US Bridges

US 36 Ml over Little Thompson River

Fair

Larimer County, Colorado · 11.1 MI SE of JCT SH 7 · Structure no. C-15-N

Built
1937
88 years old, rebuilt 1992
Condition
Fair
inspected July 2023
Type
Stringer/Multi-beam or Girder
Steel
Length
43 ft
1 main span
Daily traffic
6,500
2020 count
Owner
State
State Highway Agency

About this bridge

US 36 Ml over Little Thompson River is a steel stringer/multi-beam or girder carrying US 36 Ml over Little Thompson River in Larimer County, Colorado. It was built in 1937 and reconstructed in 1992, so it is 88 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 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 6,500 vehicles a day, roughly 2% of them trucks, projected to reach 8,385 by 2040. The structure is 43 ft (13.2 m) long and 43 ft wide. If it were closed, the detour would be 62.1 mi (100 km).

CarriesUS 36 Ml
CrossesLittle Thompson River
Location11.1 MI SE of JCT SH 7
RouteU.S. Route 36B
Coordinates40.28347, -105.36372
Functional classRural Principal Arterial - Other

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 inspectionJuly 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation6: Equal to present minimum criteria
Deck geometry5: Somewhat better than minimum adequacy to tolerate being left in place as is
Waterway adequacy9: Superior to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating66.2 US tons
Inventory rating39.7 US tons

Structure

MaterialSteel
DeckConcrete, cast-in-place
Main spans1
Design loadHS 20 + Mod
Structure length43 ft (13.2 m)
Longest span40 ft (12.2 m)
Deck width43 ft (13.1 m)
Roadway width40 ft (12.2 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic6,500 (2020)
Projected traffic8,385 by 2040
Trucks2%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed62.1 mi (100 km)
TollOn a free road
National Highway SystemYes

Ownership and planned work

OwnerState Highway Agency
Maintained byState 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 US 36 Ml over Little Thompson River built?

It was built in 1937, making it 88 years old in 2025. It was reconstructed in 1992.

What condition is US 36 Ml over Little Thompson 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 July 2023.

How much traffic does US 36 Ml over Little Thompson River carry?

About 6,500 vehicles per day (2020 count), of which roughly 2% are trucks.

How long is US 36 Ml over Little Thompson River?

The structure is 43 ft (13.2 m) long with a longest span of 40 ft (12.2 m) and a deck 43 ft wide.

Who owns US 36 Ml over Little Thompson River?

It is owned by the State Highway Agency.