Since Kate's a female engineer with a massive terrorist problem on her hands, you won't just have to survive the water (a feat in itself) but learn to control it. Got an enemy guarding the way? Why not remotely open a door, unleashing a forceful wave that brushes them away. You could also use the water to disguise a mine. But our favourite, which demonstrates the options for combining objects you'll come across, is this: stuffing a rubber duck full of semtex, you can place it on the water. Set it in the right place, and it'll be taken downstream by the current, hopefully towards an enemy. Catch his eye and he'll approach it. And the rubber duck will blow his face off. Nicely done.
So the water can be your friend, but it can also your enemy, or more specifically, Kate's. Whenever she's in real danger her phobia kicks in and the screen will start to blur in monochrome, operating her will become more difficult and it may even move to first-person mode. By making her safe, and by using judgement to intelligently dispose of enemies and solve puzzles, you'll keep her calm and you in control.
And as if her fear, a sinking ship, water throwing objects violently through the boat and a ton of ideologically-driven, ruthless mercenaries weren't enough to contend with, something also goes wrong with Nano Cell's nanobots. Once they're released into the watery environment, they begin to group together, become sentient, smarter, and dangerous. Want more? Check back here for the inside line.