Until the advent of the industrial revolution, the Great Lakes- Lakes Superior, Huron, Michigan, Ontario, and Erie- were self contained and held the majority of the world's fresh water.

Dan Egan in his Pulitzer finalist The Death and Life of the Great Lakes has exposed how science and history have wrought change on the once cleanest, freshest bodies of water in the world. While zebra mussels are only one issue affecting the future of the Great Lakes today, the species is hardly the only living being or environmental change that could affect the future of the Great Lakes in the century to come. Lake Michigan is part of the Great Lakes, the largest freshwater source in the world, and to me, the water still tastes crystal clear, until this past summer when it did not, and I reluctantly joined her in drinking filtered water. For years my mother has refused to drink tap water claiming that zebra mussels have affected the taste of her water supply.