George, there must be a pretty good vegetative barrier between the lake and the majority of the dairy farms, or there could be big trouble in the lake. The uncontrolled run-off from a single dairy farm can devestate a pond/lake or stream... multiple farms would obviously be worse. So the farmers in that area are certianly doing something right as have the planners involved.
A small stream in my home town was wiped out by the accidental, (Ya right), release of liquified cattle waste into it from an outdoor storage tank. The stream is now devoid of fish life.
Now that little bit said, as long as their is sufficient vegetation and not to much of a slope between the coop and the pond I think you should be alright Rev. But certainly if you can convince your neighbour to position the coop further away it would be better. Even the feathers like Robert says could carry disease or at very least be annoying. (P.S. Just imagining the smell of a full chicken coop in the midday sun of August makes me glad not to work on a farm anymore.)
