I live in the foothills of the Blue Ridge Mountains with several large man-made mountain lakes. The boat docks have an electrical difference from the lake water, thus, folks get shocked when in the water, and touch the metal structure floating above the water when they try to exit the lake. This seems to be caused by the poor grounding at the homes that supply power to the docks, and by the use of metal conduits and boxes that require grounding to the electrical source. Stray voltages enter the grounds at the home, travel to the dock, and when a person completes the circuit into the lake water; they do get shocked. To eleminate this problem, I always use plastic (PVC) on docks. But even this is no good at times due to the3 neighboring dock having direct contact into the water by anchor cables, metal ladders, etc. These lakes are for electrical plants; one of which is a nuclear power plant. This nuclear station is often the blame for the stray voltage in the lake, but I am convienced it is not the water, but the docks. Electricians need better education in this area (self included).