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RAIN WATER HARVESTING
Introduction
RWH is an outcome of awareness among
the people regarding the water scarcity.
Typical features of Rain Water Harvesting :-
Reutilization of waste water.
As RWH - neither energy-intensive nor
labour-intensive
It can be a cost-effective alternative to
other water-accruing methods.
With the water table falling rapidly, & concrete surfaces and landfill dumps taking the place of water bodies, RWH is the most reliable solution for augmenting groundwater level to attain self-sufficiency
OBJECTIVES
The main objectives of rain water harvesting are :-
Promote rain water harvestig by creating awareness among the people.
increasing the avaibility of ground water during periods of requirement.
preventing depletion of ground water reserviour in areas of over exploitation
Decreasing menace of flood on local and regional scale
reducing pressure on storm drains in urban areas
enhancing the quality of environment.
What is Rain Water Harvesting?
Rain water harvesting is simply collecting, storing and purifying the naturally soft and pure rainfall that falls upon your roof.
Rain water may be utilized for both potable and non- potabke requirements such as…
Drinking, cooking, bathing(potable water)
swimming pool
toilet flushing
Laundary
Landscape and Irrigation
Livestock and Animals
Necessity of Rain Water Harvesting
Water is one of the most important natural resource, it is the most basic need for all living beings as well as a very valuable national asset.
surface water source fail to meet the rising demands of water supply in ueban areas
water is being taken out from sub-surface water source on large scale, while on contamprary, input to it is not being matched up.
How To Harvest Rain Water?
The six basic components of a rain water harvesting system include:-
Catchment: Roof surface to collect rain.
Conveyance: Pipes from roof area to storagre.
Roof Washing: ‘First flush’ diverter to filter and remove contaminants.
Storage: Tanks where collected rain water is collected and stored.
Purification: Includes artificial filters, sand filters to remove suspended impurities
Distribution: System that delivers the rain water, usually including small pump and pressure tank.
Methods of rain water harvesting.
Roof Top Rain Water Harvesting System
Rooftop Rainwater Recharging
Following are the methods of recharging Ground Water Table:-
1. Well Recharging Method
2. Borewell Recharging Method:-
Other minor methods are:-
Farm Pit Method
Farm Trench Method
Costs and Economic Viability of Roof Water Harvesting System
Two types of systems:
Rooftop water harvesting
Rooftop rainwater recharging
Rooftop water harvesting costs:
Rs.50/m3 for 20-year life
Rs.25 for a 40-year life
RWHS won’t replace public systems in most physical and climatic conditions.
When Does RWHS Work?
Rain Water Harvesting– Advantages
1.Provides self-sufficiency to water supply
2.Reduces the cost for pumping of ground water
3.Provides high quality water, soft and low in minerals
4.Improves the quality of ground water through dilution when recharged
5.Reduces soil erosion & flooding in urban areas
6.The rooftop rain water harvesting is less expensive & easy to construct, operate and maintain
7. In desert, RWH only relief
8. In saline or coastal areas & Islands, rain water provides good quality water
CONCLUSION
Conservation of water.
since we cannot produce energy, but we can save it by preventing wastage.
In the same way we cannot produce water, but save it and protect our future