A good way for just about anyone to reference this is to use telephone poles. A common or "typical" pole spacing that you see in your average residential neighborhood, (more so down here in the busy suburbs than up north) is 130' +/-. So, if you take a look at that next time you are out in your car or for a walk - and get familiar with it - you will have a good idea of what it is. Throw some common sense and courtesy into the mix and we will have a much safer (and friendlier) lake just by doing something that simple.