US Bridges

Fourth ST over China Basin

Fair

San Francisco County, California · S of Berry ST · Structure no. 34C0027

Built
1917
108 years old, rebuilt 2005
Condition
Fair
inspected December 2024
Type
Movable - Bascule
Steel
Length
191 ft
1 main span
Daily traffic
20,000
2017 count
Owner
County
County Highway Agency

About this bridge

Fourth ST over China Basin is a steel movable - bascule carrying Fourth ST over China Basin in San Francisco County, California. It was built in 1917 and reconstructed in 2005, so it is 108 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 6 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 20,000 vehicles a day, roughly 20% of them trucks, projected to reach 30,707 by 2042. The structure is 191 ft (58.3 m) long and 44 ft wide. If it were closed, the detour would be 1.2 mi (2 km).

Location

Open in Google Maps
CarriesFourth ST
CrossesChina Basin
LocationS of Berry ST
RouteCity Street 0
CountySan Francisco County
StateCalifornia
Coordinates37.77492, -122.39204
Functional classUrban Other Principal 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
Deck6 SatisfactoryStructural elements show some minor deterioration.
Superstructure6 SatisfactoryStructural elements show some minor deterioration.
Substructure6 SatisfactoryStructural elements show some minor deterioration.
Channel and channel protection8 Very GoodNo problems noted.
Last inspectionDecember 2024
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour within limits of footing or piles
Structural evaluation6: Equal to present minimum criteria
Deck geometry4: Meets minimum tolerable limits to be left in place as is
Waterway adequacy8: Equal to present desirable criteria
Approach roadway alignment7: Better than present minimum criteria
Operating rating59.6 US tons
Inventory rating35.7 US tons

Structure

Structure typeMovable - Bascule
MaterialSteel
DeckOpen grating
Main spans1 (+6 approach)
Design loadHS 20
Structure length191 ft (58.3 m)
Longest span95 ft (29 m)
Deck width44 ft (13.5 m)
Roadway width40 ft (12.1 m)
Vertical clearance over deck18 ft (5.6 m)

Traffic and service

Average daily traffic20,000 (2017)
Projected traffic30,707 by 2042
Trucks20%
Lanes on structure3
Traffic directionTwo-way traffic
CarriesHighway and railroad
CrossesWaterway
Detour if closed1.2 mi (2 km)
TollOn a free road
National Highway SystemYes

Ownership and planned work

OwnerCounty Highway Agency
Maintained byCounty Highway Agency
Historic statusEligible for the National Register of Historic Places
Work proposedNone recorded
Estimated improvement cost—
NavigationNavigation control on waterway (bridge permit required)

Frequently asked questions

When was Fourth ST over China Basin built?

It was built in 1917, making it 108 years old in 2025. It was reconstructed in 2005.

What condition is Fourth ST over China Basin 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 December 2024.

How much traffic does Fourth ST over China Basin carry?

About 20,000 vehicles per day (2017 count), of which roughly 20% are trucks.

How long is Fourth ST over China Basin?

The structure is 191 ft (58.3 m) long with a longest span of 95 ft (29 m) and a deck 44 ft wide.

Who owns Fourth ST over China Basin?

It is owned by the County Highway Agency.