Water conservation is the most important step in the direction of finding solutions to all issues concerning the conservation of the environment and ecology. Each one of us is responsible for conservation. There is a need to change one’s attitudes and habits. The water supply for irrigation and other purposes can be done by various other low cost and high reward schemes. The alternatives focus on the use of water for irrigation and other agriculture, landscaping, drinking water and other municipal uses. Water harvesting is one such simple and important step that can effectively contribute to water conservation.
The growing human population and rising standards of living in the modern world, raise an eminent shortage of the supplies of fresh water. In India, except for a small part of the nation, almost the entire rainfall occurs during three to four monsoon months. Rain water harvesting is an effective way to store and use rain water. Water harvesting means the collection, storage and efficient utilisation of rain water and runoff water. The rain water flowing over land or through streams, gullies, creeks etc. spring protection, tapping subsurface shallow seepage or ground water flow below the stream bed through shallow wells should be stored. Roof rain water harvesting is being given special importance in both rural and urban areas and particularly in areas where water quality problems exist. The rain water that falls on the rooftops can be harvested for groundwater recharge using appropriate techniques. This method may be applied for the roofs of existing houses or buildings as well as those under construction.
The state authority significantly contributed to rain water harvesting projects in various areas including the national capital region. The officials announced surprising results of increase in water levels in many parts of the city. The results prove that rainwater harvesting has improved the water quality. The estimate of the Delhi Jal Board suggests that a total of two million cubic metres of water can be utilised for groundwater recharge at a cost of about 189 million rupees.
There is an example of the huge cost differences between the top-down establishment approaches to water management and community-led approaches that comes from Alwar district in the state of Rajasthan. The water harvesting structure of this region is locally known as Johad that is a prime example of an inexpensive and simple traditional technology that is effective in terms of recharging the ground water of the entire region. These structures are simple mud and concave shaped barriers built across the slopes to arrest the rainwater run-off with a high embankment on three sides while the fourth side is left open for the water to enter.
Tarun Bharat Sangh has helped villagers to build and to restore thousands of water harvesting structures based on mainly earthen embankments or small concrete dams across seasonally flooded gullies for more than a decade. These structures impound water that soaks into the ground in order to recharge groundwater. Then the water is drawn from wells. The water collected during monsoon penetrates into the sub-soil. This recharges the ground water and improves the soil moisture in vast areas, mostly down-stream. The ground water can be drawn from traditional open wells, built and maintained by the villagers themselves without any input from outside.
Tarun Bharat Sangh is a non-government organisation, headed by Ramon Magsaysay Award recipient Rajendra Singh. According to calculations, around 700,000 people benefited from improved access to water for household use, farm animals and crops in a couple of decades. The organisation has contributed around Rs. 70 million to the cost of the water harvesting structures. This works out to a cost of Rs. 500 per hectare irrigated and Rs. 100 per person supplied with drinking water. By comparison, supplying one person with water from the notorious Sardar Sarovar Dam on Narmada River will cost Rs. 10,000, and supplying one hectare with irrigation water from the mega project will cost Rs. 170,000 which is 340 times more than the cost in Alwar.