Rain Water Harvesting : An alternate Source of Water

Introduction The total amount of water on earth remains constant. The rapid growth in population together with the extension of irrigated agriculture and industrial development, are putting stress on the natural ecosystems. In the face of growing problems, society has begun to realize that it can no longer subscribe to a use and discard philosophy with any natural resource. One such resource is WATER. To deal with it, a technique called RAIN WATER HARVESTING was introduced where rain water is used to meet some of our daily needs.

What is Rainwater Harvesting Rainwater harvesting is the accumulating and storing, of rainwater. It has been used to provide drinking water, water for livestock, water for irrigation or to refill aquifers in a process called ground water recharge. The principle of collecting and using precipitation from a catchments surface. Rain water harvesting means to make optimum use of rain water at the place where it falls i.e. conserve it and not allow draining away and causing floods elsewhere.

Need of Rainwater Harvesting Water is becoming scarce. Surface water is inadequate to meet our demand. We have to depend on ground water. To reduce soil erosion. Groundwater is getting depleted and polluted. Improves the ground water quality. Increasing population of India. Of the total water on earth, only 3% constitutes freshwater. Rest is saline water in the oceans. 11% of the total fresh water on earth is groundwater available upto a depth of 800m which can be extracted for use

Rainwater Harvesting Techniques Roof top rainwater harvesting. Surface runoff harvesting .  

Roof Top Rain Water Harvesting In rooftop harvesting, the roof becomes the catchments, and the rainwater is collected from the roof of the house/building. It can either be stored in a tank or diverted to artificial recharge system. This method is less expensive and very effective and if implemented properly helps in augmenting the ground water level of the area.

How to Harvest Rainwater Collect water from the rooftop. Draw it down from pipes. Filter the water. Store in a sump or tank for later use. Charge the groundwater through a soak pit. Lead the water into a well to increase ground water content.

Elements of Rooftop Rainwater Harvesting CATCHMENT COUNDITS FILTERS STORAGE FACILITY

SURFACE RUNOFF HARVESTING Harvesting of surface runoff and storage of the same into reservoirs such as water pans makes it available for use when required. In this method of collecting rainwater for irrigation, water flowing along the ground during the rains will be collected to a tank below the surface of the ground.

TRADITIONAL RWH STRUCTURE BAWODI: Traditional step wells are called vavadi in Gujarat, or baoris or bavadis in Rajasthan and northern India. They were secular structures from which everyone could draw water. Most of them are defunct today.

Kunds or Kundis Covered underground tank, developed primarily for tackling drinking water problems. Usually constructed with local materials or cement, kunds were more prevalent in regions where groundwater is saline. Before the onset of rains every year, meticulous care was taken to clean up the catchment of the kunds. The proximity of a kund to the house or village saved time and effort in searching for drinking water.

Ooranis Designed to harvest and store rainwater to meet the drinking needs of a community. Created by excavating the soil which is then used to form bunds around the area. More than 39000 ooranis in Tamilnadu state alone

Paar System The rainwater flows from the agar (catchment area) and in the process percolates into the sandy soil. Kuis or beris are dug 5 to 12 m deep to access the water. Rainwater harvested through the paar technique is known as patali paani.

Advantages of RWH RWH is the ideal solution for all water requirements. Increase in ground water level. Reduces flooding of roads . Reduced soil erosion. Improves the ground water quality. Low cost and easy to maintain. Reduces water and electricity bills

Disadvantages of RWH Seasonal nature and uncertainty of rainwater supply depending on the region in the world. Capital costs . Regular maintenance and cleaning is essential for successful operation.

Summary On of the best way to solve the world burning facing issue: Water Scarcity. Helps in Raising Ground water level. Saving of energy per lifting of well and saving of Water bills. Harvested water can be used for Daily household needs. It is economical. Its not a permanent solution as water is not available throughout the year but it can be utilized to its maximum extent. Water is an important resource we should be very careful while dealing with it.

Rain Water Harvesting Noble Goal

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