This document discusses water resources and rainwater harvesting. It notes that only 2.5% of water on Earth is fresh water, with much of it locked in ice sheets. India faces water scarcity and will face more by 2025. Major causes of scarcity are over-exploitation, large populations, agriculture, and pollution. Jawaharlal Nehru introduced multi-purpose river projects to generate power, support irrigation and more. These projects have limitations like environmental impacts. Traditional and modern rainwater harvesting techniques help conserve water and support agriculture, including rooftop collection, tanks, and surface runoff systems.

1. WATER
RESOURCES
Prepared by
Rose Mariya Mathai
Christ High School Nowshera

2. FACTS AND FIGURES
Un World Water Development- 2003
96.5% - OCEAN
2.5% - Fresh Water
70% fresh water under ice sheets
30% groundwater
India: 4% water per annum (rain and snow)
By 2025 face scarcity of water

3. WATER SCARCITY AND THE NEED FOR WATER
CONSERVATION AND MANAGEMENT
Water scarcity
Causes of water scarcity
 Water stress
 over-exploitation
 Large population
 Agriculture
 Industrialisation and Urbanisation
 Water pollution
 Rivers become toxic stream

4. MULTI-PURPOSE RIVER PROJECTS AND
INTEGRATED WATER RESOURCE
MANAGEMENT
Jawaharlal Nehru introduced
“The Temple of Modern India”

5. MULTI-PURPOSE PROJECTS
OBJECTIVES
 Generation of electric power
Soil conservation
 Flood control
 Irrigation
 Afforestation
 Fisheries
 Water navigation
 Tourism

6. MAJOR RIVER PROJECTS
RIVER PROJECT RIVER
Salal project Chenab
Bhakra Nangal Sutlej
Tehri Bhagiriati
Naraura Ganga
Rana Pratap Sagar Chambal
Gandhi Sagar Chambal
Kota Barrage Chambal
Sardar Sarovar Narmada
Pravara Godavari

7. MAJOR RIVER PROJECTS
RIVER PROJECT RIVER
Periyar Periyar
Hirakud Mahanadi
Tilaya Damodar
Damodar Valley Project Damodar
Koyna Krishna
Nagarjuna Sagar Krishna
Tungabhadra Tungabhadra
Mettur Kaveri
Krishna Raj Sagar Kaveri

8. MULTI-PURPOSE PROJECTS
LIMITATIONS
 Environmental Impact
Effect on soil fertility
Impact on society
Impact on Aquatic Life
Change in cropping pattern
Territorial water dispute
Excessive sedimentation at the Bottom of the
Reservoir

9. MULTI-PURPOSE PROJECTS
Movements against
 Sardar Sarovar Dam Project
 Tehri Dam
Rihand valley
 Sabarmati basin
 Kaveri River disputes

10. M
J
O
R
P
R
O
J
E
C
T
S

11. RAINWATER HARVESTING
Rainwater harvesting is a type of harvest
in which the rain drops are collected and
stored for the future use, rather than
allowing them to run off.

12. RAINWATER HARVESTING
Traditional Methods
 Khadins and Johads
Bamboo drip irrigation system
Guls or Kuls
Inundation channels
Tanks

13. RAINWATER HARVESTING
Khadins and Johads
Harayana and Rajasthan

14. RAINWATER HARVESTING
Bamboo drip irrigation system
Meghalaya

15. RAINWATER HARVESTING
Guls or Kuls
Himalayas

16. RAINWATER HARVESTING
Inundation channels
Bengal

17. RAINWATER HARVESTING
Tanks
Rajastan

18. RAINWATER HARVESTING
Modern Methods
 surface runoff harvesting
Rooftop Rainwater Harvesting

19. RAINWATER HARVESTING
surface runoff harvesting
method of collecting rainwater flowing
along the ground during the rains will be
collected to a tank below the surface of
the ground for irrigation and other
purposes.

20. RAINWATER HARVESTING
surface runoff harvesting

21. SURFACE RUNOFF HARVESTING

22. RAINWATER HARVESTING
Rooftop Rainwater Harvesting
It is a system of catching rainwater where
it falls. In rooftop harvesting, the roof
becomes the catchment, and the
rainwater is collected from the roof of the
house/building.

23. RAINWATER HARVESTING
Rooftop Rainwater Harvesting
It can either be stored in a tank or
diverted to an artificial recharge system.
 This method is less expensive and very
useful and, if implemented correctly.
It helps in augmenting the groundwater
level of the area.

24. ROOFTOP RAINWATER HARVESTING

25. ROOFTOP RAINWATER HARVESTING
Components of the Rooftop Rainwater
Harvesting
1. Catchments
2. Coarse mesh
3. Gutters
4. Conduits
5. First flush
6. Filters
7. Storage tanks

26. ROOFTOP RAINWATER HARVESTING
1.Catchments
The surface which directly receives the rainfall and
provides water to the system is called catchment
area.
Terrace of a building
Courtyard of a building

27. ROOFTOP RAINWATER HARVESTING
2. Coarse mesh
It prevents the passage of debris, provided in the roof.

28. ROOFTOP RAINWATER HARVESTING
3. Gutters
 Channels which surrounds edge of a sloping roof to
collect and transport rainwater.
 Gutters can be semi – circular or rectangular and
mostly made locally from plain galvanized iron sheet.
 Gutters need to be supported so they do not sag or
fall off when loaded with water.

29. ROOFTOP RAINWATER HARVESTING
4. Conduits
 Conduits are pipelines or drains that carry rainwater
from the catchment or roof top area to the
harvesting system.
 Commonly available conduits are made up of
material like polyvinyl chloride (PVC) or galvanized
iron (GI).

30. ROOFTOP RAINWATER HARVESTING
5. First flush
 A first flush device is a valve which ensures flushing
out of first spell of rain away from the storage tank
that carries a relatively larger amount of pollutants
from the air and catchment surface.

31. ROOFTOP RAINWATER HARVESTING
6. Filters
 The filter is used to remove suspended pollutants
from rainwater collected from roof top water. Basic
function is purify water.
1. Charcoal water filter
2. Sand Gravel Filter

32. ROOFTOP RAINWATER HARVESTING
1. Charcoal water filter
Charcoal filters can be made in-situ or in a drum. Pebbles, gravel, sand, and
charcoal as shown in the figure should fill the drum or chamber. Each layer
should be separated by wire mesh. The thin layer of charcoal is used to
absorb odor if any.
2. Sand Gravel Filter
These are commonly used filters, constructed by brick masonry and filleted by
pebbles, gravel, and sand. Each layer should be separated by wire mesh.

33. ROOFTOP RAINWATER HARVESTING
7. Storage tanks
Purified water stored in tanks

34. METHODS OF ROOFTOP RAINWATER
HARVESTING
1. Storage of Direct Use
2. Recharging Groundwater Aquifers
3. Recharging other water bodies

36. RAINWATER HARVESTING
ADVANTAGES
 It is considered as the purest form of natural
water and a major source of drinking water.
This water can be used for agricultural
purposes.
The water stored under the ground in tanks
help in cooling basement rooms in the hot
summer.
It helps in meets our growing
water needs

38. WORLD
ENVIRONMENTAL
DAY