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By
Steven Profaizer
“Water, water everywhere / Nor any a drop to drink.”
South Pole residents can relate to the famous lament of
this mariner, surrounded by undrinkable water.
The station sits on top of a two-mile-thick ice sheet,
which stretches to the horizon in every direction, gently
rolling like a calm sea. And while snow and ice blanket
the region, no drinking water exists in the polar desert.
Unlike the ancient mariner in Samuel Taylor Coleridge’s
poem, however, residents have the benefit of engineers
who have created the Rodriguez well to harvest enough
liquid water from the ice to meet their needs. But the
emphasis around station on water conservation and the
allotment of two two-minute showers a week serve as reminders
that the water that flows from the station’s taps
isn’t easy to come by.
“We create a Rod well, which is a cavity deep in
the ice where we melt ice to create our own drinking water,”
said Brad Coutu, South Pole facilities, engineering, maintenance
and construction manager.
This cavity is formed about 250 feet beneath the surface
by maintaining a pool of heated water throughout the well’s
lifespan. The bulb-shaped pocket gradually expands as
the walls continually melt away, creating a constantly
renewing source of water that Coutu said can produce up
to 1 million gallons.
A submersible pump and series of hoses cycle the water
up the ice shaft and through heat exchangers, while siphoning
a portion of the flow for the station’s use before
sending the rest back down to the well. Coutu estimated
that the system gives one gallon of water to the station
for every two gallons it reheats and returns to the well.
“The lifespan of a well is about seven years depending
on the amount of people down here and the water usage,”
Coutu said. “Once the well gets to be over 500 feet
deep, it takes too much energy to pull the water up and
recirculate it.”
The current well was created during the 2001-02 season
at a depth of 180 feet and currently rests 435 feet beneath
the surface, where it is now melting ice made of snow
that fell around 500 A.D, according to John Rand, who
provides engineering assistance focused on South Pole
issues. He said current projections look like it could
function for two more years.
As it takes about a year for a new Rod well to develop,
Coutu is already leading the effort to prepare the infrastructure
for the next Rod well.
“Before we use it, we have to wait until it has enough
water for us to take some out of it and still have enough
to recirculate for its continuous growth,” Coutu
said.
Rod wells have been used at the South Pole station since
1995. The first water well was installed by Cold Regions
Research and Engineering Laboratory engineers. The Rod
well system was developed by Army engineer Raul Rodriguez
at Camp Century in Greenland during the early 1960s.
Surface snow melting, which required a constant snow-gathering
effort, served as the Rod wells’ predecessor at the
South Pole.
“I’d say Rod wells are 80 percent more efficient,
especially when it comes to labor. A snow melter is very
labor intensive,” Coutu said. “Once the Rod
well is made, the hard work is done for the next several
years. Besides maintenance and preventative maintenance
operations, it’s essentially like your water supply
at home – you don’t even know it’s there.
You turn the faucet on and out comes water.”
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Antarctic
Sun
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