When the pipes under your sink spring a leak, you call a plumber. But what does New York City do when the pipes carrying its drinking water, from the reservoir located two hour’s drive away, similarly leak?
That job calls for some something special: underwater repairmen.
Most of New York City’s water comes from the Catskills, which are located 75 or more miles northwest of Manhattan. To get the water from the Catskills into the showers, sinks, and toilets of the city’s residents, the government built huge tunnels — in the case below, one 13.5 feet wide, 1,200 feet below ground, and 45 miles (miles!) long. And this particular tunnel, called the Rondout-West Branch tunnel, is leaking.
In and of itself, the fact that this tunnel leaks is not that big of a deal — leaks are rather common. What makes the Rondout-West leak notable is the sheer magnitude of the seepage, with, as of late 2008, 20 million gallons lost on a typical day, with nearly double that on particularly bad ones. For approximately twenty years, the city’s Department of Environmental Protection (DEP) had poo-pooed the problem, but with houses in the area of the leak (located 100 miles from Manhattan) complaining of flooding, the DEP changed its tune. The solution? The aforementioned repair crew.
As reported by the New York Times, the city hired six deep-sea divers, enlisting them for a month of repairs. During this month, the divers are confined to a pressurized, 24 foot long tube (seen here), allowing them to enter the repair zone located 70 stories underwater, without having to depressurize every time. The pressurized tank comes with some basic amenities, such as showers and beds, but in general, are less than hospitable abodes. Oh, and to make conditions survivable, the air mix is only 2.5% oxygen, with the other 97.5% helium. This makes verbal communication difficult because the divers’ voices are constantly high pitched.
The work entails four-hour shifts, performing repairs, removing potentially corroded piping, etc., three divers at a time. Air, electricity, and oddly enough, water is funneled down to them at the job site. At the end of the shift, they spend another eight hours underwater resting before returning to the pressurized tank at the surface. Once “home,” other employees of the construction company provide them with food and clothes via an air lock. (The food, however, tends to taste bland in the pressurized environment.)
And unfortunately, the pipe is probably beyond repair. Instead, the DEP is building a bypass pipeline which will break ground in 2013 with completion estimated in 2019 — at the cost of roughly $2 billion.
From the Archives: The World’s Deepest Indoor Pool. Also incredibly deep, but no need for a month-long trip into a pressurized tank.
Related: As proof that there is a book on just about everything, Amazon has a title on “underwater repair technology.” But at $250 or so and over a decade old, well, it probably is not all that useful. (On the other hand, this device may pretty useful — if it could handle the seventy-story depths.)