Essays on Water – This is one of the best essays on ‘Water’ especially written for school and college students.
Essay on Water
Essay Contents:
- Essay on the Introduction to Water
- Essay on the Forms of Water
- Essay on the Sources of Water
- Essay on Some Interesting Facts about Water
- Essay on the Water Cycle
- Essay on Water Treatment
- Essay on the Ancient Indian Methods of Water Conservation
Essay # 1. Introduction to Water:
When Neil Armstrong saw the Earth from the Moon, it appeared blue! This is because water covers more than two-thirds of the Earth’s surface. But fresh water represents less than 0. 5% of the total water on Earth. The rest is either in the form of seawater or locked up in ice caps or the soil, which is why one often hears of water scarcity in many areas.
Water is continuously moving around the earth and constantly changing its form. It evaporates from land and water bodies and is also produced by all forms of life on Earth. This water vapour moves through the atmosphere, condenses to form clouds and precipitates as rain and snow. In time, the water returns to where it came from, and the process begins all over again. Although water is constantly moving, its total quantity on Earth’s surface is constant.
Since water is referred as “elixir of life”, water pollution is by far the biggest environment problem, causing millions of death and so many illness per annum. Water pollution can be defined as the presence of foreign substances (organic, inorganic, biological or radiological) in water which tend to degrade its quality and constitute a hazard or impair its usefulness for drinking and domestic purpose or otherwise cause significant departures from the normal activities for various living communities.
National water commission stated that water is polluted if it has not been of sufficient high quality and found suitable for the higher uses people wish to make of it. According to researchers water pollution changes the quality of surface and sub-soil waters to such a degree that its suitability either for human consumption or for the support of man’s natural life processes decreases or ceases.
Essay # 2. Forms of Water:
Water is found in three different forms – liquid, solid or gas, depending on the temperature but it constantly changes from one form to another. Changes in temperature will determine which of these forms predominates in a particular area.
i. Liquid:
Water is usually encountered in the liquid state, because this is its natural state when temperatures are between 0°C and 100°C. ‘Fresh’ or drinking water is found as groundwater in underground aquifers, and on the surface in ponds, lakes, and rivers. Seas and oceans account for 97% of all water on Earth; but their waters contain dissolved salts and are therefore unfit to drink.
In regions of young volcanic activity, hot water emerges from the earth in hot springs (examples are Garampani in Assam and Badrinath in Uttaranchal). How does this phenomenon occur? Surface water percolates downward through the rocks below the Earth’s surface to high-temperature regions surrounding a magma reservoir, either active, or recently solidified but still hot. There the water is heated, becomes less dense, and rises back to the surface through fissures and cracks.
ii. Solid:
Ice is the frozen form of water. It occurs when temperatures are below 0°C (32°F). For a given mass, ice occupies 9% more volume than water, which is why when water enters cracks in rocks and freezes it causes the rocks to crack and split. Being less dense than water, ice floats.
This property of ice is vital to aquatic life in cold regions. As the temperature drops, ice forms a protective, insulating layer on the surfaces of streams, pools and other water bodies, allowing water to remain liquid in the layers beneath and life to survive. Glaciers, icebergs, and ice caps are all frozen water.
iii. Gas:
Water is found in the atmosphere in its gaseous form, water vapour. Steam is nothing but vapourized water. In certain hot water springs called geysers, jets of steam and hot water rise one hundred feet or more from the ground. Geysers are found in Iceland, the North Island of New Zealand and in USA’s Yellowstone National Park.
Worldwide, the consumption of water is doubling every 20 years – more than twice the rate of increase in population. A large amount of water is wasted in agriculture, industry, and urban areas. It has been estimated that with available technologies and better operational practices, agricultural water demand could be cut by about 50% and that in urban areas by about 33% without affecting the quality or economics of life. But most governments do not have adequate laws or regulations to protect their water systems.
Due to the increase in population there has been a rise in the demand for food, space for housing, consumer products, etc., which has in turn resulted in increased industrialization, urbanization, and demands in agriculture thereby leading to both river and groundwater contamination.
