Water

Introduction

Water is one of the most abundantly found in natural resources. Without water life on earth is impossible. Water is an essential substance for all living organism. Green plants need water for photosynthesis and animals need water for drinking, bathing, washing, etc. Water is also known as the elixir of life.

Availability of Water

Water makes about 70% of the earth’s crust. It is a prime natural resource which is found on and under the ground.  Most of the (about 97%0) is in the seas and oceans as salt water. This water is too salty to be used for drinking and irrigation.  Thus, only 3% is available to us as fresh water. Out of this 2.997% is locked up in the mountains or glacier.

So, about only 0.003% of the fresh water is easily available to us in the form of groundwater, river, lake, stream, soil moisture, and water vapor for our need of water consumption.

Sources of Water

The various sources of water are as follows:

· Rainwater: Rain is the main source of water. It is considered to be the purest form of natural water. The rainwater also brings with it, the smoke and dust particles present in the atmosphere. Therefore, the first shower of rain contains many impurities.

· Oceans and seas: Almost 97% of all water is in the oceans. But this water is too salty to be used for drinking, farming, and irrigation.

· River and lakes: A part of rainwater falling on the earth’s surface runs down the slope of the land in the form of rivers and streams. In some rivers, water also flows in by melting of ice on the mountains.

· Groundwater: When it rains, a part of it seeps through a layer of soil. This water reaches solid rocks where it gets collected as groundwater. Groundwater can be obtained by drilling wells or sinking tube well to reach the water table.

Water Consumption

All living organisms need water to stay alive. But human beings depend on water more than plants and animals. In our day-to-day activities, we do water consumption for different purposes such as:

· Domestic uses: We need water for drinking, cleaning, cooking, washing, and some other activities. Each person may use an average of about 260 Liters of water a day in the house for different activities

· Industrial uses: Our industries use a large amount of water at different stages of production, from the use of water as a raw material to generate electricity. The uses vary from industry to industry.

· Agriculture uses: farmers depend largely on the water in the form of rainfall for higher production of crops. If there is not sufficient rainfall or irrigation facility, it greatly affects the agricultural production. Farmers use different irrigation methods to water the plants.

· Water for recreation and transport: People still depend on water transportation to carry heavy and bulky products as machinery, coal, grain, and oil. People build most of their recreation areas along lakes, rivers, and seas. They enjoy water sports such as swimming, fishing, and sailing.

States of Water

In nature, water exists in three states—solid (ice, snow, hail), liquid (water), and gas (water vapor). The three states of water are interchangeable, i.e., water can be changed from one form to another easily.

Water Cycle

The circulation of water from Earth’s surface to the atmosphere and back to earth is called water cycle. It is a cyclical process which repeats itself again and again. The different stages of the water cycle are as follows:

· Evaporation: It takes place when the sun heats up water in river, lakes or ocean and turns it into vapor or steam. The water vapor leaves the rivers, lakes, and oceans and goes into the air. About 90% evaporation is provided by the ocean, sea, lakes, and river. The remaining 10% is contributed by plant transpiration. Water vapor is water particles in gaseous form.

· Formation of a cloud: When warm air rises, it expands and cools. Cool air cannot hold as much water vapor in it as warm air; therefore some of the vapor condenses onto tiny dust particles floating in the air and form tiny water droplets around dust particles. These water droplets join together, they become a visible cloud.

· Condensation: When water vapors enter the air, the air cools and the water vapor changes back into liquid droplets, forming clouds. This process of change of water vapor into liquid droplets is called condensation.

· Precipitation: It occurs when the clouds become saturated with water vapor and heavy with water, the water falls back to the Earth in the form of rain, hail, or snow.

Conservation of Water

Sources of Water

Amongst most of the water, 97% is found in oceans and seas. The remaining, about 3% is found in rivers, lakes, ponds, streams, etc. Air also contains water.

Importance of Water

All plants, animals and human beings need water to stay alive. But human beings depend on water more than plants and animals. We need water for many other purposes such as: 

o We need water for the day -to- day activities such as bathing, cleaning, drinking, washing, etc.

o Water helps in the dispersal of seeds and fruits.

o It helps needed for irrigation.

o All industries use a large amount of water for cleaning, heating, cooling, generating electricity, as a raw material, etc.

o Water is used for transport and recreation too.

Water has properties of fluidity and solubility. These properties make it useful in the process of digestion, blood circulation and excretion. Water also helps in regulation of our body temperature by the process of sweating.

Scarcity of Water

Now the world is heading towards water crises due to the excessive and uneconomical use of water by the large human population. Human beings waste tons of water while brushing teeth, bathing, washing clothes, vehicles, and utensils etc. Overuse of water has led to a decrease in the supply of water available for human use.
Polluting water, deforestation and overpopulation have also disturbed the water cycle which, in turn, the annual rainfall varies in different parts of our country. If efforts are not made for managing and saving water, we are going to have an acute water crisis.

Conservation of Water

Conservation of water means a careful and economical use of water. We should conserve water as it is a precious natural resource. Conservation of water can happen in the following ways:

· Afforestation can help water to penetrate into the soil and replenish the water table

· Use of efficient watering systems such as drip irrigation and sprinklers to reduce water consumption by plants and help in conservation of water.

· Building Dams and hydropower projects which help in checking flood and regulating the supply of water to agriculture.

· Irrigation hours and frequency can be reduced.

· Treatment of industrial and domestic wastewater in sewage plants before its disposal in water bodies help in conservation of water. It reduces the water pollution.

Rainwater harvesting:

· In this system, the rainwater is collected by allowing it to flow from the rooftop through pipes in a storage tank. This water may contain some soil particles from the roof. So it should be filtered before use.

It is allowed to flow into a pit in the ground to recharge or refill the groundwater. Besides these, we should take the following steps for avoiding wastage of water at home:

· While taking water for drinking, we should take only just enough to quench our thirst.

· We should make economical use of water while taking a bath or washing clothes.

· The tap should be turned off immediately after the water is used.

· Inform the civic authorities on finding any water leak in public place.