US Bridges

Messick Road over Mosher Slough

FairPosted for load

San Joaquin County, California · 0.6 MI W of Clements RD · Structure no. 29C0274

Built
1931
94 years old
Condition
Fair
inspected February 2025
Type
Stringer/Multi-beam or Girder
Wood or Timber
Length
51 ft
3 main spans
Daily traffic
150
2019 count
Owner
County
County Highway Agency

About this bridge

Messick Road over Mosher Slough is a wood or timber stringer/multi-beam or girder carrying Messick Road over Mosher Slough in San Joaquin County, California. It was built in 1931, so it is 94 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. Its operating status is: posted for load restriction.

It carries about 150 vehicles a day, roughly 10% of them trucks, projected to reach 214 by 2045. The structure is 51 ft (15.5 m) long and 20 ft wide. If it were closed, the detour would be 2.5 mi (4 km).

Location

Open in Google Maps
CarriesMessick Road
CrossesMosher Slough
Location0.6 MI W of Clements RD
RouteCounty Highway 0
CountySan Joaquin County
StateCalifornia
Coordinates38.05224, -121.08749
Functional classRural Local

Condition and inspection

Fair

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

ComponentRatingMeaning
Deck6 SatisfactoryStructural elements show some minor deterioration.
Superstructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Substructure5 FairAll primary structural elements are sound but may have minor section loss, cracking, spalling or scour.
Channel and channel protection7 GoodSome minor problems.
Last inspectionFebruary 2025
Inspection intervalevery 12 months
Operating statusPosted for load restriction
ScourUnknown foundation; not evaluated for scour
Structural evaluation5: Somewhat better than minimum adequacy to tolerate being left in place as is
Deck geometry3: Basically intolerable, requiring high priority of corrective action
Waterway adequacy7: Better than present minimum criteria
Approach roadway alignment6: Equal to present minimum criteria
Operating rating25.4 US tons
Inventory rating17.9 US tons

Structure

Structure typeStringer/Multi-beam or Girder
MaterialWood or Timber
DeckWood or timber
Main spans3
Design loadUnknown
Structure length51 ft (15.5 m)
Longest span19 ft (5.9 m)
Deck width20 ft (6.2 m)
Roadway width20 ft (6 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic150 (2019)
Projected traffic214 by 2045
Trucks10%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed2.5 mi (4 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 Messick Road over Mosher Slough built?

It was built in 1931, making it 94 years old in 2025.

What condition is Messick Road over Mosher 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 February 2025.

How much traffic does Messick Road over Mosher Slough carry?

About 150 vehicles per day (2019 count), of which roughly 10% are trucks.

How long is Messick Road over Mosher Slough?

The structure is 51 ft (15.5 m) long with a longest span of 19 ft (5.9 m) and a deck 20 ft wide.

Who owns Messick Road over Mosher Slough?

It is owned by the County Highway Agency.