US Bridges

State Route 299 over Dutch Flat Creek

Fair

Modoc County, California · 02-MOD-299-2.45 · Structure no. 03 0056

Built
1936
89 years old, rebuilt 1956
Condition
Fair
inspected August 2023
Type
Culvert
Concrete Continuous
Length
38 ft
2 main spans
Daily traffic
1,110
2015 count
Owner
State
State Highway Agency

About this bridge

State Route 299 over Dutch Flat Creek is a concrete continuous culvert carrying State Route 299 over Dutch Flat Creek in Modoc County, California. It was built in 1936 and reconstructed in 1956, so it is 89 years old, older 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 5 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 1,110 vehicles a day, roughly 11% of them trucks, projected to reach 1,300 by 2040. The structure is 38 ft (11.5 m) long and 40 ft wide. If it were closed, the detour would be 5.6 mi (9 km).

Location

Open in Google Maps
CarriesState Route 299
CrossesDutch Flat Creek
Location02-MOD-299-2.45
RouteState Highway 299
CountyModoc County
StateCalifornia
Coordinates41.21561, -120.93057
Functional classRural Minor Arterial

Condition and inspection

Fair

The lowest-rated primary component is rated 5 or 6. Minor deterioration is present but the structure is sound.

ComponentRatingMeaning
Channel and channel protection7 GoodSome minor problems.
Culvert5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Last inspectionAugust 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation5: Somewhat better than minimum adequacy to tolerate being left in place as is
Deck geometry6: Equal to present minimum criteria
Waterway adequacy7: Better than present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating44.6 US tons
Inventory rating26.8 US tons

Structure

Structure typeCulvert
MaterialConcrete Continuous
DeckNot applicable
Main spans2 (+2 approach)
Design loadUnknown
Structure length38 ft (11.5 m)
Longest span6 ft (1.7 m)
Deck width40 ft (12.3 m)
Roadway width35 ft (10.7 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic1,110 (2015)
Projected traffic1,300 by 2040
Trucks11%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway and pedestrian
CrossesWaterway
Detour if closed5.6 mi (9 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—
NavigationNot applicable (no waterway)

Frequently asked questions

When was State Route 299 over Dutch Flat Creek built?

It was built in 1936, making it 89 years old in 2025. It was reconstructed in 1956.

What condition is State Route 299 over Dutch Flat Creek 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 August 2023.

How much traffic does State Route 299 over Dutch Flat Creek carry?

About 1,110 vehicles per day (2015 count), of which roughly 11% are trucks.

How long is State Route 299 over Dutch Flat Creek?

The structure is 38 ft (11.5 m) long with a longest span of 6 ft (1.7 m) and a deck 40 ft wide.

Who owns State Route 299 over Dutch Flat Creek?

It is owned by the State Highway Agency.