US Bridges

Colorado Avenue over Skunk Creek

Fair

Boulder County, Colorado · At 38th Street · Structure no. BOLD-37-COLOAVE

Built
1979
46 years old
Condition
Fair
inspected February 2025
Type
Culvert
Concrete
Length
31 ft
2 main spans
Daily traffic
7,343
2023 count
Owner
City
City or Municipal Highway Agency

About this bridge

Colorado Avenue over Skunk Creek is a concrete culvert carrying Colorado Avenue over Skunk Creek in Boulder County, Colorado. It was built in 1979, so it is 46 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 7,343 vehicles a day, roughly 6% of them trucks, projected to reach 8,811 by 2043. The structure is 31 ft (9.4 m) long and 107 ft wide. If it were closed, the detour would be 1.2 mi (2 km).

CarriesColorado Avenue
CrossesSkunk Creek
LocationAt 38th Street
RouteCity Street 0
Coordinates40.00726, -105.24507
Functional classUrban 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 geometry9: Superior to present desirable criteria
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating40 US tons
Inventory rating36 US tons

Structure

Structure typeCulvert
MaterialConcrete
DeckNot applicable
Main spans2
Design loadUnknown
Structure length31 ft (9.4 m)
Longest span15 ft (4.5 m)
Deck width107 ft (32.6 m)
Roadway width105 ft (31.9 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic7,343 (2023)
Projected traffic8,811 by 2043
Trucks6%
Lanes on structure4
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—
NavigationNot applicable (no waterway)

Frequently asked questions

When was Colorado Avenue over Skunk Creek built?

It was built in 1979, making it 46 years old in 2025.

What condition is Colorado Avenue over Skunk 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 Colorado Avenue over Skunk Creek carry?

About 7,343 vehicles per day (2023 count), of which roughly 6% are trucks.

How long is Colorado Avenue over Skunk Creek?

The structure is 31 ft (9.4 m) long with a longest span of 15 ft (4.5 m) and a deck 107 ft wide.

Who owns Colorado Avenue over Skunk Creek?

It is owned by the City or Municipal Highway Agency.