1981, making it 44 years old in 2025.

What condition is County Road 129 over Elk 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 October 2024.

How much traffic does County Road 129 over Elk River carry?

About 2,058 vehicles per day (2023 count), of which roughly 31% are trucks.

How long is County Road 129 over Elk River?

The structure is 79 ft (24.1 m) long with a longest span of 35 ft (10.8 m) and a deck 26 ft wide.

Who owns County Road 129 over Elk River?

It is owned by the County Highway Agency.