US Bridges

County Road 15 over Boxelder Creek

Fair

Larimer County, Colorado · 0.8 MI N of CO RD 78 · Structure no. LR15-0.8-78

Built
1980
45 years old
Condition
Fair
inspected May 2023
Type
Tee Beam
Prestressed Concrete
Length
64 ft
1 main span
Daily traffic
365
2023 count
Owner
County
County Highway Agency

About this bridge

County Road 15 over Boxelder Creek is a prestressed concrete tee beam carrying County Road 15 over Boxelder Creek in Larimer County, Colorado. It was built in 1980, so it is 45 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.

It carries about 365 vehicles a day, roughly 29% of them trucks, projected to reach 457 by 2042. The structure is 64 ft (19.5 m) long and 43 ft wide. If it were closed, the detour would be 3.7 mi (6 km).

Location

Open in Google Maps
CarriesCounty Road 15
CrossesBoxelder Creek
Location0.8 MI N of CO RD 78
RouteCounty Highway 0
CountyLarimer County
StateColorado
Coordinates40.8235, -105.07614
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.
Superstructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Channel and channel protection7 GoodSome minor problems.
Last inspectionMay 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour within limits of footing or piles
Structural evaluation4: Meets minimum tolerable limits to be left in place as is
Deck geometry9: Superior to present desirable criteria
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating44.8 US tons
Inventory rating14.3 US tons

Structure

Structure typeTee Beam
MaterialPrestressed Concrete
DeckConcrete, cast-in-place
Main spans1
Design loadUnknown
Structure length64 ft (19.5 m)
Longest span59 ft (18.1 m)
Deck width43 ft (13 m)
Roadway width40 ft (12.2 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic365 (2023)
Projected traffic457 by 2042
Trucks29%
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 15 over Boxelder Creek built?

It was built in 1980, making it 45 years old in 2025.

What condition is County Road 15 over Boxelder 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 May 2023.

How much traffic does County Road 15 over Boxelder Creek carry?

About 365 vehicles per day (2023 count), of which roughly 29% are trucks.

How long is County Road 15 over Boxelder Creek?

The structure is 64 ft (19.5 m) long with a longest span of 59 ft (18.1 m) and a deck 43 ft wide.

Who owns County Road 15 over Boxelder Creek?

It is owned by the County Highway Agency.