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WaterSurface water is quite scarce in this semi arid region and is available only for a limited time of the year from the local reservoir, a small lake which is filled during raining season through a widely branched system of rivers and checkdams. During the dry season the rivers dry up and the water from the reservoir is being pumped to the fields for irrigation. Its capacity usually lasts for 2 - 3 months and allows the farmer to bring his crop to maturity. As a relatively new practice, some farmers have started to plant a second crop directly into the humid soil in the bed of the lake after all water is being pumped out. This fertile soil is washed from the fields into the rivers during heavy rainfalls and settles in the reservoir. Although following this practice might present an opportunity for some farmers to grow an additional crop, it is basically an inappropriate use of the water storage system: In the first place, the soil along the waterline should be secured by planting trees and shrubs, so it does not get washed into the river, secondly the soil being flushed into the lake should be removed during the dry season. But due to the present practice, the reservoir never gets cleared and is ever more getting filled up with silt. The layer of residing sediments has already reached several meters, thus reducing the overall capacity of the water reservoir to a great extent and so shortening each irrigation period.  After the water supply from the reservoir is consumed, ground-
water from wells and boreholes has to be used for additional or late crops, thus creating stress on the groundwater table. With a selfsufficient agriculture, the groundwater consumption during the dry season was usually compensated by rains during the subsequent monsoon. But this balance is no longer sustained, as the newly introduced cash crops and additional crop cycles place an increased demand for irrigation with groundwater. As a consequence, additional boreholes, far deeper than the traditional wells and equipped with high performance submersible pumps, are being installed in order to meet the need for irrigation water - further augmenting stress on groundwater tables. An additional impact on the water economy is caused by the recent climatic changes with sometimes severely reduced rainfalls in monsoon. Subsequently the groundwater tables do not restore naturally and are getting depleted, which poses whole regions at risk of drying up and turning into wasteland. Here is a short movie showing irrigation practice and the lake after it is emptied There have massive amounts of money and effort been invested into the Narmada Project, where a big canal has been built in order to provide the highly developed agricultural regions in the north of Gujarat with a sufficient supply of water. However, this supply is restricted to a relatively small area and to date it is unavailable to regions further south towards the coastal areas, where depleted or saline groundwater is becoming a serious problem for the farming community.  For restoring groundwater resources some relatively simple methods have shown very successful in other locations and can be applied here as well. These are: 1. Plantation of trees to foster water retention of soil and to prevent soil erosion. Especially planting trees and shrubs with dense roots along the waterways will help to prevent soil from being flushed into lakes.
2. Clearing congested water reservoirs, increasing their depth/size or building additional ones. Especially building deeper reservoirs with smaller water surfaces can help to prevent high evaporation rates in a hot climate.
3. Building checkdams to harvest rainwater that will otherwise drain away as method to get these lakes filled during monsoon, thus having additional water available for irrigation purposes during the dry season.
4. Recharging the wells during raining season by channeling rainwater into the wells. This water has shown to push back into the water ducting layers by gravity, following the laws of physics establishing an even level.  As common practice the fields are subdivided into segments which are flooded once a day for irrigation. This takes a lot of water and much of it will evaporate without being of much use to the plant. In order to preserve groundwater tables it would be advisable to reduce water consumption for irrigation, which could be accomplished by the use of drip irrigation and sprinkler systems. Drip irrigation systems feed a continuos supply of water directly to the root of the plant and are applicable where the plants are grown in rows. Where the plants are unevenly distributed, sprinklers could do the job, with short running intervals several times per day. Both Systems need a certain constant water pressure to function properly. The disadvantage of these systems is their high initial cost. There are currently imported drip irrigation systems available, but their price exceeds the budget of a small farmer. However, these systems are quite sophisticated and a cheaper and simpler solution made up from locally available parts could possibly do the job. This issue deserves some further investigation.Drinking waterSurface water, if and where available, is hardly suited for drinking purpose without proper treatment. Untreated water is a killer. Every year, 1.8 million children die of diseases caused by poor sanitation and dirty water in developing countries, the United Nations states. Climate change is expected to aggravate the drinking water situation in water-stressed areas. Water for human and animal consumption is preferably drawn from open wells or boreholes. In our case, there are several water ducting layers at different depths with varying water quality and not all water from boreholes is palatable, as some of it is loaded with mineral salts and tastes brackish. To drill a well requires some investment and there is no guarantee for a successful drilling or for a good water quality. This short movie gives you an idea what it takes to install a boring. What is shown here in a few minutes took many hours to get accomplished. The depth of this particular borehole is 70 Meters (220 ft). Drinking water should preferably be derived from borings outside of the village, as there is a lesser risk of contamination by waste that can get washed into a borehole during heavy rains, However landownership and the cost for drilling and piping have to be taken into consideration. 
As the risk of water contamination increases with density of population and intensified agricultural practice, it is advisable to purify water before consumption. This can be done by exposing it to solar UV radiation e.g. by storing it in transparent (PET) containers, or by boiling it. Although these methods do eradicate microbial contamination, they do not remove particle matter or chemical residues. For this it would have to be filtered, e.g. through activated charcoal, a process which is not easily available. The purification process does not necessarily need to be centralized. In fact it is advisable to have it done at the point of use, especially as some houses afford their own borehole. The cleaning process should be low tech, easy to use and affordable for the villager to apply it. A convenient and cheap method to get clean drinking water is a simple solar device that can be used anywhere and that purifies water by an evaporation/condensation process. The exposure to sunlight grants for eradication of germs and the evaporation leaves back all biological contaminants and most of other impurities. (Please note: volatile organic components, such as pestizide and herbizide residues etc., in the source water can hardly be eliminated, as they often evaporate and condense together with the water, hence they will remain in the condensate. It is therefore important to use only water from sources free of such pollutants!). top
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