From Chicago City Hall to Tokyo’s Imperial Hotel, green roofs are growing fast. They’ve been well established in Europe for years, and now have taken hold in the United States, with millions of square-feet of green roofs installed or in process since the early 2000s.
At the same time, growing development in U.S. cities is leading to increased levels of pollution. A main area of concern is the polluting of one of our most valuable resources: water.