The Delaware Aqueduct is the newest of the New York City aqueducts. It takes water from the Rondout Reservoir through the Chelsea Pump Station, the West Branch Reservoir, and the Kensico Reservoir, ending at the Hillview Reservoir in Yonkers, New York. The aqueduct was constructed between 1939 and 1945, and carries approximately half of the New York City water supply of 1.3 billion US gallons (4,900,000 m) per day. The Delaware Aqueduct leaks up to 36 million US gallons (140,000 m) per day. At 85 miles (137 km) long and 13.5 feet (4.1 m) wide, the Delaware Aqueduct is the world's second longest continuous underground tunnel after the Thirlmere Aqueduct in North West England. Since the late 1970s, the New York Department of Environmental Protection has been monitoring two leaks in the Delaware Aqueduct that collectively release between 10 and 36 million US gallons (38,000 and 140,000 m) of water per day. These leaks have caused many problems with flooding and drinking water contamination, particularly for residents of Wawarsing, New York.