You guys remember Evan Monsignac from Haiti, who survived for 27 days buried beneath the rubble? I did a little looking around and found that there have been a few articles written about him, this one I am linking here is the most descriptive. When they brought him in, we all had a hard time believing what we were hearing, but after reading the article, it makes sense and it answers the water source question.

Quite an amazing, determined and extremely lucky man.
My heart goes out to him as he is still recovering from his ordeal.

How Evan Monsignac Survived 27 Days buried alive