load a full kask of gunpowder into one diving suit, with the oxygen turned on.load the legs with stone. add a form of light that can be seen from 130 feet under water ,drop from a boat above the shipwreck.
cast lightning bolt at the target from above. BOOM!
Hmm, how deep was the water?
The depth of the water near the wreck is about 120′ (the shaft down to the tram station is 100′ and the station itself 30′, but the tower sits on a rise about 10′ above the waterline).
Maximum distance for vision is 100′, but roughly half that if you are looking straight down — you could see a light source beyond that 50′ limit, though. Keep in mind that underwater distances are measured like indoor distances using feet instead of yards for spells, movement, and missile attacks; also, lightning bolt detonates in a sphere with a 20′ radius rather than manifesting as a narrow but long bolt.
i might be worried the explosion if it worked would collapse the tunnels.we should probably just make the swim to the tunnel extension and see whats there first.