SAN FRANCISCO (KCBS) – A crackdown was scheduled for launch Tuesday to keep commuters from shortchanging transit agencies when using new Clipper fare cards.

KCBS’ Tim Ryan Reports:

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The transit cards allow riders to pay for a trip on Muni, BART, Caltrain and other transit agencies with just one fare card.

Several months ago, it was revealed that riders could essentially shortchange the transit agencies by adding $2.00 to one of the cards, which were being distributed free of charge, and take a ride costing more than the $2.00 loaded on the card, discard the card without making good on the negative balance, then secure a new card. For example, a commuter could take an $8.00 ride for just $2.00, cheating the system out of $6.00.

The opportunity for scofflaws to engage in such behavior, however, seemed short-lived. Beginning Tuesday, commuters would be required to add a minimum of $5.00 to a new Clipper card.

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When the Clipper fare system was first launched, there was apparently very little exploitation of this glitch. Data suggested that the overwhelming majority of commuters used their cards repeatedly, indicating that they were replenishing low or negative balances.

However, after reports surfaced about the potential to cheat the system, scofflaw activity appeared to soar.

“Approximately 80% have been used for only a single trip,” John Goodwin with the Metropolitan Transportation Commission explained the data from December 2010. “So that’s a sign of people that are gaming the system.”

However, come Tuesday, that would apparently be much harder to do.

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