Water is life’s mater and matrix, mother and medium. There is no life without water.
 
                                                                                                                            - Albert von Szent-Gyorgyi  

Next to oxygen, water is most critical for human survival. It is the basic requirement for almost every activity on earth, be it, agriculture, industry,  domestic chore; from the time we wake up to the time we retire each day, there is just no escape from this vital dependence. 

 Water exists in the form of liquid (lakes, rivers, seas), solids (ice, glaciers) and gas (water vapours). Of all the fresh water in the world, only a small fraction is found in lakes and rivers. Most of it, approximately  98% exist in the earth in the form of soil moisture and ground water. Ground water thus forms the largest source of fresh water next to glaciers and icecaps. 

In India, over the past three decades, the burgeoning population and increased irrigation has led to excessive withdrawal of ground water without commensurate recharging. This in turn has resulted in a rapid fall in the water table in many parts of the country. Chronic water scarcity now looms over us like the proverbial sword of Damocles.  

 We have a piquant situation before us - although India receives around 4000 billion cubic meters water through annual precipitation,  only 75 billion cubic meters filters down to the ground and may be pumped back. A large portion of water is lost in the form of run-off and the rest just evaporates. The writing is already there on the wall before us, if the trend continues, we are in for a very grave water famine, but if we take timely action it is possible to have 1869 cubic meter per capita per year. As of now, while regional imbalances exist, there is no water scarcity per se, when you consider availability at the national level.  

The time is now ripe to initiate urgent measures to manage and augment ground water recharge, the best technique being Roof top and Run off rain water harvesting. In urban areas roof top rain water harvesting will immensely help in reducing demand on river and ground water system, which are now being overexploited and polluted. 

Why rain water harvesting: 

TO  meet the ever increasing demand for water
 -  reduce the choking of drains during heavy rain
 -  avoid flooding of roads
 -  augment the ground water storage and control decline of water level
 - reduce ground water pollution
 - improve the quality of ground water
 - reduce the soil erosion
 - supplement domestic water requirement during summer and drought 

CLEAN Jhansi techniques for water recharging through rain water harvesting: 

Rain water harvesting is a technique of collection or storage of rain water at a surface or in sub surface aquifer before it is lost in the form of surface run off. The augmented resource can be harvested in time of need. Artificial recharge to ground water is a process by which the ground water reservoir is augmented at a rate exceeding that under natural condition of replenishment. CLEAN Jhansi has taken an initiative for demonstration and replication of these  systems as follows: 

Utilization of wells: The underground water has steadily been going down the last three or four years, this has led to the drying up of many of the open and some of the shallow bore wells.  Instead of abandoning them, these wells can be utilized as recharge wells by connecting them to the water outlets from the rooftops. An example of this system is in place at Jai Academy School, Jhansi.  The cost effective process not only makes use of an existing well which acts as storage of precious rain water, but also restores the local under ground water availability. 

Decentralized percolation through pits: This is resorted to when the slope is not uniform. Here we dug several large, deep pits in the storm water passages. This can be seen at the Christ College where pits were dug to check the run off and roof top water. These pits were first filled with permeable material like pebbles, gravel and sand for purification and better percolation.

Earlier, the rain water from roof tops and the run off rain water from nearby areas used to pass through the school premises and flow into the big nala. The rain water is now collected more judiciously. The same system was demonstrated at the Dainik Jagran Press where a percolation pit was constructed in the storm water passage and this now receives and percolates the water. 

Recharge through bore well: In this technique  the rain water is recharged through bore wells ( be it functional or otherwise). The process involves the divergence of rain water from the roof top, runoff and from other paved areas into a defunct boring close to a functional boring.                                                

CLEAN Jhansi has demonstrated this  model at Aptech Call centre and Nirmal hospital, as a result, three defunct borings became functional during the first year of harvesting, the nearby hand pumps too got recharged.  

Through percolation pit:  Percolation pit is one of the easiest and most effective means of harvesting rain water. Pits of particular dimensions were filled with small pebbles or brick jelly and river sand and covered with perforated concrete slabs.  

Wherever the soil is deep, recharge through percolation pit with bore wells is a preferred method. In this system pits were dug and water from rooftop and other areas were first diverted to special drains and these drains were made to flow into  specific pits. This can be seen at Kendriya Vidyalaya No.3, Jhansi where four pits have been set up at four corners of the school – these receive the drain water and recharge the underground water.  

Advantages

There are obvious advantages to rain water-harvesting : 

• Provides self-sufficiency to your water supply
• Reduces the cost of pumping of ground water
• Provides high quality water, soft and low in minerals
• Improves the quality of ground water through dilution
• Reduces soil erosion in urban areas
• Roof top rain water harvesting systems are easy to construct, operate and maintain
• In hilly terrains, rain water harvesting is preferred
• In saline and coastal areas, rain water provides good quality water and when recharged to ground water it reduce the salinity and also helps in maintaining balance the fresh - saline water interface
• In Island, due to limited availability of fresh water aquifer, rain water harvesting is the most preferred source of water for domestic use
• In deserts, where rainfall is low, rain water harvesting has been providing great relief.

Amongst all natural resources available to us, water is the one critical factor over which we may be forced into a major conflict in the coming years. It is most ironical because this is one resource we have taken for granted, we have overused it and abused it, never giving a thought to conserving and preserving the vital commodity. It comes to us as manna from heaven, almost with clockwork regularity each year, let us learn to cherish and store it, before it is too late. q

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