US Bridges

Boulder Lake over Coffee Creek

Good

Trinity County, California · No Data Entered · Structure no. 051456000001087

Built
1965
60 years old
Condition
Good
inspected May 2023
Type
Box Beam or Girders - Single or Spread
Concrete
Length
82 ft
1 main span
Daily traffic
50
Owner
Federal
U.S. Forest Service

About this bridge

Boulder Lake over Coffee Creek is a concrete box beam or girders - single or spread carrying Boulder Lake over Coffee Creek in Trinity County, California. It was built in 1965, so it is 60 years old, older than the California average of 54.8 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 50 vehicles a day, projected to reach 75 by 2045. The structure is 82 ft (25.1 m) long and 16 ft wide.

CarriesBoulder Lake
CrossesCoffee Creek
LocationNo Data Entered
RouteFederal Lands Road 37N19
Coordinates41.1, -122.78
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
Deck7 GoodSome minor problems.
Superstructure7 GoodSome minor problems.
Substructure7 GoodSome minor problems.
Channel and channel protection8 Very GoodNo problems noted.
Last inspectionMay 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour within limits of footing or piles
Structural evaluation*: *
Deck geometry6: Equal to present minimum criteria
Waterway adequacy9: Superior to present desirable criteria
Approach roadway alignment7: Better than present minimum criteria
Operating rating—
Inventory rating—

Structure

MaterialConcrete
DeckConcrete, cast-in-place
Main spans1
Design loadHS 20
Structure length82 ft (25.1 m)
Longest span81 ft (24.7 m)
Deck width16 ft (5 m)
Roadway width14 ft (4.3 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic50 (—)
Projected traffic75 by 2045
Trucks—
Lanes on structure1
Traffic directionOne-lane bridge for two-way traffic
CarriesHighway
CrossesWaterway
Detour if closed—
TollOn a free road
National Highway SystemNo

Ownership and planned work

OwnerU.S. Forest Service
Maintained byU.S. Forest Service
Historic statusHistorical significance not determinable at this time
Work proposedNone recorded
Estimated improvement cost—
NavigationNo navigation control on waterway

Frequently asked questions

When was Boulder Lake over Coffee Creek built?

It was built in 1965, making it 60 years old in 2025.

What condition is Boulder Lake over Coffee 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 May 2023.

How much traffic does Boulder Lake over Coffee Creek carry?

About 50 vehicles per day (latest count).

How long is Boulder Lake over Coffee Creek?

The structure is 82 ft (25.1 m) long with a longest span of 81 ft (24.7 m) and a deck 16 ft wide.

Who owns Boulder Lake over Coffee Creek?

It is owned by the U.S. Forest Service.