Elon Musk Touts Cheaper Tunneling Costs for LA Transit

Got story updates? Submit your updates here. ›

Elon Musk has amplified a claim on X (formerly Twitter) that his Boring Company could dig underground tunnels in Los Angeles for far less than the costs of the city's planned subway expansions. While LA Metro's Purple Line Extension is estimated to cost around $1 billion per mile, Musk says his tunneling technology could deliver similar infrastructure for a fraction of the price, though the systems would be designed for electric vehicles rather than high-capacity trains.

Why it matters

Musk's comments reignite an ongoing debate over the future of transit in Los Angeles, where the city is investing billions in new rail lines to address traffic and mobility challenges. If Musk's claims hold true, it could disrupt traditional approaches to urban infrastructure development and prompt a re-evaluation of tunneling as a potentially cheaper and faster alternative to above-ground rail.

The details

Los Angeles is nearing completion of the roughly 9-mile Purple Line subway extension, which is estimated to cost around $9.5 billion or $1 billion per mile. The city also has plans for the even more ambitious Sepulveda Transit Corridor, a fully underground line beneath the Santa Monica Mountains that is projected to cost $20-25 billion for 12-14 miles of track. In contrast, Musk's Boring Company has promoted plans to dig highway tunnels in Nashville for $240-300 million over 10-13 miles, a tiny fraction of typical subway costs. However, Boring's tunnels are designed for electric vehicles, not high-capacity trains, limiting passenger throughput compared to heavy rail.

• The Purple Line Extension in Los Angeles is nearing completion.
• The proposed Sepulveda Transit Corridor is projected for service in the late 2030s or early 2040s.

What’s next

Musk's claims about the Boring Company's tunneling costs and capabilities will likely continue to be scrutinized as Los Angeles moves forward with its ambitious subway expansion plans. The viability of tunneling as an alternative to traditional rail transit remains an open question that will require further evaluation.