Work on the new eastern span of the Bay Bridge has "reached its last major milestone" and "we can smell the finish line," Metropolitan Transportation Commission Executive Director Steve Heminger said Tuesday.

At a news briefing at a Caltrans office in Oakland near the Bay Bridge, Heminger said with the recent successful completion of a complex process called a "load transfer," the new $6.3 billion span remains on schedule to open on Labor Day weekend next year.

Heminger said the transfer was a three-month process in which workers lifted 35,200-ton bridge decks from the temporary steel trestles where they were assembled onto the tower and main suspension cable that cradle and support the self-anchored suspension span, a 2,047-foot section of bridge east of Yerba Buena Island.

The weight of the bridge is now supported by a single, one-mile-long cable that acts like a sling, he said.

The design of the new eastern span is unusual because the cables of traditional suspension bridges are anchored into the ground on either end, Heminger said.

"The new bridge is supporting itself and is functioning as a self-anchored suspension bridge so there's a pretty big collective sigh of relief by the engineers," Heminger said.

He described the remaining tasks to be completed before the new span opens next year as "meat and potatoes work" such as roadwork, striping of lanes and mechanical and electrical work.

In completing the new span, "We're unwrapping a gift for our region that will last 100 years or more," he said.

Caltrans spokesman Bart Ney said the self-anchored suspension span is the longest span of its kind in the world and is the signature element of the new eastern portion of the bridge.