Essay # 3. Sources of Water:
Are you aware that only about 2.5 percent of the water on the Earth can be drunk? The balance 97.5 percent is salt water that we cannot use unless it is desalinated. Of the 2.5 percent that we can use, about three-fourths is frozen in the ice caps and glaciers, leaving just one quarter for household use. Freshwater is found in lakes, rivers, streams, underground, and glaciers. The world is heading towards a freshwater crisis due mainly due to its mismanagement. This crisis is already evident in many parts of the world, varying in scale and intensity depending on the time of the year, climate, and location.
Another reason for the depletion of freshwater resources, particularly groundwater resources, is a rapidly increasing human population.
Recognizing the importance of water resources to the planet’s future, the United Nations General Assembly proclaimed the year 2003 the International Year of Freshwater. This will provide an opportunity to raise awareness, motivate people, and mobilize resources in order to manage water in a sustainable way.
(i) Rivers:
Most ancient civilizations grew along the banks of rivers. Even today, millions of people all over the world live on the banks of rivers and depend on them for their survival.
All of us have seen a river—large or small, either flowing through our town, or somewhere else. Rivers are nothing more than surface water flowing down from a higher altitude to a lower altitude due to the pull of gravity. One river might have its source in a glacier, another in a spring or a lake. Rivers carry dissolved minerals, organic compounds, small grains of sand, gravel, and other material as they flow downstream.
Rivers begin as small streams, which grow wider as smaller streams and rivers join them along their course across the land. Eventually they flow into seas or oceans. Most rivers With the exception of the Nile, flow towards the Equator. The flow in most rivers is not uniform, which means that sometimes there are floods and sometimes no water flows in them. Flood control projects attempt to reduce the variation in flow.
Unfortunately most of the world’s major rivers are heavily polluted, but two of the world’s largest river systems—the Amazon, that drains a vast area of South America and the Congo in sub-Saharan Africa —remain relatively healthy. This is because both have few industries and a small human population in their watersheds.
Some facts about rivers:
(i) The Nile, 6695 km long, and the Amazon 6437 km long, are the world’s two longest rivers. Sometimes, measurements of their lengths can vary according to the criteria used for measurement.
(ii) An Arab philosopher and physician Avicenna suggested, nearly 1000 years ago, that landscapes changed largely as a result of the action of running water. His views were largely ignored until the 16th century.
(iii) The longest river in Asia is the Yangtze, which is 5472 km long.
(iv) The world’s highest waterfall are the Angel Falls in Venezuela, 979 m high, over 780 m of which is an uninterrupted drop.
Rivers in India:
India has a large number of rivers that are lifelines for the millions living along their banks.
These rivers can be categorized into four groups:
(i) Rivers that flow down from the Himalayas and are supplied by melting snow and glaciers. This is why these are perennial, that is, they never dry up during the year.
(ii) The Deccan Plateau rivers, which depend on rainfall for their water.
(iii) The coastal rivers, especially those on the west coast, which are short and do not retain water throughout the year.
(iv) The rivers in the inland drainage basin of west Rajasthan, which depend on the rains. These rivers normally drain towards silt lakes or flow into the sand.
(ii) Groundwater:
The importance of groundwater for the existence of human society cannot be overemphasized. Groundwater is the major source of drinking water in both urban and rural India. Besides, it is an important source of water for the agricultural and the industrial sector. Water utilization projections for 2000 put the groundwater usage at about 50%. Being an important and integral part of the hydrological cycle, its availability depends on the rainfall and recharge conditions.
Till recently it had been considered a dependable source of uncontaminated water. The demand for water has increased over the years and this has led to water scarcity in many parts of the world.
The situation is aggravated by the problem of water pollution or contamination. India is heading towards a freshwater crisis mainly due to improper management of water resources and environmental degradation, which has lead to a lack of access to safe water supply to millions of people. This freshwater crisis is already evident in many parts of India, varying in scale and intensity depending mainly on the time of the year.
Groundwater crisis is not the result of natural factors; it has been caused by human actions. During the past two decades, the water level in several parts of the country has been falling rapidly due to an increase in extraction.
The number of wells drilled for irrigation of both food and cash crops have rapidly and indiscriminately increased India-S rapidly rising population and changing lifestyles has also increased the domestic need for water the water requirement for the industry also shows an overall increase. Intense conducted competition among users-agriculture, industry, and domestic sectors is driving the groundwater table lower.
