Between its reservoirs, lakes and 6,200 miles of pipes, aqueducts, and tunnels, the NYC water system is considered a marvel of modern engineering. For those of you thinking about becoming engineers, one of the great achievements of this system is that nearly all of it uses gravity to move water south. There are very few pumping stations. The tunnel that passes through OSR starts 200 feet below the Pepacton Reservoir and then descends another 1,400 feet where you are standing, enabling the water to flow unassisted.