US Bridges

State Route 299 over Trinity River

Fair

Trinity County, California · 02-TRI-299-R3.16 · Structure no. 05 0081

Built
1990
35 years old
Condition
Fair
inspected January 2025
Type
Box Beam or Girders - Multiple
Prestressed Concrete Continuous
Length
650 ft
3 main spans
Daily traffic
3,800
2009 count
Owner
State
State Highway Agency

About this bridge

State Route 299 over Trinity River is a prestressed concrete continuous box beam or girders - multiple carrying State Route 299 over Trinity River in Trinity County, California. It was built in 1990, so it is 35 years old, younger than the California average of 54.8 years.

The most recent inspection reported to the Federal Highway Administration rates it in fair condition with a lowest component rating of 5 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 3,800 vehicles a day, projected to reach 4,459 by 2045. The structure is 650 ft (198.1 m) long and 39 ft wide.

Location

Open in Google Maps
CarriesState Route 299
CrossesTrinity River
Location02-TRI-299-R3.16
RouteState Highway 299
CountyTrinity County
StateCalifornia
Coordinates40.88447, -123.55624
Functional classRural Principal Arterial - Other

Condition and inspection

Fair

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

ComponentRatingMeaning
Deck7 GoodSome minor problems.
Superstructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Substructure7 GoodSome minor problems.
Channel and channel protection9 ExcellentNo problems noted.
Last inspectionJanuary 2025
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation5: Somewhat better than minimum adequacy to tolerate being left in place as is
Deck geometry5: Somewhat better than minimum adequacy to tolerate being left in place as is
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating59.6 US tons
Inventory rating35.7 US tons

Structure

Structure typeBox Beam or Girders - Multiple
MaterialPrestressed Concrete Continuous
DeckConcrete, cast-in-place
Main spans3
Design loadHS 20 + Mod
Structure length650 ft (198.1 m)
Longest span260 ft (79.2 m)
Deck width39 ft (12 m)
Roadway width36 ft (11 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic3,800 (2009)
Projected traffic4,459 by 2045
Trucks0%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed—
TollOn a free road
National Highway SystemYes
Strategic Highway NetworkInterstate STRAHNET route

Ownership and planned work

OwnerState Highway Agency
Maintained byState Highway Agency
Historic statusNot eligible for the National Register of Historic Places
Work proposedNone recorded
Estimated improvement cost—
NavigationNo navigation control on waterway

Frequently asked questions

When was State Route 299 over Trinity River built?

It was built in 1990, making it 35 years old in 2025.

What condition is State Route 299 over Trinity River 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 January 2025.

How much traffic does State Route 299 over Trinity River carry?

About 3,800 vehicles per day (2009 count).

How long is State Route 299 over Trinity River?

The structure is 650 ft (198.1 m) long with a longest span of 260 ft (79.2 m) and a deck 39 ft wide.

Who owns State Route 299 over Trinity River?

It is owned by the State Highway Agency.