The Bay Area's transportation commission will take a new look at an old idea to build a new bridge across San Francisco Bay between the East Bay and the Peninsula.

Saying its mission is to look at long-term options for traffic relief, the Bay Area Toll Authority's oversight committee on Wednesday will consider authorizing a $400,000 study on the Southern Crossing Bridge between Interstate 238 in San Lorenzo and Interstate 380 in San Bruno.

Don't expect to see a new bridge any time soon, though.

There was no clamor to build the bridge after a study in 2002 estimated the price tag at $8.2 billion -- an amount likely to fall on the backs on motorists who pay bridge tolls.

"We think enough time has passed to take a new look at the project, update our information, and see if things have change since our last study," said Randy Rentschler, a spokesman for the Bay Area Toll Authority. It is a sister agency of the Metropolitan Transportation Commission, the nine-county transportation planning agency.

The money for the study would come from tolls collected on seven state-owned toll bridges in the region.

Planning consultants hired by the authority would take about six months to update technical information about the Southern Crossing bridge and alternatives for reducing traffic congestion.

The toll authority will use the study findings to decide whether to conduct a second, more detailed study with recommendations on whether to build the new bridge. One option studied eight years ago was a second BART Transbay Tube to carry more riders to and from San Francisco and the East Bay, luring more motorists onto public transit and away from rush-hour gridlock on the Bay Bridge, the most heavily used bridge in California.

Rentschler said the bridge study would examine the feasibility of developing express bus lanes or rail service on the bridge -- in addition to lanes for car traffic.

The toll authority meets at 9:30 a.m. at the MetroCenter, 101 Eighth St., Oakland. Go to www.mtc.ca.gov for more information.

Contact Denis Cuff at 925-943-8267. Read the Capricious Commuter at www.ibabuzz.com/transportation/. Follow him at Twitter.com/deniscuff.