<p>In this photo taken April 11, Bay Area Rapid Transit (BART) mechanic Doug Isonio works on parts for a BART train during a tour of the BART Maintenance Yard in Hayward, Calif. Driven by high gas prices and an uncertain economy, Americans are turning to trains and buses to get around in greater numbers than ever before. The aging trains and buses they're riding, however, face an $80 billion maintenance backlog that jeopardizes service just when it's most in demand.<…

April 17, 2012