US Bridges

State Route 49 over Downie River

Good

Sierra County, California · 03-SIE-049-16.75 · Structure no. 13 0005

Built
1938
87 years old, rebuilt 1992
Condition
Good
inspected July 2024
Type
Truss - Thru
Steel
Length
142 ft
1 main span
Daily traffic
1,200
2015 count
Owner
State
State Highway Agency

About this bridge

State Route 49 over Downie River is a steel truss - thru carrying State Route 49 over Downie River in Sierra County, California. It was built in 1938 and reconstructed in 1992, so it is 87 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 1,200 vehicles a day, projected to reach 1,734 by 2046. The structure is 142 ft (43.3 m) long and 14 ft wide. If it were closed, the detour would be 123.7 mi (199 km).

CarriesState Route 49
CrossesDownie River
Location03-SIE-049-16.75
RouteState Highway 49
Coordinates39.56004, -120.82797
Functional classRural Minor Arterial

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.
Substructure8 Very GoodNo problems noted.
Channel and channel protection8 Very GoodNo problems noted.
Last inspectionJuly 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourUnknown foundation; not evaluated for scour
Structural evaluation5: Somewhat better than minimum adequacy to tolerate being left in place as is
Deck geometry2: Basically intolerable, requiring high priority of replacement
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating35.4 US tons
Inventory rating21.1 US tons

Structure

Structure typeTruss - Thru
MaterialSteel
DeckCorrugated steel
Main spans1 (+1 approach)
Design loadH 15
Structure length142 ft (43.3 m)
Longest span120 ft (36.6 m)
Deck width14 ft (4.4 m)
Roadway width12 ft (3.8 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic1,200 (2015)
Projected traffic1,734 by 2046
Trucks0%
Lanes on structure1
Traffic directionOne-lane bridge for two-way traffic
CarriesHighway and pedestrian
CrossesWaterway
Detour if closed123.7 mi (199 km)
TollOn a free road
National Highway SystemNo

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 49 over Downie River built?

It was built in 1938, making it 87 years old in 2025. It was reconstructed in 1992.

What condition is State Route 49 over Downie River 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 July 2024.

How much traffic does State Route 49 over Downie River carry?

About 1,200 vehicles per day (2015 count).

How long is State Route 49 over Downie River?

The structure is 142 ft (43.3 m) long with a longest span of 120 ft (36.6 m) and a deck 14 ft wide.

Who owns State Route 49 over Downie River?

It is owned by the State Highway Agency.