The quality of groundwater is getting severely affected because of the widespread pollution of surface water. Besides, discharge of untreated wastewater through bores and leachate from unscientific disposal of solid wastes also contaminates groundwater, thereby reducing the quality of freshwater resources.
As far as the quality of groundwater is concerned, many states in the country have been identified as endemic to fluorosis due to abundance in naturally occurring fluoride-bearing minerals. These are Andhra Pradesh, Gujarat, Haryana, Orissa, Punjab, Rajasthan, Tamil Nadu, Uttar Pradesh, Karnataka, Madhya Pradesh, Maharashtra, Bihar, and Delhi.
Nearly half million people in India suffer from ailments due to excess of fluoride in drinking water. In some districts of Assam and Orissa, groundwater has high iron content. About 31% of the total area of Rajasthan comes under saline groundwater.
Groundwater is saline in almost all of the Bhakra Canal in Punjab and the lift canal system in south-western Haryana. Similarly high levels of arsenic in groundwater have been reported in the shallow aquifers in some districts of West Bengal. Certain places in Haryana, Gujarat, and Andhra Pradesh were also found to have dangerously high levels of mercury.
(iii) Glaciers:
Glaciers are large sheets of ice that flow down very high mountains and are often the source of snow-fed rivers. Glaciers, found mainly in places such as Antarctica and Greenland, cover almost 10% of the earth’s landmass, varying in size. A glacier begins life as snowflakes.
As more snow falls and gathers, the weight of the snow on top compresses the lower layers to form ice. The pile of snow and ice becomes thicker and heavier till the point when the layer of ice at the very bottom melts under the pressure.
It re-freezes almost at once; but the process is repeated over and over, and as a result the entire mass begins to slide downhill slowly along the rock surface. A glacier has an enormous impact on the topography of the area, pushing aside boulders, cutting through rocks, and denting its path as it moves.
Most of the world’s glaciers are found at the Poles, but they exist on all of the world’s continents, even Africa. Australia doesn’t have any glaciers; however, it is considered part of Oceania, which includes several Pacific island chains and the large islands of Papua New Guinea and New Zealand. Both of these islands have glaciers. Glaciers require very specific geographical and climatic conditions.
Most are found in regions of high snowfall in winter and cool temperatures in summer. The amount of precipitation (whether in the form of snowfall, freezing rain, avalanches, or wind-drifted snow) is important to glacier survival. In areas such as Siberia and parts of Antarctica, the lack of adequate precipitation prevents glacier development.
Some facts:
(i) At presently, about 10% of the world’s land area is covered with glaciers.
(ii) Glaciers store about 75% of the world’s freshwater.
(iii) Glacierized areas cover over 15,000,000 square kilometres.
(iv) In the United States, glaciers cover over 75,000 square kilometres, with most of the glaciers located in Alaska.
(v) During the last Ice Age, glaciers covered 32% of the total land area.
(vi) If all land ice melted, the sea level would rise approximately 70 metres worldwide.
(vii) North America’s longest glacier is the Bering Glacier in Alaska, measuring 204 kilometres long.
(viii) The Malaspina Glacier in Alaska is the world’s largest piedmont glacier, covering over 8,000 square kilometres and measuring over 193 kilometres across at its widest point.
In India, glaciers are found in the Himalayas. There are about 15,000 glaciers flowing through these mountains, covering about 17% of the mountain area and supporting numerous perennial rivers such as the Ganga, Indus, and Brahmaputra.
Some well-known glaciers are described below:
1. Dokriani:
This glacier is believed to be as old as the Himalayan Mountains. Dokriani ‘Bamak’ is a well-developed medium sized glacier of the Bhagirathi basin. The glacier is 5 km long and flows in a northwest direction terminating at an elevation of 3,800 m. It originates at an altitude of 13,000 feet in Uttaranchal’s Garhwal district. It is one of the most studied glaciers in the world. A recent study says that it has been shrinking by a few metres every year.
