4.5 for engaging scientific reporting. This author told a very complex tale about the largest freshwater system in the world in a way that was interesting to read but not too textbooky. He looked at things from all sides with little bias, delved into strange yet applicable historical events, and explained convoluted politics and laws. The author also did a great job in showing the reader how the immense geography, hydrogeology, and biology of it affects not only the Great Lakes Watershed, but states and entire countries around it. This book gave me a lot to think about. It was painful to read at times because of the mistakes some humans have made there, but it was very thought-provoking. I definitely suggest this book to anyone that lives near the Great Lakes or in a place with threatened water security, anyone that likes learning about biology, environmental science and public law, pesticides, or town planning.