I-280 Construction: Busy Stretch of Interstate 280 Near AT&T Park Closed to Traffic Memorial Day Weekend

Southbound 280 will be closed from downtown SF to Pennsylvania Avenue on-ramp beginning May 22 at 9 p.m. until Tuesday morning

A busy stretch of Interstate 280 near AT&T Park in San Francisco will be closed, starting Thursday night and continuing through the Memorial Day weekend.

That means traffic in the City will be worse than usual, especially if you plan on heading to a ballgame.

The California Department of Transportation will close southbound Interstate 280 from downtown San Francisco to the Pennsylvania Avenue on-ramp.

The construction will start Thursday night at 9 p.m. and will continue until Tuesday morning at 5 a.m.

Southbound on-ramp closures include:

  • Mariposa Street/18th Street on-ramp
  • 6th Street/Brannan on-ramp
  • King Street on-ramp

Alternatives: In general, southbound I- 280 traffic will detour to U.S. 101. Mariposa Street/18th Street traffic can also detour to the southbound I-280 Pennsylvania Avenue on-ramp.

DOT says the closure is necessary in order to replace a bridge hinge on southbound I-280, making it seismically sound. Workers will have to demolish a portion of the freeway and then rebuild it in order to swap the hinge out.

Northbound I-280 will remain open over the Memorial Day Holiday weekend.

More closures are planned for the Fourth of July and Labor Day holiday weekends to replace bridge hinges on the northbound side of I-280.

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