The Wachusett Reservoir is the second largest body of water in the state of Massachusetts. It is located in central Massachusetts, northeast of Worcester. It is part of the water supply system for metropolitan Boston maintained by the Massachusetts Water Resources Authority (MWRA). It has an aggregate capacity of and an area of almost 7 square miles (18.2 km²). Water from the Wachusett flows to the covered Norumbega Storage Facility via the Cosgrove Tunnel and the MetroWest Water Supply Tunnel. The reservoir has a maximum depth of 120 feet (36.5 m) and a mean depth of 48 feet (14.6 m).