Watch MegaStructures Season 5 Episode 12 Online

A team of experts mobilises to demolish, excavate and recycle a 25,000 ton dam built of concrete and steel. The pressure is on: they have just half the time needed to complete the job. Worse yet, their biggest challenge stands behind the old dam – one million cubic yards of boulders, gravel and sand that the river has stacked against it for nearly a century. To remove this blockade, the team gambles on a radical, dangerous plan that's never been tried before: turning the energy of a perfect storm against the debris. If they are not successful, a generation of endangered salmon returning to spawn may be wiped out.