US Bridges

Grayson Road over Laird Slough

Fair

Stanislaus County, California · 3.1 MI N/E State Route 33 · Structure no. 38C0027

Built
1962
63 years old
Condition
Fair
inspected October 2023
Type
Tee Beam
Concrete Continuous
Length
408 ft
3 main spans
Daily traffic
5,299
2019 count
Owner
County
County Highway Agency

About this bridge

Grayson Road over Laird Slough is a concrete continuous tee beam carrying Grayson Road over Laird Slough in Stanislaus County, California. It was built in 1962, so it is 63 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 5,299 vehicles a day, roughly 26% of them trucks, projected to reach 6,883 by 2040. The structure is 408 ft (124.4 m) long and 33 ft wide. If it were closed, the detour would be 19.3 mi (31 km).

Location

Open in Google Maps
CarriesGrayson Road
CrossesLaird Slough
Location3.1 MI N/E State Route 33
RouteCounty Highway 0
CountyStanislaus County
StateCalifornia
Coordinates37.56258, -121.15283
Functional classRural Major Collector

Condition and inspection

Fair

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

ComponentRatingMeaning
Deck7 GoodSome minor problems.
Superstructure7 GoodSome minor problems.
Substructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Channel and channel protection8 Very GoodNo problems noted.
Last inspectionOctober 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour within limits of footing or piles
Structural evaluation5: Somewhat better than minimum adequacy to tolerate being left in place as is
Deck geometry4: Meets minimum tolerable limits to be left in place as is
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating53.2 US tons
Inventory rating41.1 US tons

Structure

Structure typeTee Beam
MaterialConcrete Continuous
DeckConcrete, cast-in-place
Main spans3 (+9 approach)
Design loadHS 20
Structure length408 ft (124.4 m)
Longest span60 ft (18.3 m)
Deck width33 ft (10 m)
Roadway width32 ft (9.8 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic5,299 (2019)
Projected traffic6,883 by 2040
Trucks26%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed19.3 mi (31 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 Grayson Road over Laird Slough built?

It was built in 1962, making it 63 years old in 2025.

What condition is Grayson Road over Laird Slough 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 October 2023.

How much traffic does Grayson Road over Laird Slough carry?

About 5,299 vehicles per day (2019 count), of which roughly 26% are trucks.

How long is Grayson Road over Laird Slough?

The structure is 408 ft (124.4 m) long with a longest span of 60 ft (18.3 m) and a deck 33 ft wide.

Who owns Grayson Road over Laird Slough?

It is owned by the County Highway Agency.