Water is one of the prime element responsible for life on earth.

97 % of the water on the earth is salt water only 2.5 of the total water on the earth is exists as fresh water.

Around 70 % of fresh water is frozen in glaciers and ice sheets.

Only 30 % of water is stored as ground water.

Around 0.3 % of the total fresh water exists in rivers, lakes, streams, ponds and springs are natural sources of water.

The water pollution are caused by increasing industrialization and human activities.

Mostly the water bodies get polluted by industrial, municipal and agricultural wastes.

Rains in India are largely due to the monsoons.

The monsoon of South Asia is among several geographically distributed global monsoons.

It affects the Indian subcontinent.

Most of the rain falls in a few months of the year i.e. from June to September.

Irrigation in India includes a network of major and minor

canals from Indian rivers, groundwater well based

systems, tanks, and other rainwater harvesting projects

for agricultural activities.

During ancient time irrigation system were managed by

local people.

The use of stored water was strictly regulated.

The optimum cropping patterns was based on the

availability of water and on the basis of decades/

centuries of experience.

The maintenance of these irrigation systems was a

local affair.

Irrigation in India

The arrival of the British changed the irrigation

systems.

The conception of large scale projects – large dams

and canals traversing large distances were first

conceived and implemented by the British.

Mega-projects led to the neglect of the local irrigation

methods.

After independence the government took over the

administration of these systems leading to the loss of

control over the local water sources by the local

people.

Storage of adequate

water for irrigation

Hydro power generation

Water for drinking and

industrial use

Flood control

Inland navigation

Recreation

Tehri Dam in Uttarakhand

Disadvantages

1. Social problems – Displacement of large number of

peasants and tribal without adequate compensation

or rehabilitation.

2. Economic problems - Swallow up huge amounts of

public money without the generation of proportionate

benefits.

3. Environmental problems - Deforestation and the loss

of biological diversity.

Disadvantages of Constructing Dams

The following issues to be settled during construction

of dams : -

Resettlement and Rehabilitation

Environment and forests

Sedimentary issues

Socio economic issues

Safety aspects

Issues for construction of dams

Water harvesting means capturing rain where it falls or collection of runoff for productive purposes.

It also takes measure to keep that water clean by not allowing polluting activities to take place in the catchment.

Watershed management emphasises scientific conservation of soil and water.

Objectives of watershed management

increases the production and income of the watershed community

mitigates droughts and floods

increases the life of the downstream dam and reservoirs

Age old water harvesting systems in India:-

Rajasthan - Khadins, tanks and nadis

Maharashtra - Bandharas and tals

Uttar Pradesh & M.P. - Bundhis

Bihar - Ahars and pynes

Himachal Pradesh - Kulhs

Kandi belt of Jammu region - Ponds

Tamil Nadu - Eris (tanks)

Kerala - Surangams

Karnataka - Kattas

Traditional water harvesting system —an ideal setting of the khadin system

The advantages of water stored in the ground are:

It does not evaporate, but spreads out to recharge

wells

It provides moisture for vegetation over a wide area.

It does not provide breeding grounds for mosquitoes

like stagnant water collected in ponds or artificial lakes.

The ground-water is relatively protected from

contamination by human and animal waste.

Why do we need to conserve water?

What are the ways to conserve water?

Make a poster for conservation of water.

Write a slogan on ‘water conservation’.