US Bridges

State Route 299 over Ash Creek

Good

Modoc County, California · 02-MOD-299-1.02 · Structure no. 03 0064

Built
2020
5 years old
Condition
Good
inspected April 2023
Type
Slab
Prestressed Concrete
Length
150 ft
3 main spans
Daily traffic
1,600
2015 count
Owner
State
State Highway Agency

About this bridge

State Route 299 over Ash Creek is a prestressed concrete slab carrying State Route 299 over Ash Creek in Modoc County, California. It was built in 2020, so it is 5 years old, younger 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 1,600 vehicles a day, roughly 21% of them trucks, projected to reach 1,800 by 2040. The structure is 150 ft (45.7 m) long and 44 ft wide. If it were closed, the detour would be 1.2 mi (2 km).

Location

Open in Google Maps
CarriesState Route 299
CrossesAsh Creek
Location02-MOD-299-1.02
RouteState Highway 299
CountyModoc County
StateCalifornia
Coordinates41.19754, -120.94409
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.
Substructure7 GoodSome minor problems.
Channel and channel protection6 SatisfactoryStructural elements show some minor deterioration.
Last inspectionApril 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour within limits of footing or piles
Structural evaluation7: Better than present minimum criteria
Deck geometry7: Better than present minimum criteria
Waterway adequacy7: Better than present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating46.4 US tons
Inventory rating35.7 US tons

Structure

Structure typeSlab
MaterialPrestressed Concrete
DeckConcrete, cast-in-place
Main spans3
Design loadHL 93
Structure length150 ft (45.7 m)
Longest span50 ft (15.2 m)
Deck width44 ft (13.4 m)
Roadway width40 ft (12.2 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic1,600 (2015)
Projected traffic1,800 by 2040
Trucks21%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway and pedestrian
CrossesWaterway
Detour if closed1.2 mi (2 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 299 over Ash Creek built?

It was built in 2020, making it 5 years old in 2025.

What condition is State Route 299 over Ash 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 April 2023.

How much traffic does State Route 299 over Ash Creek carry?

About 1,600 vehicles per day (2015 count), of which roughly 21% are trucks.

How long is State Route 299 over Ash Creek?

The structure is 150 ft (45.7 m) long with a longest span of 50 ft (15.2 m) and a deck 44 ft wide.

Who owns State Route 299 over Ash Creek?

It is owned by the State Highway Agency.