RAIN WATER HARVESTING
             
       

 

Introduction

Water is one of the most commonly used substances on earth. Water is required for all our day-to-day activities and as explained earlier, water supply in urban areas is always short against the total demand. As a result, extraction of ground water has tremendously increased over the years and has led to depletion. Moreover, due to rapid urbanisation, infiltration of rainwater into the subsoil has decreased drastically and recharging of ground water has diminished. Therefore, the present scenario requires an alternate source to bridge the gap between demand and supply. Rainwater, which is easily available and being the purest form of water, would serve as an immediate source to augment the existing water supply.


Rain Water Harvesting is the principle of collecting and using precipitation or rain from a catchment surface. RWH can also be defined as the process of collecting and storing rainwater in a scientific and controlled manner for future use.


Rain Water Harvesting (RWH) is an old technology gaining popularity in a new way, like old wine in new bottle. RWH is enjoying a renaissance of sorts in the world, but it traces its history to biblical times. Extensive rain water harvesting apparatus existed 4000 years ago in Palestine and in Greece. In ancient Rome, residences were built with individual cisterns and paved courtyards to capture rainwater to augment water from city's aqueducts. As early as the third millennium BC, farming communities in Baluchistan impounded rainwater and used it for irrigation and dams built of stone rubble were found in Baluchistan and Kutch in Gujarat in India.


RWH is gaining importance and is becoming essential to implement because:-

  1. Surface water is inadequate to meet our demand and we have to depend on ground water

  2. Due to rapid urbanization, infiltration of rain water into the sub-soil has decreased drastically and recharging of ground water has diminished

  3. Over - exploitation of ground water resource has resulted in decline in water levels in most part of the country

  4. To enhance availability of ground water at specific place and time

  5. To arrest sea water ingress

  6. To improve the water quality in aquifers

  7. To improve the vegetation cover

  8. To raise the water levels in wells & borewells that are fast drying up

  9. To reduce power consumption

  
 
" Water water every where, not a drop to drink"                                                                "Rain water is a gift from nature. Catch it when and where it falls"