 At in length, it is one of the longest aqueduct tunnels in the world being mile (0.8 km) shorter than the Hetch Hetchy Aqueduct.Water from the capacity Quabbin Reservoir flows through the Quabbin Aqueduct from the northeast side of the Quabbin, up a slope to the Ware River Diversion in South Barre, Massachusetts, down again to the Wachusett Reservoir, and then through a power station near the Oakdale section of West Boylston, Massachusetts.This upward and downward flow occurs by natural siphon action, with the high point in the siphon being at the Ware River Diversion.