What exactly is a Persian wheel? Also known as Rahat (in Urdu), it's a simple water lifting device, where a number of small pots are attached to a long chain. Two gear wheels make up the system and as the first one is revolved, the pots each dip and swallow water from the well and soon after pours itself out to a metallic shaft which in turns empties into an intricate network of troughs that distributes water adequately through the cropped area. It is believed that the technology originated in Egypt and as world shrunk through extensive trading, it spread to India and China.
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Advent of colonial rule in India was perhaps the first straw. As the British tried figuring out a procedure to exact taxes from all sections without stripping any one off completely, they obviously looked into issues of land revenue and agriculture. Decidedly unimpressed by "primitive"technologies such as the Persian wheel, this attitude was reflected in subsequent apathy towards such systems. It was the beginning of "Persian wheels"acquiring an antique/ historic value, rather than a local use one. It's difficult to pinpoint time frame when Persian Wheels migrated to South of India. Whether the source at all was from the North and not from trading routes down south or west needs to be looked into. Needless to say, rainfed areas in the South were quick on the uptake of such technologies. The district of Kolar stands out, as it has the highest number of wells and tanks in Karnataka. Historic records indicate that at one point of time around 60,000 water bodies existed in the district. Out of which 25,000 had Persian wheels attached to them . Needless to say, Persian wheels no longer dot the landscape of Kolar. The biggest drawback of Persian wheels was its inability to draw water when the level is low. Several factors have contributed to the disappearance of the Persian Wheel from Kolar town. A few still exist in the upper regions, primarily because of the height of water tables. However, even such systems are now under threat. Sustainability has been replaced with extractive paradigms, and the entry of bore wells has been the last straw. The Green Revolution, boosted by pump subsidies and unregulated ground water use, eliminated the Persian Wheels. The defunct wheels in Udaipur, Rajasthan, now exist as photo ops for foreign tourists, as deep in the semi - arid areas of Jodhpur, a much drier area as compared to Udaipur, bore wells dig deep and waters vegetables and opium. Kolar is now slowly experiencing the same winds of change. Around the Persian Wheels still in use, we found wells with installed electric pumps. The beginning of the domino effect, as the water level starts receding; one Persian Wheel after the other will fall into disuse and for survival all will have to enter the pump race. It's a pity, as Persian Wheels are anchored in source sustainability. A dug well is an excellent health indicator of water table in an area. Simply because one can see the water tables fluctuate, one can adjust cropping patterns accordingly. A Persian wheel in conjunction with well water that it is used to tap, is a holistic system. It prioritizes proper water management to maintain water tables which in turn would run the wheel. Any component malfunctioning, will throw the entire system out of gear. This is unlike a bore well, which never tells how much is available. Its invisibility facilitates rampant extraction, the negative aspects of which have already affected people's lives in various regions across the country. Granted, it provides freedom to farmers to grow cash crops and better their livelihoods, but its wealth based on damaging ecosystems and other marginalized sections in society. Keeping in mind climate change concerns, Persian Wheels is a clean water harvesting technology with zero GHG emission. But such esoteric debates rarely work on farmers who are pushed at all ends to adopt technologies that aim to maximize today's gain at tomorrow's loss. What would keep such systems ticking? S. Vishwanath and his Rainwater Club are looking into reviving and conserving such systems. It will be interesting to work out an incentives mechanism that allows local farmers to keep the Persian Wheel going. What can it be? Ecotourism? The scenic landscape of Kolar, which already has tourism attractions like rappelling and active indigenous theatre groups can attach the Persian wheels to an overall package with homestays and local cuisine thrown in. Wishful thinking? But then it was W.B Yeats who said that in dreams begin responsibilities. Perhaps it's a good place to start from. More photos : http://amitangshu.multiply.com/photos/album/35/Water_on_Wheels#