Elon Musk Tunnel

Elon Musk, co-founder and chief executive officer of Tesla Inc., arrives in a modified Tesla Model X electric vehicle during an unveiling event for the Boring Company Hawthorne test tunnel in Hawthorne, Calif., on Tuesday, Dec. 18, 2018. Musk unveiled his underground transportation tunnel on Tuesday, allowing reporters and invited guests to take some of the first rides in the revolutionary albeit bumpy subterranean tube — the tech entrepreneur's answer to what he calls "soul-destroying traffic." (Robyn Beck/Pool Photo via AP)

The inaugural ride in Elon Musk’s 1.14-mile tunnel prototype below an industrial park in Hawthorne, Calif., was a bumpy one, and at 53 mph much slower than predicted.

Nevertheless, having one of his electric Tesla automobiles transit the tunnel last week represented a measure of vindication for the brash, sometimes eccentric inventor.

And in the Los Angeles metro area, one of the nation’s worst for traffic congestion, it’s bound to get more than passing attention, particularly since the per-mile cost of boring the tunnel — $10 million — is a fraction of what prior subway projects have cost.

“Musk put a Tesla in a tunnel, and he did it for a potentially game-changing price,” wrote Laura Bliss in CityLab, an online publication about urbanism. “If Musk’s company has built what many tunneling pros have long thought unachievable — a boring machine that does the job cheaper and faster than the stalwarts of civil engineering thought possible — that could be a boon for underground transit systems in the U.S., which often struggle to justify their enormous construction costs.”

The Los Angeles Times observed that Mr. Musk’s estimate didn’t include research and development costs, or the expense of buying underground right of way.

But even if the per-mile cost were as high as $50 million, CityLab notes, it would still be a bargain. As evidence, it cited the comparable costs of two Los Angeles subway projects: $800 million and $920 million a mile.

Typically, Mr. Musk has big plans for the fledgling tunnel project, with a system that includes stops at Los Angeles International Airport, the downtown train station, Dodger Stadium and the Getty Center. And he envisions its completion by 2028.

Of course, it’s worth pointing out that cars aren’t a particularly efficient way of moving people around, whether under or above-ground. Mr. Musk’s elaborate car-based prototype perplexingly combines some of the worst aspects of car and subway transportation.

Building a cheap tunnel, however, has enormous potential to help cities expand strained transit systems or build new ones to take the pressure off clogged freeways.

Mr. Musk’s critics might like to relegate his plans for a tunnel system to the realm of the improbable. And obviously there is a long way to go before it might attain practical usage.

But the Hawthorne tunnel, developed by Mr. Musk’s Boring Co., is a real achievement. It potentially sets the groundwork for more to come.