Lifting and Extraction

The paper by International Water Management Institute (IWMI), Challenge Programme for Water and Food (CPWF) and University of Arizona deals with energy supply and expansion of groundwater irrigation in the Indus-Ganges basin. Irrigation using groundwater has expanded rapidly in South Asia since the inception of the Green Revolution in the 1970s and it represents the largest source of irrigation in the basin.

This CGWB map provides us with block level information about groundwater exploitation across the country. Blocks are categorized as safe, semi-critical, critical, over exploited and saline based on the usage.

As ground water levels decline in India, Persian Wheels cannot reach the water to draw them out from open wells. One such Persian wheel stands forlorn and frustrated as the water table has dipped in Kolar, Karnataka India. This wheel has worked for the last 80 years and 2007 was the first time that the water table fell and the wheel could not work for the day.

Most drinking water projects are designed for supply of treated water through pipes to communities ; this requires investment on infrastructure such as pumps, overhead tanks, supply pipes, water purification equipment and after the project, maintenance staff and funds; while all this calls for planning, funding and time to execute, yet we cannot be certain that the water delivered remains uncon

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.

Two instances of foot-powered water pumps that we have come across. Have readers come across others and do they feel that these are a useful invention?

Read about Treadle Pump Programme http://www.ide-india.org/ide/treadlepump.shtml