US Bridges

Crags Drive over Big Thompson River

Good

Larimer County, Colorado · 50 Feet North of E Rivers · Structure no. EP-CRAGS-THOM

Built
1985
40 years old
Condition
Good
inspected September 2024
Type
Tee Beam
Prestressed Concrete
Length
64 ft
1 main span
Daily traffic
3,972
2023 count
Owner
City
City or Municipal Highway Agency

About this bridge

Crags Drive over Big Thompson River is a prestressed concrete tee beam carrying Crags Drive over Big Thompson River in Larimer County, Colorado. It was built in 1985, so it is 40 years old, younger than the Colorado average of 42.2 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 3,972 vehicles a day, roughly 11% of them trucks, projected to reach 4,965 by 2043. The structure is 64 ft (19.5 m) long and 39 ft wide. If it were closed, the detour would be 1.2 mi (2 km).

CarriesCrags Drive
CrossesBig Thompson River
Location50 Feet North of E Rivers
RouteCity Street 0
Coordinates40.37158, -105.52364
Functional classUrban 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.
Substructure7 GoodSome minor problems.
Channel and channel protection8 Very GoodNo problems noted.
Last inspectionSeptember 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation6: Equal to present minimum criteria
Deck geometry4: Meets minimum tolerable limits to be left in place as is
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating66.8 US tons
Inventory rating28.8 US tons

Structure

Structure typeTee Beam
MaterialPrestressed Concrete
DeckConcrete, cast-in-place
Main spans1
Design loadHS 20
Structure length64 ft (19.5 m)
Longest span59 ft (18 m)
Deck width39 ft (11.8 m)
Roadway width28 ft (8.6 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic3,972 (2023)
Projected traffic4,965 by 2043
Trucks11%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway and pedestrian
CrossesWaterway
Detour if closed1.2 mi (2 km)
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerCity or Municipal Highway Agency
Maintained byCity or Municipal 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 Crags Drive over Big Thompson River built?

It was built in 1985, making it 40 years old in 2025.

What condition is Crags Drive over Big Thompson 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 Crags Drive over Big Thompson River carry?

About 3,972 vehicles per day (2023 count), of which roughly 11% are trucks.

How long is Crags Drive over Big Thompson River?

The structure is 64 ft (19.5 m) long with a longest span of 59 ft (18 m) and a deck 39 ft wide.

Who owns Crags Drive over Big Thompson River?

It is owned by the City or Municipal Highway Agency.