Water is another prime natural resources after land resources. It is life in itself. Besides various uses of water, it is importantly used in irrigation as India is an agricultural country. Use of water in irrigation gives an impetus to extend our cultivable area and also productivity of agriculture in the country.
Rainfall in India
India is said to be Monsoon country because the climate in India is Monsoon climate. But the distribution of Monsoon rainfall is uneven both regionally and seasonally. Moreover, it is undependable as its occurrence is not at stipulated times.
Unevenness
Unevenness of Monsoonal rainfall in India is found both regionally and seasonally:
Regional Unevenness : Regional unevenness in Indian rainfall is described in the following terms:
- Mysinram receives the heaviest rainfall in the world. Here the annual rainfall exceeds 1080 cm. On the contrary there are also places in India which receive the least rainfall. Barmer in Thar Desert receives only less than 12 cm annual rainfall. Sometimes it also happens that the western-most part of Rajasthan Desert does not experience even a single centimetre of rainfall for years together.
- In the Great Plains of the North (the Ganga-Yamuna Plain) Monsoonal rainfall goes on decreasing from east to west during the period of South-West Monsoon. Rainfall on Assam hills exceeds 250 cm while Bihar plain receives only 125 to 150 cm rainfall. In Punjab it decrease to 75 cm only.
- In the Peninsular India Monsoonal rainfall decreases from west to east. Western slopes of the Western Ghats enjoy more than 250 cm of Monsoonal rainfall. Rainfall decreases from 75 to 100 cm on the eastern slopes of the Western Ghats. It further comes down in the Maidan region of Karnataka, thus putting it in the rainshadow area of the South-west Monsoon. Here rainfall is only 40 to 60 cm.
During winter also, regional variations are found in rainfall distribution; North-west India obtains upto 25 cm of winter rainfall while on the coasts of Tamilnadu as much as 75 cm winter rainfall occurs. In other parts of country winter rainfall is negligible.
Seasonal Unevenness : Seasonal unevenness is very glaringly experienced in the Monsoonal rainfall of India. This unevenness is revealed in the following account.
- During summer and rainy season India receives 75% to 85% of the total annual rainfalls while only 15 to 25% of the total annual rainfall is obtained in the remaining period of the year. South-west Monsoon provides rains in summer and rainy season while North-east Monsoon and western disturbances cause winter rainfall.
- Tropical cyclones bring rainfall on the coastal region in summer and in the season of Retreating Monsoon.
Undependability
- Normal time of the burst of break of Monsoon in India is 1st June and by first July every nook and corner of the country should be under its influence. But this does not happen always. Sometimes it breaks very early sometimes it is very late. Likewise, sometimes it breaks very late and also ends very early.
- Sometimes we receives more than average rainfall while in another years rainfall is very scanty. In the year of excess rainfall floods occur, causing incalculable loss to life and property. When rainfall is scanty, famine conditions prevail. People and live-stock begin to starve for want of food, and water.
Sources of water resources
Water resources include surface water, ground water resources mainly. The source of both the water resources whether surface water resources or ground water resources—all are available through rains.
Surface water resources include:
- Water in the rivers
- Water in the lakes
- Water in the seas
- Water in the Oceans
Underground water resources include water which has become underground through percolation or seepage and is lying in the porous rocks.
Water resources available on surface are not totally usable. Due to saltness, water available in seas and oceans is not usable. Only water found in rivers and lakes and underground water is usable. Underground water is obtained through bore well, artesian well, geysers and springs.
Utilisation
Water is used in numerous purposes:
- Drinking
- Bathing and Washing
- Irrigation
- Industries
- Navigation
- Generation of hydel power
- Fishing
- Numerous other purposes
Major multi-purpose river valley projects
After Independence our Government has formulated many projects in order to solve the problem of floods, irrigation and drainage. They serve numerous purposes simultaneously, hence they are known as Multi-Purpose Projects. Now several river valley projects have been executed in the country. Some of the purpose being served by these projects are:
q Irrigation.
q Flood control.
q Soil conservation.
q Generation of hydro-electricity.
q Development of inland water
ways.
q Afforestation in catchment area
of reservoirs.
q Development of fisheries.
q Provision of drinking water.
q Development of tourism.
q Modernisation of agriculture.
q Navigation and recreation.
q Development of wild lands to
preserve wild life.
water scarcity
97% of all water resources found on the earth is stored in oceans and seas. It is salty, only 3% of the total water resources is fresh water. ¾ of this 3% fresh water is found frozen in the form of ice sheets and glaciers. Lakes and rivers contain a very small quantity of water as compared to ground water resources.
The above reveals that there is an acute shortage of fresh water. Fresh water is used in drinking, bathing, washing, irrigation, industries and many more other purpose.
All over the globe water scarcity is experienced, specially during dry seasons.
Water scarcity is experienced in both the rural and urban areas. In rural areas people have to walk 3 to 11 kilometres to fetch fresh water for drinking.
Water Harvesting
In India rainy months are four—June to September. During this period an immeasurable quantity of water is wasted away as run off into the seas and oceans. If this rain water is made to use for man, he will never face water scarcity. Rain water can be utilised when it is needed for utilisation. Man keeping the rain water in reserve is termed as water harvesting. Water can be harvested in the following ways:
q By digging ponds and tanks.
q By building embankments and dams.
q By making arrangements for storage of rain water at rooftops.
q By constructing concrete underground reservoirs.
q By constructing reservoirs in parks and public places and covering them with concrete stabs.
q Buildings plans should invariably be approved only when there is a provision of water harvesting.
q Rural areas where open spaces are abundantly available should be encouraged water harvesting facilities and provisions.
Water so collected will be beneficial in more than one way:
q Collected water will be utilised in maintaining parks and greenery.
q It will be used in irrigation.
q It will recharge underground water resources through seepage and percolation.
q Water level will come up, thus resulting less cost of availing ground water.
q Humidity in soil will increase its fertility.
conservation and management of water
Water is life. Both natural and human systems are dependent on it. The primary requirement for survival as well as socio-economic development of human beings and a healthy eco-system, access to water plays a critical role in poverty and food security, both local and national.
Clean water for drinking and meeting other household needs is a necessity. However, in India we are facing daily challenges to met adequate water requirement. This problem is present not only in rural areas but also, in cities and towns.
