The Professor would raise the IQ level here
This is one of those problems when part of your rogue's gallery includes Atlantean villains. The transport is wrecked, the water isn't safe - but there's no threat as long as the girls stay on the island til reinforcements arrive. Unfortunately, that could be a while.

Pippi was wet and bedraggled when she managed to crawl up on shore. She's already working to get herself back into fashionable order.

"Ok, Cait." She says, very seriously. "We're stuck on an island, maybe for a long time. So there's some very important considerations we need to figure out. So, first things... I'm Maryanne, you're Ginger."