US Bridges

DR Mlk Jr Blvd over Mormon Slough

Good

San Joaquin County, California · 0.3 MI East of Mariposa · Structure no. 29C0431

Built
1949
76 years old, rebuilt 1986
Condition
Good
inspected January 2025
Type
Slab
Concrete Continuous
Length
118 ft
7 main spans
Daily traffic
12,500
2017 count
Owner
City
City or Municipal Highway Agency

About this bridge

DR Mlk Jr Blvd over Mormon Slough is a concrete continuous slab carrying DR Mlk Jr Blvd over Mormon Slough in San Joaquin County, California. It was built in 1949 and reconstructed in 1986, so it is 76 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 12,500 vehicles a day, roughly 25% of them trucks, projected to reach 20,498 by 2045. The structure is 118 ft (36 m) long and 44 ft wide. If it were closed, the detour would be 5 mi (8 km).

CarriesDR Mlk Jr Blvd
CrossesMormon Slough
Location0.3 MI East of Mariposa
RouteCity Street 0
Coordinates37.94686, -121.25033
Functional classUrban Other Principal 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 inspectionJanuary 2025
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 geometry5: Somewhat better than minimum adequacy to tolerate being left in place as is
Waterway adequacy7: Better than present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating38.6 US tons
Inventory rating23.3 US tons

Structure

Structure typeSlab
MaterialConcrete Continuous
DeckConcrete, cast-in-place
Main spans7
Design loadHS 20
Structure length118 ft (36 m)
Longest span24 ft (7.3 m)
Deck width44 ft (13.3 m)
Roadway width40 ft (12.2 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic12,500 (2017)
Projected traffic20,498 by 2045
Trucks25%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed5 mi (8 km)
TollOn a free road
National Highway SystemYes

Ownership and planned work

OwnerCity or Municipal Highway Agency
Maintained byCity or Municipal 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 DR Mlk Jr Blvd over Mormon Slough built?

It was built in 1949, making it 76 years old in 2025. It was reconstructed in 1986.

What condition is DR Mlk Jr Blvd over Mormon Slough 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 January 2025.

How much traffic does DR Mlk Jr Blvd over Mormon Slough carry?

About 12,500 vehicles per day (2017 count), of which roughly 25% are trucks.

How long is DR Mlk Jr Blvd over Mormon Slough?

The structure is 118 ft (36 m) long with a longest span of 24 ft (7.3 m) and a deck 44 ft wide.

Who owns DR Mlk Jr Blvd over Mormon Slough?

It is owned by the City or Municipal Highway Agency.