1. GAUTAM BANERJEE UP Jal Nigam
RAIN WATER HARVESTING
GAUTAM BANERJEE
UP Jal Nigam

2. 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. 1

3. Reasons of Shotrage of Water Continued…..
Deforestation
(i) Less precipitation
(ii) Absence of Barriers
(a) Rain drops checked by leaves of tree
(b) Water slowly descends through twigs & trunk
© Humus – acts as reservoir
(d) Tiny creatures – helps percolation
1 hectare of forest-6-7 Lac ton of water
(after filtering) top layer can hold 1.2 Lac tons of water 2

4. 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 3

5. 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 4

6. What is rain water harvesting ?
It is the activity of direct collection of rain water
Rain water can be stored for direct use or can be recharged into the ground water aquifer 5

7. The roof catchment are selectively cleaner when compared to the ground level catchment
Losses from roof catchment are minimum
Built & Maintained by local communities
No Chemical contamination & only required filtration
Available at door step with least cost 16

8. The typical roof top rain water harvesting system comprises
Roof catchment
Gutters
Down pipe & first flushing pipe
Filter Unit
Storage Tank 17

9. 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 18

10. 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. 19

11. 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 20

12. 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 21

13. Filter Unit
The filter unit is a container or chamber filled with filter media such as coarse sand, charcoal, coconut fiber, pebbles & gravels to remove the debris & dirt from water that enters the tank. The filter unit is placed over the storage tank or separately. It may be of Ferro cement filter unit, Aluminum, Cement rings or Plastic bucket etc. 22

14. 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. 23

15. Size of Storage Tank Based on No. of person in the House hold
Per capita water requirement
No. of days for which water is required
Example
Drinking water requirement for a household with 5 family members, period 8 months & 6 lpcd
= 5x 180x 6
= 7200 Liters 24

16. Water available from Roof
Annual rainfall (in mm) x roof area (in sq. m) x co-efficient of run off for roof
co-efficient of run off
GI sheet
Asbestos
Tiled
Plaster on bricks/ Concrete 0.7
Water available from roof top 800mmx 20 sq.m=12800 Liters per annum 25

17. Water available from Roof continued……
Size of Tank =1.2 m dia 1.8 m height
No. of Tanks 4
Volume of Tanks 3.14x1.2x1.2x1.5/4
2.03 cum
2000 liters
Volume of of 4 tanks =
4x2000
8000 Liters
(this can be designed as per requirement) 26

18. Cost of Material for Tank
1. Cement 8 bags*Rs
2. Grit Cum
3. Sand .4 Cum
4. Perforated Cement rings 5 No
5. P/fabricated Cement rings 4 No
6. PVC pipe 63mm dia.*10M
7. P/fabricated Asbestos 10mm dia.*10mm
Gutters
8. Mason/ Labor charges
9. Transportation
Total 27

19. Cost of Material for Filtration Tank
1. P/fabricated cement rings 5*Rs
2. Cement bags*Rs
3. Sand 2 bags
4. Grit 4 bags
5. Charcoal 20 Kg*Rs
6. Sand for Plastering 4 bags
7. Mason/ Labor
8. White washing
9. Transportation
Total 28

20. Total Cost of construction Rs. 4400.00+ Rs. 1430.00= Rs. 5830.00
The cost on O/ M-
White washing
Water testing
(2 times a year) 29

21. Flooded with Fluoride-G/ water is not potable
Fluoride is an acute toxin with a rating slightly higher then lead. It is infect, one of the most bone-seeking elements known to human beings & groundwater in India shows the presence of unhealthy quantities of fluoride. A worrying scenario: daily ingestion of 2 milligram (mg) of fluoride could result in creeping Skeletal fluorosis after 40 years. Excess fluoride causes several diseases like Osteoporosis, Arthritis, Brittle bones, Cancer, Infertility in women, Brain damage, Alzheimer’s disease & Thyroid disorders 30

22. Flooded with Fluoride-G/ water is not potable
The very nature of fluoride increases this danger manifold. Almost half of each day’s fluoride intake is retained & is absorbed by the bones & teeth. It was Gerald Cox, of the Mellon Institute in the US, who first found in 1938 that while 1mg/ liter of fluorine in water prevents dental caries over 1.5mg/l causes mottled teeth. The bureau of Indian Standards (BIS) standard for fluoride content is 1-1.5mg/l. It is believed that levels above or below this could cause de4ntal decay. Ironically, there is an increased incidence of dental caries, yellow teeth & twisted limbs among people of all age groups in India. 31

23. 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. 32

24. Fluoride effected Villages
(based on RGNDWM 91)
Range No. of villages
1.5-2 ppm
2-2.5 ppm
2.5-3 ppm 97
3-4 ppm
4-8 ppm 33

25. Fluoride effected Villages continued……..
Range of Concentration ppm
Lower range of Concentration ppm
(about 67% villages)
Cause Salt concentration neat aquifers
Trend No. of villages increasing
Reason
(i) Heavy withdrawal of water from upper strata
(ii)Less charging of Strata due to Silt/ clayey upper layer of Soil 34

26. General distribution of Aquifers of Unnao35

27. How the problem can be minimized
By providing pipe water system with source (electric based)
(a) Surface water
(b) Deep tubewells
Recharging stratas through rainwater harvesting methods
(No. of villages of lower range concentration can be decreased)
Storing rain water for drinking purpose
(a) In areas where electricity problem is more
(b) In areas where concentration is more
© In areas where PWS is uneconomical
(d) In areas where dependable source is not available 36

28. Thank You 37