US Bridges

CO RD #99W over Wilson Creek

Good

Glenn County, California · 0.4 MI N CR #45 · Structure no. 11C0191

Built
1927
98 years old, rebuilt 1954
Condition
Good
inspected February 2025
Type
Tee Beam
Concrete
Length
59 ft
3 main spans
Daily traffic
2,678
2009 count
Owner
County
County Highway Agency

About this bridge

CO RD #99W over Wilson Creek is a concrete tee beam carrying CO RD #99W over Wilson Creek in Glenn County, California. It was built in 1927 and reconstructed in 1954, so it is 98 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 2,678 vehicles a day, roughly 20% of them trucks, projected to reach 3,077 by 2047. The structure is 59 ft (18 m) long and 41 ft wide. If it were closed, the detour would be 6.2 mi (10 km).

CarriesCO RD #99W
CrossesWilson Creek
Location0.4 MI N CR #45
RouteCounty Highway 0
Coordinates39.55866, -122.19357
Functional classRural Major Collector

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 protection6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionFebruary 2025
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourScour critical; foundations unstable for calculated scour conditions
Structural evaluation6: Equal to present minimum criteria
Deck geometry6: Equal to present minimum criteria
Waterway adequacy6: Equal to present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating37.1 US tons
Inventory rating28.5 US tons

Structure

Structure typeTee Beam
MaterialConcrete
DeckConcrete, cast-in-place
Main spans3
Design loadH 15
Structure length59 ft (18 m)
Longest span30 ft (9.1 m)
Deck width41 ft (12.4 m)
Roadway width40 ft (12.2 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic2,678 (2009)
Projected traffic3,077 by 2047
Trucks20%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed6.2 mi (10 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 proposedNone recorded
Estimated improvement cost—
NavigationNo navigation control on waterway

Frequently asked questions

When was CO RD #99W over Wilson Creek built?

It was built in 1927, making it 98 years old in 2025. It was reconstructed in 1954.

What condition is CO RD #99W over Wilson Creek 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 February 2025.

How much traffic does CO RD #99W over Wilson Creek carry?

About 2,678 vehicles per day (2009 count), of which roughly 20% are trucks.

How long is CO RD #99W over Wilson Creek?

The structure is 59 ft (18 m) long with a longest span of 30 ft (9.1 m) and a deck 41 ft wide.

Who owns CO RD #99W over Wilson Creek?

It is owned by the County Highway Agency.