I've noticed some boats at my marina give you a shock when you touch the rigging cables. Feels like a static electricity type of shock. Is this normal? In other words, does static electricity build up on a boat or are these boats being charged by some kind of electrical current leak into the water from the shore power. It doesn't happen on my boat but friends boats always seem to shock me when I touch them. None of us have our boats plugged into shore power but power is available at each slip. Basically, I'm worried if someone is going to get electricuted if they jump in the water near one of these boats to do repairs or bottom cleaning. Anyone know anything about this?