Back in the 1990s, one of the primary aqueducts that delivers water to New York City sprung a leak. It was a pretty bad leak, evidently, as ever since then, some 35 million gallons of water have seeped out of the conduit daily. That's more than 12 billion gallons each year. God knows how many delicious bagels remain unboiled as a result.

Seeking to address this travesty, the NYC Department of Environmental Protection launched a $1 billion repair project in 2013, known as the Delaware Aqueduct Rondout-West Branch Tunnel Repair. It involved a building a new tunnel alongside the leaky segment—located between the towns of Newburgh in Orange County and Warpinger in Dutchess County—which necessitated boring through sandstone for the past eighteen months.

Workers made it through the last few feet of bedrock this week, and Inside Edition was there to capture the glorious aftermath.

This is apparently "the largest repair project in the history of NYC’s water supply." As the video notes, the tunnel-boring machine is 2.7 million pounds and stretches 470 feet long—big enough that workers can literally stand inside the drill's teeth.

According to the city, the aqueduct will be shut down and "unwatered" beginning in 2020, at which point the bypass tunnel will be connected to the existing tunnel. That stage of work is expected to take between 6 and 15 months. has more on the general awesomeness of the task at hand:

The aqueduct measures 13.5ft to 19.5ft in diameter, runs as deep as 1,500ft and is currently the world’s longest continuous tunnel. It is concrete-lined and was constructed by drilling and blasting...

The connection of the new tunnel to the existing tunnel will involve excavation of additional rock to break through to the existing tunnel. Two plugs will be installed to isolate the existing leaking portion of the tunnel. A connection chamber will be excavated and lined at the two connection points, and each of the construction shafts will be plugged. The final stage of the project will involve repair works to the existing tunnel by injecting grout into the affected areas.

Want more videos of gargantuan tunnel-boring machines triumphantly cutting through the Earth's basement? Of course you do.