A second surge tower was toppled at a defunct Campbell River generating station Thursday.

Explosives were strapped on to the 90-metre tower near the old John Hart Generating Station and it came crashing down in a controlled explosion.

BC Hydro brought down the first tower last week.

They towers, once the largest structures on Vancouver Island, were erected back in the late 1940s and early '50s to help protect water penstocks from pressure changes.

The third remaining tower will stay put as it holds valuable communication equipment and serves as a beacon for the local airport, according to BC Hydro.