Lake Ontario is quite small, with a length of approximately 311
km (193
mi), and a breadth of 85 km (53 mi). If not for a greater
average depth (283 feet, giving it nearly 393
cubic miles to Erie's 116), it would be most equal to
Lake Erie where volume is concerned, as the two are quite similar in size with Erie coming out just ahead in both length and breadth. Given the volume of Lake Ontario, it's not too entirely surprising that the
drainage basin covers a fairly large portion of Ontario as well as bits of
New York, and extends as far down as
Pennsylvania. There is a much greater population on the Canadian shores of the lake (there is about 726 miles of
shoreline all together), as opposed to the U.S. side, and there is also an abundance of farming and
industrialization on Canadian soil in the area.
The problem with this great lake is that it happens to be the last in the chain, and thusly, ends up
accumulating pollution from all of the others before it. Sadly, it is no longer the cleanest lake, perhaps even the worst off at this point.
info gathered throughout high school geography classes, as well as, more recently, www.great-lakes.net.