New York City's water supply system is the largest municipal water supply system in the United States. This modern marvel of engineering consists of 19 reservoirs and 3 lakes that store 570 billion gallons of water when full, delivering that water through 400 miles of aqueducts to 8.5 million people in New York City and another 1 million people in 72 communities throughout the Hudson Valley - by gravity alone. This system shaped the design of older neighborhoods in New York City - the powerfu...