US Bridges

State Route 29 over Saint Helena Creek

Good

Lake County, California · 01-LAK-029-0.17 · Structure no. 14 0052

Built
1947
78 years old, rebuilt 1993
Condition
Good
inspected October 2024
Type
Slab
Concrete Continuous
Length
173 ft
5 main spans
Daily traffic
7,000
2010 count
Owner
State
State Highway Agency

About this bridge

State Route 29 over Saint Helena Creek is a concrete continuous slab carrying State Route 29 over Saint Helena Creek in Lake County, California. It was built in 1947 and reconstructed in 1993, so it is 78 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 7,000 vehicles a day, roughly 5% of them trucks, projected to reach 9,945 by 2042. The structure is 173 ft (52.7 m) long and 35 ft wide. If it were closed, the detour would be 18 mi (29 km).

CarriesState Route 29
CrossesSaint Helena Creek
Location01-LAK-029-0.17
RouteState Highway 29
Coordinates38.68099, -122.59111
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 protection7 GoodSome minor problems.
Last inspectionOctober 2024
Inspection intervalevery 48 months
Operating statusOpen, no restriction
ScourFoundations stable; scour within limits of footing or piles
Structural evaluation7: Better than present minimum criteria
Deck geometry4: 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 rating72.1 US tons
Inventory rating43.2 US tons

Structure

Structure typeSlab
MaterialConcrete Continuous
DeckConcrete, cast-in-place
Main spans5
Design loadHS 20
Structure length173 ft (52.7 m)
Longest span38 ft (11.6 m)
Deck width35 ft (10.7 m)
Roadway width32 ft (9.8 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic7,000 (2010)
Projected traffic9,945 by 2042
Trucks5%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed18 mi (29 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 29 over Saint Helena Creek built?

It was built in 1947, making it 78 years old in 2025. It was reconstructed in 1993.

What condition is State Route 29 over Saint Helena 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 October 2024.

How much traffic does State Route 29 over Saint Helena Creek carry?

About 7,000 vehicles per day (2010 count), of which roughly 5% are trucks.

How long is State Route 29 over Saint Helena Creek?

The structure is 173 ft (52.7 m) long with a longest span of 38 ft (11.6 m) and a deck 35 ft wide.

Who owns State Route 29 over Saint Helena Creek?

It is owned by the State Highway Agency.