US Bridges

Sixty-Eighth Ave over South Fork Antelope Crk

Poor

Tehama County, California · At SR 99 · Structure no. 08C0104

Built
1929
96 years old, rebuilt 1996
Condition
Poor
inspected September 2024
Type
Stringer/Multi-beam or Girder
Steel
Length
38 ft
2 main spans
Daily traffic
500
2022 count
Owner
County
County Highway Agency

About this bridge

Sixty-Eighth Ave over South Fork Antelope Crk is a steel stringer/multi-beam or girder carrying Sixty-Eighth Ave over South Fork Antelope Crk in Tehama County, California. It was built in 1929 and reconstructed in 1996, so it is 96 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 500 vehicles a day, roughly 3% of them trucks, projected to reach 544 by 2046. The structure is 38 ft (11.6 m) long and 20 ft wide. If it were closed, the detour would be 5 mi (8 km).

CarriesSixty-Eighth Ave
CrossesSouth Fork Antelope Crk
LocationAt SR 99
RouteCounty Highway 0
Coordinates40.10833, -122.11
Functional classRural Local

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
Deck7 GoodSome minor problems.
Superstructure6 SatisfactoryStructural elements show some minor deterioration.
Substructure4 PoorAdvanced section loss, deterioration, spalling or scour.
Channel and channel protection4 PoorAdvanced section loss, deterioration, spalling or scour.
Last inspectionSeptember 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourScour critical; foundations unstable for calculated scour conditions
Structural evaluation4: Meets minimum tolerable limits to be left in place as is
Deck geometry2: Basically intolerable, requiring high priority of replacement
Waterway adequacy4: Meets minimum tolerable limits to be left in place as is
Approach roadway alignment6: Equal to present minimum criteria
Operating rating63.6 US tons
Inventory rating38.3 US tons

Structure

MaterialSteel
DeckCorrugated steel
Main spans2
Design loadUnknown
Structure length38 ft (11.6 m)
Longest span18 ft (5.5 m)
Deck width20 ft (6.1 m)
Roadway width20 ft (6 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic500 (2022)
Projected traffic544 by 2046
Trucks3%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed5 mi (8 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$274,000 (2023 estimate)
NavigationNo navigation control on waterway

Frequently asked questions

When was Sixty-Eighth Ave over South Fork Antelope Crk built?

It was built in 1929, making it 96 years old in 2025. It was reconstructed in 1996.

What condition is Sixty-Eighth Ave over South Fork Antelope Crk 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 September 2024.

How much traffic does Sixty-Eighth Ave over South Fork Antelope Crk carry?

About 500 vehicles per day (2022 count), of which roughly 3% are trucks.

How long is Sixty-Eighth Ave over South Fork Antelope Crk?

The structure is 38 ft (11.6 m) long with a longest span of 18 ft (5.5 m) and a deck 20 ft wide.

Who owns Sixty-Eighth Ave over South Fork Antelope Crk?

It is owned by the County Highway Agency.