An 85-mile tunnel carries water from upstate New York reservoirs to New York City. It leaks a lot, and it is finally being repaired.
New York City relies on vast reservoirs in upstate NY to supply its water. These reservoirs were created by flooding dozens of upstate towns and hamlets, displacing thousands of citizens and the graves of thousands more. The process by which the towns were taken by eminent domain and the lasting impact on the affected areas is chronicled in the meticulously researched book Nineteen Reservoirs: On Their Creation and the Promise of Water for New York City.
The heart of this system is the Delaware Aqueduct. At 85 miles long, it is the longest tunnel in the world and supplies 1.3 billion gallons of water daily. However, it also leaks 35 million gallons daily and has been leaking for decades. In addition to wasting billions of gallons of water, the leaks cause homes hundreds of feet above the aqueduct to suffer flooded basements and overflowing wells and septic tanks.
The New York City Department of Environmental Protection oversees the system and has constructed a bypass tunnel where the aqueduct runs under the Hudson River. Beginning in October, the entire Delaware Aqueduct will be shut down for six months to connect the new bypass. During the shutdown, the tunnel will undergo other repairs and maintenance. The reservoirs on the other aqueducts will be filled before the shutdown to ensure sufficient supply during the repairs.
Previously: Remarkable photos of Greek tunnel construction