22-12-2012, 12:27 PM
RAIN WATER HARVESTING
RAIN WATER.ppt (Size: 112.5 KB / Downloads: 523)
Reasons of Shortage of Water
Population increase
Industrialization
Urbanization
(a) Increase in per capita utilization
(b) Less peculation area
In places where rain fed/ irrigation based crops are cultivated through ground water
Decrease in surface area of Lakes, talab, tanks etc.
What is the solution ?
Rain water is the ultimate source of fresh water
Potential of rain to meet water demand is tremendous
Rain water harvesting helps to overcome water scarcity
To conserve ground water the aquifers must be recharged with rain water
Rain water harvesting is the ultimate answer
Why Rain water be harvested
To conserve & augment the storage of ground water
To reduce water table depletion
To improve the quality of ground water
To arrest sea water intrusion in coastal areas
To avoid flood & water stagnation in urban areas
Roof catchment
The roof of the house is used as the catchment for collecting rain water. The style construction and material of the roof effect its suitability as a catchment, Roofs made of corrugated iron sheet , asbestos sheet, Tiles or Concrete can be utilized for harvesting the rain water
Gutters
Gutters are channels fixed to the edges of roof all around to collect & transport the rainwater from the roof. Gutters can be made in semi-circular and rectangular shape with cement pipe, plain galvanized iron sheet, PVC pipes, bamboos etc. Use of locally available material reduce the overall cost of the system.
Down Pipe
It is the pipe which carries the rainwater from the gutters to the filter & storage tank. Down pipe is joined with the gutters at one end & the other end is connected to the filter unit of the storage tank. PVC or GI pipe of 50mm to 75mm (2 to”) are commonly used for down pipe. Bamboo can be also used wherever available and possible
First Flush Pipe
Debris, dust & dirt collect on the roof during non rainy periods when the first rain arrive. A first flush system arrangement is made to avoid the entering unwanted material into the Filter media & storage tank. This is a simple manually operated arrangement or semi-automatic system with a valve below the ‘T’ junction
Storage Tank
It is used to store the water that is collected from the roof through filter. For small scale water storage plastic buckets, jerry cans, clay or cement jars, ceramic jars, drums may be used. For larger quantities of water, the system will require a bigger tank with cylindrical or rectangular or square in shape constructed with Ferro cement or cement rings or plain cement concrete or reinforced cement concrete or brick or stone etc. The storage tank is provided with a cover on the top to avoid the contamination of water from external sources. The storage tank is provided with pipe fixtures at appropriate places to draw the water to clean the tank & to dispose of extra water. A provision for keeping the vessel to collect the water is to be made.
Flooded with Fluoride-G/ water is not potable
A recent publication of the Geographical Survey of India (GSI) names areas that should go on fluoride red alert: Fazilka & Jalalabad in the border district of Ferozpur in Punjab, parts of Gurgaon, Rewari, Mahendranath, Hisar, Fatehabad & Faridabad district in Haryana, Unnao, Rae Barely & Sonebhadra district in Uttar Pradesh, Sidhi district in Madhya Pradesh, Beed district in Maharastra, Nalgonda district in Andhra Pradesh and Dindigul district in Tamilnadu.