It's starting to sound to me like there is some pretty solid proof. Horses are very solid animals.
It's possible that the theories about the water supply are a fact. Maybe they're giving us some kind of experimental drug that heightens latent psychic abilities. Hell, maybe they're just trying to open up a wormhole in secret somewhere around here and it's causing some kind of weird, universal overflow.
The more important question to me is... is it happening to us because we're here, or are we here because it's happening to us? I don't know about you, but I had a few internship options and I chose a crappy one here, just because it felt right.