US Bridges

Paved Road over Twin Lakes Dam

Good

Mono County, California · Lake Mary Road · Structure no. 050453000001010

Built
2000
25 years old
Condition
Good
inspected September 2024
Type
Slab
Prestressed Concrete
Length
72 ft
1 main span
Daily traffic
50
Owner
Federal
U.S. Forest Service

About this bridge

Paved Road over Twin Lakes Dam is a prestressed concrete slab carrying Paved Road over Twin Lakes Dam in Mono County, California. It was built in 2000, so it is 25 years old, younger 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 72 ft (21.9 m) long and 36 ft wide. If it were closed, the detour would be 98.2 mi (158 km).

CarriesPaved Road
CrossesTwin Lakes Dam
LocationLake Mary Road
RouteFederal Lands Road 3S10
Coordinates37.62378, -119.00597
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 inspectionSeptember 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation7: Better than present minimum criteria
Deck geometry8: Equal to present desirable criteria
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment7: Better than present minimum criteria
Operating rating46.7 US tons
Inventory rating36 US tons

Structure

Structure typeSlab
MaterialPrestressed Concrete
DeckOther
Main spans1
Design loadHS 20
Structure length72 ft (21.9 m)
Longest span71 ft (21.6 m)
Deck width36 ft (11 m)
Roadway width32 ft (9.8 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic50 (—)
Projected traffic75 by 2045
Trucks—
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway and pedestrian
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—
NavigationNo navigation control on waterway

Frequently asked questions

When was Paved Road over Twin Lakes Dam built?

It was built in 2000, making it 25 years old in 2025.

What condition is Paved Road over Twin Lakes Dam 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 September 2024.

How much traffic does Paved Road over Twin Lakes Dam carry?

About 50 vehicles per day (latest count).

How long is Paved Road over Twin Lakes Dam?

The structure is 72 ft (21.9 m) long with a longest span of 71 ft (21.6 m) and a deck 36 ft wide.

Who owns Paved Road over Twin Lakes Dam?

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