BART directors Thursday discarded the idea of raising the base fare, acknowledging that strikes and breakdowns have tortured riders. But the transit agency is still studying the possibility of peak-hour premiums....

Last spring, well before BART's current labor strife had begun, Director Joel Keller suggested raising the $1.75 base fare, which covers rides of up to 6 miles. That fare is the least-expensive among Bay Area transit agencies and is tied with the WestCAT bus system in west Contra Costa County.

But on Thursday, BART directors discussed potential fare changes, and agreed it was the wrong time to boost the base fare, which applies to about 70,000 of the transit agency's 400,000 weekday trips....

BART officials are preparing to look into peak-period fares - charging higher prices during the busiest hours or at congested stations - a system that is used by other agencies, including the Metro system in Washington, D.C., which also operates in the city and suburbs. Carter Mau, BART's budget and planning manager, said much more analysis is needed on how a peak-period premium fare might work.