Smithsonain Ch. - Impossible Repairs Series 1 Part 6: Big City Tunnel Boring (2021) 1080p HDTV x264 AAC MVGroup

The crew is heading under one of the world's largest lakes for a multi-million-dollar tunnel-boring project. The crew's mission: to give Toronto's wastewater system a major upgrade, using a highly sophisticated machine capable of creating a tunnel with a diameter greater than a two-story house. But big machines often require big repairs. Witness the epic battles happening 260 feet below the Earth's surface as our hard-hat hero’s battle challenge after challenge to keep this operation running on budget and on schedule.