US Bridges

Diamond Valley RD over West Fork Carson River

Fair

Alpine County, California · South of SH 88 · Structure no. 31C0008

Built
1987
38 years old
Condition
Fair
inspected September 2023
Type
Slab
Prestressed Concrete
Length
46 ft
1 main span
Daily traffic
1,000
1988 count
Owner
County
County Highway Agency

About this bridge

Diamond Valley RD over West Fork Carson River is a prestressed concrete slab carrying Diamond Valley RD over West Fork Carson River in Alpine County, California. It was built in 1987, so it is 38 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 1,000 vehicles a day, roughly 3% of them trucks, projected to reach 1,417 by 2041. The structure is 46 ft (14 m) long and 28 ft wide. If it were closed, the detour would be 9.9 mi (16 km).

Location

Open in Google Maps
CarriesDiamond Valley RD
CrossesWest Fork Carson River
LocationSouth of SH 88
RouteCounty Highway 0
CountyAlpine County
StateCalifornia
Coordinates38.80868, -119.77735
Functional classRural Major Collector

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.
Superstructure7 GoodSome minor problems.
Substructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Channel and channel protection7 GoodSome minor problems.
Last inspectionSeptember 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour within limits of footing or piles
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 rating93.9 US tons
Inventory rating35.7 US tons

Structure

Structure typeSlab
MaterialPrestressed Concrete
DeckConcrete, cast-in-place
Main spans1
Design loadHS 20 + Mod
Structure length46 ft (14 m)
Longest span41 ft (12.5 m)
Deck width28 ft (8.5 m)
Roadway width27 ft (8.3 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic1,000 (1988)
Projected traffic1,417 by 2041
Trucks3%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed9.9 mi (16 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—
NavigationNo navigation control on waterway

Frequently asked questions

When was Diamond Valley RD over West Fork Carson River built?

It was built in 1987, making it 38 years old in 2025.

What condition is Diamond Valley RD over West Fork Carson 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 September 2023.

How much traffic does Diamond Valley RD over West Fork Carson River carry?

About 1,000 vehicles per day (1988 count), of which roughly 3% are trucks.

How long is Diamond Valley RD over West Fork Carson River?

The structure is 46 ft (14 m) long with a longest span of 41 ft (12.5 m) and a deck 28 ft wide.

Who owns Diamond Valley RD over West Fork Carson River?

It is owned by the County Highway Agency.