Ice Stupa - a form of artificial glacier

LADAKH IS a trans-Himalayan mountain desert in the extreme north of India with villages located at 2,700m to 4,000m altitudes. It is a cold desert with winter temperatures touching -30° C, and an average annual rain/snow fall of only 100 mm. Human settlements are almost always located around glacial streams which feed into the Indus and other rivers as tributaries. The key to human settlement in this cold desert is the art of diverting water from the streams through meticulously built canals toward deserts to grow crops like barley, wheat, vegetables and trees like apricots, apples, willow and poplar.

THE PROBLEM

Most villages face acute water shortage, particularly during the two crucial months of AprilMay when there is little water in the streams and all the villagers compete to water their newly- planted crops. By mid-June there is an excess of water and even flash flooding due to the fast melting of the snow and glaciers in the mountains. By mid-September all farming activities end, and yet a smaller stream flows throughout the winter steadily but wastefully going into the Indus river without being of use to anybody.

The problem is getting worse with time as Himalayan glaciers are disappearing due to global warming and local pollution.

SOLUTION

After two years of experiments at SECMOL Alternative Institute, the Pheyang Monastery near the institute started making ice stupa from artificial glaciers which store this wasting winter water in the form of ice mountains that melt and feed the farms when water is most needed by the farmers.

The idea behind artificial glaciers is to freeze and hold the water that keeps flowing and wasting away down the streams and into the rivers throughout the winter. Instead, this ice will melt in the springtime, just when the fields need watering. The concept of artificial glaciers is not new to Ladakh. Ancestors used to have a process of ‘grafting glaciers’ in the very high reaches of mountains.

However, since these are based on horizontal ice formation, they need very high-altitude locations (above 4,000m), constant maintenance and a north-facing valley to shade the ice from the spring sun. Because of these problems, a new approach in which the glaciers would be free of location, frequent maintenance and shading requirements had to be undertaken.

In the new model, this is achieved by freezing the stream water vertically in the form of huge ice towers or cones of 30 to 50m height that look very similar to the local sacred mud structures called Stupa or Chorten. These ice mountains can be built right next to the village itself where the water is needed. Very little effort or investment would be needed except for laying one underground pipeline from a higher point on the stream to the outskirts of the village. Normally the head difference is easily 100m over a distance of roughly one to three kilometres.

HOW IT WORKS

The idea is very simple and needs no pumps or power. Water maintains its level, therefore water piped from 60m upstream would easily rise close to 60m up from ground when it reaches the village. For simplicity, imagine that the pipe is mounted on a mobile- phone tower of that height, and then it is made to fall from that height in cold Ladakhi winter nights when it is -30 to -50°C outside (with wind chill factor). The water would freeze by the time it reaches the ground and slowly form a huge cone or Ice Stupa roughly 30 to 50m high. In reality a tower structure is even needed as the piped water can first freeze at ground level and then mount higher, metre by metre, as the thickness of the ice grows, finally reaching close to the height of the source.

The idea is also to conserve this tower of ice as long into the summer as possible so that as it melts, it feeds the fields until the real glacial melt waters start flowing in June. Since these ice cones extend vertically upwards towards the sun, they receive fewer of the sun’s rays per the volume of water stored; hence, they will take much longer to melt compared to an artificial glacier of the same volume formed horizontally on a flat surface.

THE PROTOTYPE

In order to test these ideas, the SECMOL Alternative Institute built a prototype. It chose a spot that was fully exposed to sunlight and located at the lowest altitude (hence warmest) possible in the whole of Leh Valley. This was done to prove that if it works in these conditions, then it can work anywhere in Ladakh. It took one month to build an Ice Stupa approximately 7m high, fed by the campus supply pipe which has its headwork roughly 15m above the spot. The Institute would consider the experiment a success if the Ice Stupa lasted until the 1st of May to melt and the project participants were delighted when, on May 1st, the Ice Stupa was still 3m high and still providing water to the earth around it. The entire Stupa did finally finish melting on the 18th of May, thus proving that bigger masses at much higher altitudes could last well into mid-summer.

DETAILS, ICESTUPA.ORG