Kluane home to underground treasure
Every day people in Haines Junction benefit from the area's spectacular natural assets; its mountains and glaciers, lakes and rivers. By next winter another of the region's major resources could be helping to heat some of the town's buildings, and this one lay undiscovered and out of sight only two short years ago.
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The Town of Haines Junction discovered a huge warm water aquifer while drilling a new well for drinking water.
(photo: Gartner Lee Ltd.)
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Back then Haines Junction had water problems. One of the town's two wells had dried up, and no one knew how long the remaining one would last. In the fall of 2002, the village took the plunge and began drilling a deep well, hoping to tap into a new aquifer.
They got more than they ever bargained for. After drilling down about 350 metres, they found liquid treasure; a warm water aquifer so large that it could eventually heat many of the community's buildings as well as supply drinking water.
The water -- which stays at about 17 degrees Celsius -- is artesian and always under pressure so it does not even need to be pumped to the surface.
"We were just looking for an alternate water supply that could produce 50 gallons a minute," says John Farynowski, the mayor of Haines Junction. "Instead we're getting 200 gallons a minute without even having to pump it out of the ground."
"Warm water artesian aquifers are very, very unusual," confirms Don Flinn, the managing director of the Energy Solutions Centre. The Centre has formed a partnership with the community of Haines Junction to investigate ways that the aquifer could be used to heat some of the town's buildings.
Sometime this summer the village councillors expect to consider different options provided by a consultant on how the heat could be used. A heat pump has already been installed in the town's pump house, and Farynowski estimates that this small project already saves $300 to $400 per month.
Interestingly enough, one of the main technical challenges for using this heat source is disposing of the leftover water. The town only uses about 100 gallons per minute for drinking water. "There is not a lot of heating potential in that amount of water," says Farynowski. "We could maybe heat the school and the main town convention centre."
After the water is used for heating the buildings, it would be sent back to the town's main water tower, and the cooler water would be distributed for drinking.
If the town decides to pump more water for heating, they then have to figure out what to do with the leftover water after the heat has been extracted from it.
Drilling a second well so that the leftover water could be pumped back into the aquifer would be very expensive. And forcing leftover water back into the aquifer is also a challenge. "Right now the pressure in the aquifer pushes the water 1.8 kilometres in distance and then right up into the water tower without a pump," says Farynowski.
The nearby Dezdeash River might seem like the obvious place to discharge any excess water, but it is not a good match. The aquifer water is cleaner than the river water because it is what is known as "juvenile" water. Geologically young in age, it has not spent enough time in the ground to pick up many minerals.
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The aquifer produces 200 gallons of water per minute at a temperature of 17° C.
(photo: Gartner Lee Ltd.)
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"You have to be very careful with what you do with this water," says Flinn. "This water is so clean that people are interested in selling it."
Tapping the aquifer cost almost half a million dollars -- about twice what the village had expected to spend -- because special equipment had to be brought in to handle the artesian flow.
But Farynowski says the warm water is already saving money for the village. The main water lines usually freeze even during mild winters and have to be dug up and repaired, but this year they have flowed freely.
"Lots of lines in houses used to freeze as well, but that has not happened even though it has been a bit colder this year," he says.
He cites the environmental savings as another major bonus of the geothermal heat. "We won't be polluting the atmosphere and using fossil fuels. People like that option. And we will have a stable heating supply."
Geologists assume that water in the aquifer first falls as rain or snow high in the Auriol Range. After spring melt, the water runs down into the valleys and seeps through the sand and gravels which fill the valley bottoms, pooling up as it hits impermeable layers left behind by glaciers and ancient lakes.
At that point, the unique geology of the Kluane area comes into play. Haines Junction is only 100 kilometres away from the Fairweather Fault, which forms the boundary between two major tectonic plates. As the Pacific and North American plates grind against one another, they generate both earthquakes and lots of heat.
Geologists who surveyed the area conclude that the groundwater is coming into contact with either high temperature rock or thermal fluids. "The heat in the deeper aquifer must be a result of seismic activity in the area," says Flinn.
While it is not artesian, a warm water aquifer underneath the Riverdale subdivision in Whitehorse already warms the city's water supply in winter and heats the Whitehorse Rapids Fish Hatchery.
Mayo also has warm water underground which it hopes to use in the future. The community tried unsuccessfully to use heat exchangers in its deep well back in the 1980s when the technology was not as efficient.
Because of the Yukon's high level of seismic activity and complicated geology, chances are good that other communities here could also be sitting on top of warm water aquifers. The Energy Solutions Centre and the territorial government are now looking for this buried treasure by analyzing well logs from Yukon communities.
For more information on these projects, contact the Energy Solutions Centre at 393-7062.
