US Bridges

County Road 306 over Branch Stony Creek

Poor

Glenn County, California · 9.98 MI N CO Line · Structure no. 11C0202

Built
1930
95 years old, rebuilt 1970
Condition
Poor
inspected August 2023
Type
Culvert
Concrete Continuous
Length
22 ft
2 main spans
Daily traffic
235
2009 count
Owner
County
County Highway Agency

About this bridge

County Road 306 over Branch Stony Creek is a concrete continuous culvert carrying County Road 306 over Branch Stony Creek in Glenn County, California. It was built in 1930 and reconstructed in 1970, so it is 95 years old, older than the California average of 54.8 years.

The most recent inspection reported to the Federal Highway Administration rates it in poor condition with a lowest component rating of 4 out of 9. The lowest-rated primary component is rated 4 or below, indicating advanced deterioration. Poor does not mean unsafe; such bridges are inspected more often and may carry load restrictions.

It carries about 235 vehicles a day, roughly 15% of them trucks, projected to reach 220 by 2043. The structure is 22 ft (6.7 m) long. If it were closed, the detour would be 1.2 mi (2 km).

Location

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CarriesCounty Road 306
CrossesBranch Stony Creek
Location9.98 MI N CO Line
RouteCounty Highway 0
CountyGlenn County
StateCalifornia
Coordinates39.50339, -122.52579
Functional classRural Major Collector

Condition and inspection

Poor

The lowest-rated primary component is rated 4 or below, indicating advanced deterioration. Poor does not mean unsafe; such bridges are inspected more often and may carry load restrictions.

ComponentRatingMeaning
Channel and channel protection7 GoodSome minor problems.
Culvert4 PoorAdvanced section loss, deterioration, spalling or scour.
Last inspectionAugust 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation4: Meets minimum tolerable limits to be left in place as is
Waterway adequacy9: Superior to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating30 US tons
Inventory rating17.9 US tons

Structure

Structure typeCulvert
MaterialConcrete Continuous
DeckNot applicable
Main spans2
Design loadUnknown
Structure length22 ft (6.7 m)
Longest span10 ft (3 m)
Deck width0 ft (0 m)
Roadway width0 ft (0 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic235 (2009)
Projected traffic220 by 2043
Trucks15%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed1.2 mi (2 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 proposedReplacement because of substandard load-carrying capacity or roadway geometry
Estimated improvement cost$784,000 (2020 estimate)
NavigationNo navigation control on waterway

Frequently asked questions

When was County Road 306 over Branch Stony Creek built?

It was built in 1930, making it 95 years old in 2025. It was reconstructed in 1970.

What condition is County Road 306 over Branch Stony Creek in?

The National Bridge Inventory rates it in poor condition. The lowest-rated primary component is rated 4 or below, indicating advanced deterioration. Poor does not mean unsafe; such bridges are inspected more often and may carry load restrictions. The last reported inspection was in August 2023.

How much traffic does County Road 306 over Branch Stony Creek carry?

About 235 vehicles per day (2009 count), of which roughly 15% are trucks.

How long is County Road 306 over Branch Stony Creek?

The structure is 22 ft (6.7 m) long with a longest span of 10 ft (3 m).

Who owns County Road 306 over Branch Stony Creek?

It is owned by the County Highway Agency.