The Longest Tunnel in the World Is Being Fixed Under Newburgh

600 feet below Newburgh, NY, construction workers are repairing the longest tunnel on planet earth.

In a story that sounds more like science-fiction than real life, a project that has taken more than twenty years to research and plan may finally be coming to an end right beneath our feet.

The Delaware Aqueduct in the Hudson Valley, NY

The Delaware Aqueduct is the longest tunnel in the world, and supplies roughly half of New York City's water supply every single day. Beginning at the Rondout Reservoir in Ulster County, NY and travelling underground (sometimes as deep as 1,500 feet) to Yonkers, NY, the breathtaking tunnel needs to be seen to be believed (below).

Leaks in the Delaware Aqueduct

The aqueduct began flowing in 1944, but inspections in the early 1990s revealed something troubling: there were leaks in the tunnel that contributed to more than 30 million gallons of drinking water escaping the aqueduct daily.

Billion-Dollar Project to Repair Delaware Aqueduct in the Hudson Valley

Further research revealed that the majority of the water loss was happening at a specific location of the tunnel underneath Newburgh, NY. This spawned a massive $1 billion project to create a 2.5-mile "bypass tunnel" that would skirt the affected areas and restore more efficient water delivery to New York City.

The New Delaware Aqueduct Bypass Tunnel in Newburgh, NY

Images (below) show the construction of the new bypass tunnel, which was created 600 feet underground between Newburgh in Orange County, NY and the Town of Wappinger in Dutchess County, NY. Soon, the aqueduct will be drained and the final stage of the project will begin.

Officials say the scale of the project is so large that planning has been underway for roughly two decades. Information including water levels, projected rainfall, and more will all be taken into consideration before the shutoff to ensure that millions of New Yorkers will not be cut off from their water supply. Currently, the shutoff is expected to be in effect between October 2024 and June 2025. 

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During the shutoff, other watersheds such as the Croton System will be utilized at full capacity in order to maintain New York City's water supply. Currently, recreational activities on related reservoirs remain unaffected.