US Bridges

County Road 81 over James Creek

Good

Boulder County, Colorado · 25 Ft S of Lefthand Cyn · Structure no. BC-81-5.4-JA

Built
2019
6 years old
Condition
Good
inspected February 2025
Type
Box Beam or Girders - Multiple
Prestressed Concrete
Length
48 ft
1 main span
Daily traffic
777
2023 count
Owner
County
County Highway Agency

About this bridge

County Road 81 over James Creek is a prestressed concrete box beam or girders - multiple carrying County Road 81 over James Creek in Boulder County, Colorado. It was built in 2019, so it is 6 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 777 vehicles a day, roughly 8% of them trucks, projected to reach 932 by 2042. The structure is 48 ft (14.5 m) long and 30 ft wide. If it were closed, the detour would be 1.2 mi (2 km).

Location

Open in Google Maps
CarriesCounty Road 81
CrossesJames Creek
Location25 Ft S of Lefthand Cyn
RouteCounty Highway 0
CountyBoulder County
StateColorado
Coordinates40.10204, -105.34218
Functional classRural Local

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.
Superstructure7 GoodSome minor problems.
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 within limits of footing or piles
Structural evaluation7: Better than present minimum criteria
Deck geometry6: Equal to present minimum criteria
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment7: Better than present minimum criteria
Operating rating97.1 US tons
Inventory rating75 US tons

Structure

Structure typeBox Beam or Girders - Multiple
MaterialPrestressed Concrete
DeckOther
Main spans1
Design loadHL 93
Structure length48 ft (14.5 m)
Longest span43 ft (13 m)
Deck width30 ft (9.1 m)
Roadway width30 ft (9.1 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic777 (2023)
Projected traffic932 by 2042
Trucks8%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed1.2 mi (2 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 81 over James Creek built?

It was built in 2019, making it 6 years old in 2025.

What condition is County Road 81 over James Creek 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 County Road 81 over James Creek carry?

About 777 vehicles per day (2023 count), of which roughly 8% are trucks.

How long is County Road 81 over James Creek?

The structure is 48 ft (14.5 m) long with a longest span of 43 ft (13 m) and a deck 30 ft wide.

Who owns County Road 81 over James Creek?

It is owned by the County Highway Agency.