The contract approved Wednesday would pay for transportation, sanitation, security and other costs for the party, when about 125,000 people are expected to walk from Oakland to San Francisco over the Bay Bridge.

The new eastern span will connect Oakland to Treasure Island and replace a structure that was damaged during the 1989 Loma Prieta earthquake

The contract with Hartmann Studios of Richmond must be approved by the Metropolitan Transportation Commission later this month.

"When you invite the public, the price goes way up," Berkeley Mayor Tom Bates, a member of the MTC, told the San Francisco Chronicle. "I think it's money well spent."

Transit officials want to make sure they're prepared for potentially huge crowds. They point to the 1987 celebration of the Golden Gate Bridge's 50th anniversary, when officials expected only 50,000 people to walk the bridge.

"They didn't spend any money, and 800,000 people showed up," said MTC spokesman Randy Rentschler. "We can't have that; we need to spend this money to control the crowd."

A group called the Bay Bridge Alliance is working to raise private funds for other Labor Day events, including a bike ride, half marathon, fireworks show and a Treasure Island concert. If the group gets more donations than those events require, the extra money could be used to offset some of the public funding, alliance President Bobby Winston said.

But at least one commissioner is concerned about spending so much money on the celebration.

"I think I'm going to be uncomfortable supporting this without some clear direction for sponsorship to offset what really is a taxpayer commitment," said Santa Clara County Commissioner Dave Cortese, who is also a MTC member.