US Bridges

Road 30N06 over Susan River

Fair

Lassen County, California · No Data Entered · Structure no. 050658000001004

Built
1976
49 years old, rebuilt 1997
Condition
Fair
inspected May 2024
Type
Truss - Deck
Steel
Length
50 ft
1 main span
Daily traffic
20
Owner
Federal
U.S. Forest Service

About this bridge

Road 30N06 over Susan River is a steel truss - deck carrying Road 30N06 over Susan River in Lassen County, California. It was built in 1976 and reconstructed in 1997, so it is 49 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 6 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 20 vehicles a day, projected to reach 30 by 2045. The structure is 50 ft (15.2 m) long and 15 ft wide.

Location

Open in Google Maps
CarriesRoad 30N06
CrossesSusan River
LocationNo Data Entered
RouteFederal Lands Road 30N06
CountyLassen County
StateCalifornia
Coordinates40.43272, -120.9295
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
Deck7 GoodSome minor problems.
Superstructure6 SatisfactoryStructural elements show some minor deterioration.
Substructure7 GoodSome minor problems.
Channel and channel protection7 GoodSome minor problems.
Last inspectionMay 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour within limits of footing or piles
Structural evaluation*: *
Deck geometry6: Equal to present minimum criteria
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment6: Equal to present minimum criteria
Operating rating—
Inventory rating—

Structure

Structure typeTruss - Deck
MaterialSteel
DeckWood or timber
Main spans1
Design loadH 20
Structure length50 ft (15.2 m)
Longest span50 ft (15.2 m)
Deck width15 ft (4.6 m)
Roadway width14 ft (4.3 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic20 (—)
Projected traffic30 by 2045
Trucks—
Lanes on structure1
Traffic directionOne-lane bridge for two-way traffic
CarriesHighway
CrossesWaterway
Detour if closed—
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$30,000
NavigationNo navigation control on waterway

Frequently asked questions

When was Road 30N06 over Susan River built?

It was built in 1976, making it 49 years old in 2025. It was reconstructed in 1997.

What condition is Road 30N06 over Susan 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 May 2024.

How much traffic does Road 30N06 over Susan River carry?

About 20 vehicles per day (latest count).

How long is Road 30N06 over Susan River?

The structure is 50 ft (15.2 m) long with a longest span of 50 ft (15.2 m) and a deck 15 ft wide.

Who owns Road 30N06 over Susan River?

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