BART is changing service for tonight, affecting passengers going between downtown San Francisco and the East Bay.

BART will run trains later than usual tonight and Friday morning for New Year's Eve, but trains bound for the East Bay will not stop at all stations in downtown San Francisco in an effort to ease overcrowding at the Embarcadero Station.

In past years, large crowds attending the downtown fireworks show have caused overcrowding at the Embarcadero BART station.

As a result, trains on the Pittsburg/Bay Point and Richmond lines will not stop at the Embarcadero station beginning at 8 p.m. on New Year's Eve. People wishing to go to the fireworks show on those lines will have to get off at the Montgomery station, according to BART officials.

Trains on the Dublin/Pleasanton and Fremont lines will stop at the Embarcadero station, but not at the Montgomery station.

Trains headed to Millbrae, SFO or Daly City will make all stops in San Francisco on New Year's Eve and into New Year's Day, according to BART officials.

Additional "event" trains will also be standing by to take riders during the busiest time of the night after the fireworks end shortly after midnight.

BART service will last until 3 a.m. Friday to help riders get home from festivities around the Bay Area. It will begin again at 8 a.m. Friday and will operate on a holiday/Sunday schedule.

BART officials recommend that riders buy a round-trip ticket before starting a trip to avoid lines at ticket machines on the way home.

During a news conference, BART officials showed clips from previous New Year's Eves that highlighted the need to implement these service changes.

BART officials said that they will go all out to try to deter potentially rowdy revelers from engaging in unruly behavior on New Year's Eve and to try to keep their trains moving in an efficient manner.

At a BART board meeting, Cmdr. Daniel Hartwig said, "We will have over 200 police personnel within our system" to keep crowds under control.

Hartwig said as many as 125 BART police officers will be on duty and they will be joined by deputies from the sheriff's departments in Alameda and San Francisco counties. Contra Costa County sheriff's deputies may also help out, he said.

Dan McMenamin, Bay City News, contributed to this report.

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