If the utilities aren't working at your squat, get a sillcock key at a hardware store. Pretty much every building that's not a house has a sillcock at the back of it. You can turn it on with the key, fill up a bucket of water and take it home. DO THIS ONLY AT NIGHT! If you get caught, well, it's pretty much illegal. Not to mention you foul the neighbourhood for other tramps. So, yeah, be quiet and don't get greedy and you can have free water for your showers. It's also good to drink.