2. Gangotri:
This is located in Uttaranchal’s Tehri Garhwal. One of the oldest glaciers in the Chaukhamba range, it is where the river Ganga originates. The Gangotri is not a single valley glacier, but a combination of several other glaciers that are fed to it and form a huge mass of ice. The glacier covers 28 km and terminates at Gaumukh (4,000 m).
3. Pindari:
This is one of the most beautiful glaciers in the Kumaon hills and is known as the Jewel of Kumaon. It is located at a height of 13,000 feet above sea level between the Nanda Devi and Nandakot peaks and terminates at an altitude of 3,627 m. It is 5 km long, the snout is about 6 m high and 2.5 m wide and above the snout, the glacier extends for about 3 m. The Pinder River that emerges from the Pindari glacier drains the valley.
4. Zemu:
The Zemu glacier is the largest and most famous glacier in the eastern Himalayas, with a length of about 26 km. It is located in northwestern Sikkim in a U-shaped valley at the base of the Kanchenjunga massif. The Teesta river has its source in this glacier. Many tributary glaciers feed the trunk glacier.
5. Siachen:
This is the largest glacier in the world outside the Polar regions, stretching over a length of about 72 km. It lies in the extreme north-central part of Jammu and Kashmir near the border of India and Tibet, on the north-facing slopes of the Karakoram Range, and feeds the Shaksgam river that flows into Tibet.
The glacier can be approached from Skardu in Ladakh. To the east of the Siachen lies a group of three glaciers known as the Rimo North, Central, and South. Between them, these glaciers have almost 700 square km of ice, which, at places, is 100 m deep. Altogether, the glaciers contain about 200 cubic kilometres of ice.
(iv) Lakes:
A lake is a low-lying part of the Earth’s surface in which rainwater, surface water run-off, outflow from a river, and water from other sources accumulates. There is a great variety of lakes on Earth; there are freshwater lakes and saltwater lakes, ranging in size from small fish-ponds to huge water bodies such as Lake Superior in USA which is the world’s largest freshwater lake. The Caspian Sea in Europe and the Sambhar lake in Rajasthan are examples of saltwater lakes.
India has a large number of lakes spread all over the country, from Kashmir to Kerala and from Rajasthan to Assam. Among the better-known freshwater lakes in India are the Dal lake in Srinagar and the Nainital lake. Whether natural or manmade, all lakes are major sources of water. Lakes are homes to a large variety of aquatic life, with one notable exception; the Dead Sea, a saltwater lake in Israel does not have any form of life. There is too much salt in its water to sustain life.
Almost half of the world’s lakes are degraded, depleted, and contaminated mainly by human activities. The main causes are inflow of domestic sewage, agricultural run-off, discharge of industrial effluents, over-fishing, introduction of exotic species and habitat degradation from population growth, expansion of cities.
As more water is withdrawn for human use and more of it is returned to lakes and rivers badly polluted there is less available to maintain vital freshwater ecosystems.
(v) Urban Wetlands:
Through the ages, urban wetlands have been the lifeline of most cities in India. They were preserved and looked after by the people as their main source of water supply for drinking and irrigation. These wetlands are found all over the country and are either natural or built by people. Over the years, they have gradually depleted, leading to a number of problems in urban areas such as flooding, water scarcity, and water logging.
Tanks were constructed in the catchment areas of cities that were not located near a river or a large lake. Rainwater or run-off would collect during the monsoons and be stored for the rest of the year in these tanks and lakes. The city would get its water supply from these.
In southern India, the towns were built around a temple, which always had a tank at the centre. Wells were located in the tank, which served as a link with the aquifers. There were innumerable tanks dug by the rulers, most of which have been destroyed. In fact, in some areas tank building by the ruler was considered a noble deed.
In Karnataka, the Hoysalas built tanks all over the state. Some of these still exist. Festivals were organized around tanks; cleaning and de-silting the tanks were a part of the rituals. But over the years, human activity steadily destroyed these wetlands. In Bangalore, the city bus terminus has been built on the Dharmambudhi tank. A part of the Sampangi tank has given way to the Kanteerva stadium and the remaining to a housing colony.
