The campaign, sponsored by the American Public Transportation Association, strives to educate residents about how riding public transportation can save money, conserve gasoline and reduce greenhouse gas emissions.
The nationwide Dump the Pump day is Thursday and more than 125 public transit agencies, including many from the Bay Area, are on board. The City Council decided to expand the effort beyond the national campaign to include today, said city spokeswoman Jan McCrea.
"If gas prices are too high for you, then dump the pump on June 18 and June 19 and take a bus or the BART instead; using public transportation systems is the quickest way to beat the high price of gas," San Leandro Mayor Tony Santos said in a statement.
Coinciding with this year's campaign, the Bay Area residents will be able to travel at no expense during the year's only free-transit Spare the Air Day on Thursday.
Spare the Air days are declared when the Bay Area is expected to have poor air quality in an effort to alert the public of health hazards and reduce the number of cars on the road.
Transit will be free Thursday on Bay Area Rapid Transit, trains and ferries until noon, and all day on buses and light-rail systems.