You have the right idea, but the player can only dash over a single water tile (or a single empty tile) before gravity takes effect, so there needs to be one more snowman pushed into the water to be allowed to reach the next screen without drowning.
There was a bug where the player's x-axis momentum was allowed to continue while drowning - I posted a small update to correct that. Longer term, I may add a message in the game over screen when this happens saying "you can only skip 1 water tile" if I can detect it (probably checking to see if player is drowning and x position is not evenly divisible by a tile width).