[0.E.O]

The story says they were trespassing. That would imply that there were fences or keep-out signs or something like that that they ignored. Is that the case? Were these people somewhere that they knew they shouldn’t be? Or is it a big body of water in a rural area and they might skate on the charges because they could say they didn’t know?

[St_Thomas_Aquinas]

It's a huge reservoir in central Mass, which supplies the drinking water for Greater Boston. It appears that they passed "No Trespassing" signs. I suppose that they could plead ignorance.