US Bridges

Niwot Road (cr 34) over Boulder Feeder Canal

Good

Boulder County, Colorado · 100 Ft. E of N. 55th ST · Structure no. BC-34-3.3-ID-A

Built
2010
15 years old
Condition
Good
inspected February 2025
Type
Slab
Prestressed Concrete
Length
37 ft
1 main span
Daily traffic
2,084
2023 count
Owner
County
County Highway Agency

About this bridge

Niwot Road (cr 34) over Boulder Feeder Canal is a prestressed concrete slab carrying Niwot Road (cr 34) over Boulder Feeder Canal in Boulder County, Colorado. It was built in 2010, so it is 15 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 8 out of 9. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

It carries about 2,084 vehicles a day, roughly 11% of them trucks, projected to reach 2,500 by 2043. The structure is 37 ft (11.3 m) long and 50 ft wide. If it were closed, the detour would be 1.9 mi (3 km).

Location

Open in Google Maps
CarriesNiwot Road (cr 34)
CrossesBoulder Feeder Canal
Location100 Ft. E of N. 55th ST
RouteCounty Highway 0
CountyBoulder County
StateColorado
Coordinates40.10164, -105.22532
Functional classRural Minor Collector

Condition and inspection

Good

All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

ComponentRatingMeaning
Deck8 Very GoodNo problems noted.
Superstructure8 Very GoodNo problems noted.
Substructure8 Very GoodNo problems noted.
Channel and channel protection8 Very GoodNo problems noted.
Last inspectionFebruary 2025
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation8: Equal to present desirable criteria
Deck geometry9: Superior to present desirable criteria
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating61.2 US tons
Inventory rating36.6 US tons

Structure

Structure typeSlab
MaterialPrestressed Concrete
DeckConcrete, cast-in-place
Main spans1
Design loadHS 20
Structure length37 ft (11.3 m)
Longest span33 ft (10.1 m)
Deck width50 ft (15.2 m)
Roadway width48 ft (14.6 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic2,084 (2023)
Projected traffic2,500 by 2043
Trucks11%
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 Niwot Road (cr 34) over Boulder Feeder Canal built?

It was built in 2010, making it 15 years old in 2025.

What condition is Niwot Road (cr 34) over Boulder Feeder Canal 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 February 2025.

How much traffic does Niwot Road (cr 34) over Boulder Feeder Canal carry?

About 2,084 vehicles per day (2023 count), of which roughly 11% are trucks.

How long is Niwot Road (cr 34) over Boulder Feeder Canal?

The structure is 37 ft (11.3 m) long with a longest span of 33 ft (10.1 m) and a deck 50 ft wide.

Who owns Niwot Road (cr 34) over Boulder Feeder Canal?

It is owned by the County Highway Agency.