US Bridges

County Road 33 over Left Hand Creek

Fair

Boulder County, Colorado · 0.3 M N of Oxford RD (26) · Structure no. BC-33-1.2-LT

Built
1980
45 years old
Condition
Fair
inspected February 2025
Type
Culvert
Concrete
Length
43 ft
3 main spans
Daily traffic
4,344
2023 count
Owner
County
County Highway Agency

About this bridge

County Road 33 over Left Hand Creek is a concrete culvert carrying County Road 33 over Left Hand Creek in Boulder 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 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 4,344 vehicles a day, roughly 9% of them trucks, projected to reach 5,212 by 2042. The structure is 43 ft (13.2 m) long and 38 ft wide. If it were closed, the detour would be 1.9 mi (3 km).

Location

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CarriesCounty Road 33
CrossesLeft Hand Creek
Location0.3 M N of Oxford RD (26)
RouteCounty Highway 0
CountyBoulder County
StateColorado
Coordinates40.11657, -105.18317
Functional classRural Minor Arterial

Condition and inspection

Fair

The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound.

ComponentRatingMeaning
Channel and channel protection7 GoodSome minor problems.
Culvert6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionFebruary 2025
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 adequacy6: Equal to present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating40 US tons
Inventory rating36 US tons

Structure

Structure typeCulvert
MaterialConcrete
DeckConcrete, cast-in-place
Main spans3
Design loadHS 20
Structure length43 ft (13.2 m)
Longest span16 ft (4.8 m)
Deck width38 ft (11.6 m)
Roadway width35 ft (10.7 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic4,344 (2023)
Projected traffic5,212 by 2042
Trucks9%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed1.9 mi (3 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—
NavigationNot applicable (no waterway)

Frequently asked questions

When was County Road 33 over Left Hand Creek built?

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

What condition is County Road 33 over Left Hand 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 February 2025.

How much traffic does County Road 33 over Left Hand Creek carry?

About 4,344 vehicles per day (2023 count), of which roughly 9% are trucks.

How long is County Road 33 over Left Hand Creek?

The structure is 43 ft (13.2 m) long with a longest span of 16 ft (4.8 m) and a deck 38 ft wide.

Who owns County Road 33 over Left Hand Creek?

It is owned by the County Highway Agency.