US Bridges

Road over Carbon River

Fair

Pierce County, Washington · .1 MI N of 78 / 7810 Jct. · Structure no. 060507000003032

Built
2001
24 years old
Condition
Fair
inspected August 2024
Type
Stringer/Multi-beam or Girder
Prestressed Concrete
Length
702 ft
6 main spans
Daily traffic
95
Owner
Federal
U.S. Forest Service

About this bridge

Road over Carbon River is a prestressed concrete stringer/multi-beam or girder carrying Road over Carbon River in Pierce County, Washington. It was built in 2001, so it is 24 years old, younger than the Washington average of 49.8 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 95 vehicles a day, projected to reach 142 by 2045. The structure is 702 ft (214 m) long and 17 ft wide. If it were closed, the detour would be 98.2 mi (158 km).

Location

Open in Google Maps
CarriesRoad
CrossesCarbon River
Location.1 MI N of 78 / 7810 Jct.
RouteFederal Lands Road 78100
CountyPierce County
StateWashington
Coordinates46.9958, -121.9192
Functional classRural Local

Condition and inspection

Fair

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

ComponentRatingMeaning
Deck5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Superstructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Channel and channel protection7 GoodSome minor problems.
Last inspectionAugust 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations on dry land well above flood water elevations
Structural evaluation5: Somewhat better than minimum adequacy to tolerate being left in place as is
Deck geometry6: Equal to present minimum criteria
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment6: Equal to present minimum criteria
Operating rating55 US tons
Inventory rating32.1 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialPrestressed Concrete
DeckOther
Main spans6
Design loadHS 25 or greater
Structure length702 ft (214 m)
Longest span116 ft (35.5 m)
Deck width17 ft (5.1 m)
Roadway width14 ft (4.3 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic95 (—)
Projected traffic142 by 2045
Trucks—
Lanes on structure1
Traffic directionOne-lane bridge for two-way traffic
CarriesHighway
CrossesWaterway
Detour if closed98.2 mi (158 km)
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—
NavigationNot applicable (no waterway)

Frequently asked questions

When was Road over Carbon River built?

It was built in 2001, making it 24 years old in 2025.

What condition is Road over Carbon 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 August 2024.

How much traffic does Road over Carbon River carry?

About 95 vehicles per day (latest count).

How long is Road over Carbon River?

The structure is 702 ft (214 m) long with a longest span of 116 ft (35.5 m) and a deck 17 ft wide.

Who owns Road over Carbon River?

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