Quote: the G-man said: Well, knives as a weakness didn't bother me.
And I suppose its possible the things were simply not physically strong enough to break down a locked door.
But if water is going affect them in the same way as, basically, an acid affects a human, it makes no sense they could survive for more than a few hours without getting exposed to it and dying.
They were physical enought to do a more than twelve foot vertical leap onto a rooftop.