The tens of thousands of people who take Metro shuttles to Huskies football games, Mariners games and city festivals may soon be paying private shuttles to do the work under new charter rules approved by the Federal Transit Administration.

Under the new policy, which took effect May 1, Metro must solicit bids from private bus-charter agencies for all sports and cultural events. Only if no one bids could Metro continue to provide the service.

"Private operators have said it's unfair that taxpayer dollars are being used to provide service at a lower cost," Metro's general manager Kevin Desmond said Friday.

Last year, the University of Washington paid Metro $500,000 to carry 187,000 Huskies fans to seven home games on 180 buses, the largest Metro shuttle effort. Riders rode the buses for free because of the UW subsidy.

Metro carried 66,000 Mariners fans last year, 33,000 people to the Seafair hydroplane races and 53,000 to Seahawks games.

Shuttles also were provided to other destinations such as Bumbershoot, the Folklife Festival, Emerald Downs and the Flower and Garden Show.