> ONTARIO, Calif.—The unsolicited proposal from Elon Musk’s tunnel-building venture arrived in January 2020. To the local transportation authority, it felt like finding Willy Wonka’s golden ticket.
> Officials had started planning for a street-level rail connection between booming Ontario International Airport and a commuter train station 4 miles away, with an estimated cost north of $1 billion. For just $45 million, Mr. Musk’s Boring Co. offered to instead build an underground tunnel through which travelers could zip back and forth in autonomous electric vehicles.
> Dazzled by Boring’s boasts that it had revolutionized tunneling, and the cachet of working with the billionaire head of EV maker Tesla Inc., the San Bernardino County Transportation Authority dumped plans for a traditional light rail and embraced the futuristic tunnel.
> When it came time to formalize the partnership and get to work, Boring itself went underground—just as it has done in Maryland, Chicago and Los Angeles. Boring didn’t submit a bid for Ontario by the January 2022 deadline.
> The six-year-old company has repeatedly teased cities with a pledge to “solve soul-destroying traffic,” only to pull out when confronted with the realities of building public infrastructure, according to former executives and local, state and federal government officials who have worked with Mr. Musk’s Boring. The company has struggled with common bureaucratic hurdles like securing permits and conducting environmental reviews, the people said.
> “Every time I see him on TV with a new project, or whatever, I’m like: Oh, I remember that bullet train to Chicago O’Hare,” said Chicago Alderman Scott Waguespack. Boring had backed away from its proposal for a high-speed tunnel link to the airport there.
> Mr. Musk and Steve Davis, president of Boring, didn’t respond to requests for comment.