There's a massive tunnel being dug under the Hudson Valley, but why? The answer comes down to one thing, and that's water.

Basically, one of the main sources of water to New York City has sprung a leak, two in fact. In order to fix those leaks, they need to stop water from going through what's called the Delaware Aqueduct. In order to do that, they must build at 2.5-mile bypass tunnel so they can properly fix the problems. More than 30 million gallons have reportedly been leaking daily since the 90s.

The Delaware Aqueduct Bypass Tunnel as it's known runs 600 feet under the Hudson River from Newburgh to the Town of Wappinger. They began drilling in 2017 and are nearly 70% done with that part of the job. The $1 billion project is scheduled to be completed in 2023 and is on time and on budget according to a recent press release.

From the NYC Watershed Facebook page:

Workers inspect and install rebar for the tunnel that will connect the bypass to the existing Delaware Aqueduct.

Photo By: NYC Watershed/Kristen Artz

As the tunnel boring machine continues to excavate about 600 feet under the Hudson River, workers are already preparing to make the connections between the new tunnel and the existing Delaware Aqueduct. The work in this photo is for the eastern connection, under the Town of Wappinger in Dutchess County.

Photo By: NYC Watershed/Kristen Artz

Something you might not recognize in this photo? DEP has taken every step to ensure this tunneling project minimizes the production of greenhouse gases. A small but important part of that is lighting. It's the first tunneling project in North America to use only LED lights.

Photo by: NYC Watershed/Kristen Artz

What lies beyond that wall? The tunnel boring machine, which is excavating the new tunnel, is about 3,000 feet beyond this wall. The machine, named Nora, is unique and huge. It is 21.6 feet in diameter, 470 feet long, and weighs 2.7 million pounds.

Photo by: NYC Watershed/Kristen Artz

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