Located south west of Jaipur, the Sambhar salt lake has a catchment area of 5,700- sqkms spreading into the districts of Nagaur, Jaipur, Ajmer in Rajasthan. It is said to be India’s largest salt water lake. The surface area of the lake used to be 230 sq km but the water has reduced to 7 km of ankle deep water, which also dries in the months of the summer. As only natural, the ground water for miles around is saline and unfit for drinking.

The lake has a history of salt production that goes back 1,500 years. There are 100 villages bordering the Sambhar Lake. Salt is the source of livelihood for all these people and several thousand more. It is also the chief source of ill health. Their skin becomes dessicated and their feet develop thick rashes. People working in the salt pans finally suffer psychological disorders. The average life expectancy for labourers of the salt pans is 45 years.

The traditional means of making salt was entirely dependent on the monsoon and the seasonal rivers that flowed through the land. Of late there has been the illegal use of borewells where water is pumped out from under the ground to react the with the soil, form brine and finally evaporate leaving behind salt crystals.

A consequence of this is that the few pockets of sweet ground water have been eroded because of the overexploitation of groundwater leaving the already water stressed population with almost no sources of sweet water. There are some village ponds, but these are few and far between and entirely dependent on recharge by rain. These dry up by the summer.

While the solution to a water crisis in any other water stressed region of India (or the world) would be rainwater harvesting and watershed development, the problem is compounded here because of the saline nature of the soil. So while both these initiatives are crucial, especially in the long term, what is also required, equally, is the immediate provision of sweet water. The ground water needs to be replenished, and then turned fit for human consumption. And so the idea of independent reverse osmosis (RO) plants for villages.

A reverse osmosis system needs a steady stable supply of electricity for it to run efficiently. As of today, the grid does not meet this requirement. What this proposal offers as a solution, is the opportunity to use a renewable energy source – to power the RO unit. Rajasthan has bright clear sunshine for at least 300 days of the year and solar energy becomes the natural choice.

With a view to provide the 4000 strong population of five villages a localized supply of clean safe drinking water and Improve the health of people living in these villages, Foundation for Rural Recovery & Development (FORRAD) in collaboration with MANTHAN has undertaken a ‘Drinking Water Project through Solar Powered Reverse Osmosis Technology’ in villages – Sinodiya, Jhag, Der ki Dani, in District Ajmer and Mordikala and Solawata in District Jaipur, Rajasthan. The fabrication of the RO units is being done by Centre Salt & Marine Chemicals Research Instutute.

The project was completed in Village – Sinodiya in December 2010 resulting in provision of sweet drinking water to 1540 villagers.

The meeting of Pani Samiti in progress.

The RO unit is driven by 5 KW solar power - generated through a total of 72 panels mounted on the roof of the RO building and the school

The 5 KW RO unit has an average capacity of producing 700 litres of water per hour and would be run over a period of ten hours. This will yield a daily output of 7000 litres of drinking water a day.

RO unit getting installed

Villagers gathering to collect Drinking Water.