Another lake was filled up to house the city market:
i. Pollution levels in the Hussain Sagar Lake in Hyderabad has been going up over the years. There are more than a thousand polluting industries located around the lake, a large number of them pharmaceutical industries. Untreated effluents from the industries and domestic sewage have deteriorated the water quality in the lake. The lake gets little chance to rejuvenate itself as a run-off happens only once a year during the monsoons, whereas pollutants flow in throughout the year.
ii. The Cholas were well known for the construction of tanks in the state of Tamil Nadu. But today, despite heavy rains, Chennai reels under severe water crisis along with flooding. A number of housing colonies have been built on tanks and over the years the numbers are increasing. This is the case in most large cities in the country.
iii. In Calcutta wetlands, both artificial and natural, have been a part of the city system. The main drainage for the city has been the Hooghly River; but the incline of the city is eastwards and this has led to the creation of the East Calcutta Wetlands. The Salt Lake is one of the largest wetlands in the city and serves as a flood cushion for the city. Calcutta has no sewage treatment plant. The sewage is treated in the sewage-fed fisheries; the process is cost-effective and lasting. A number of the fisheries purify this water through a series of sedimentation tanks and use the water for fish cultivation and agriculture.
iv. Indore’s water needs were met by a large numbers of wells and tanks located all around the city. But over the last few years, the tanks have gradually dried up, including the largest of them, the Yashwant Sagar Lake. Vegetable and fruit cultivation along the banks of the lake has caused pollution due to run-offs from the fields. This has caused eutrophication and contamination.
v. There are no rivers in the vicinity of Bhopal and the city depends entirely on lakes to meet the water needs of the city. Over the years, these lakes have become polluted due to the dumping of sewage into them. The government recently announced the Bhuj Wetland Project, a scheme to prevent the flow of liquid and solid waste into the lakes and also to de-sill them. More than 2000 ha of land around the upper lakes, which feed water to the lower ones, is to come under plantation.
Once upon a time, these urban wetlands maintained a steady supply of water for the city, recharged the groundwater, cooled the city, and prevented flood as they were a natural drainage system. Over the years, these very tanks and wetlands have been neglected, encroached upon either to accommodate more houses or to dump waste. This has caused large-scale water crisis and monsoon flooding and water logging, leading to misery and disease. These wetlands that have been protected for centuries are now being ravaged and destroyed in the name of development.
People in the urban areas must learn to live in harmony with nature in their own habitat. The wetlands, the green belts, and the flora and fauna of these areas have to be preserved for urban areas to survive and remain healthy.
Essay # 4. Some Interesting Facts about Water:
(i) 75% of the earth’s surface is covered with water,
(ii) More than 97% of the earth’s water is in its oceans,
(iii) About 2% of the available drinking water is frozen leaving only 1% for drinking,
(iv) The world’s average rainfall is about 850 mm,
(v) Water regulates the Earth’s temperature. It also regulates the temperature of the human body, carries nutrients and oxygen to cells, cushions joints, protects organs and tissues, and removes waste,
(vi) 60% – 75% of the adult human body is water – 82% of blood is water; 70% of the brain and 90% of the lungs are made up of water,
(vii) Blood in animals and sap in plants is composed mainly of water,
(viii) To cook 1 cup of rice you need 2 cups of water but to wash the pan in which it has been cooked you need 4-5 litres of water,
(ix) A dripping tap can waste up to 6 litres of water in a day,
(x) More than half the creatures on the Earth are found under water Life on earth probably originated in water,
(xi) In the summer our bodies require about 2 litres of water daily. Here is the water content of some foods (approximate) – 95% in tomato, 91% in spinach, 91% in milk, 85% in apples and 80% in potatoes, and
(xii) 10% of the earth’s surface is covered with ice.
There are more than one billion people particularly in North Africa and Western and South Asia, who lack access to a steady supply of clean water.
Access to water and sanitation, so crucial to human well-being and development, has now become a priority for the international community. To underscore the need for immediate action, the United Nations has designated 2003 as the International Year of Freshwater.
The importance given to water in ancient India is reflected in several hymns of the Vedas and epics and narratives from other valuable works such as the Arthasastra of Kautilya.
Essay # 5. Water Cycle:
The different water sources of the earth get their water supply from precipitation, while this precipitation in itself is the evaporation from these sources. Water is lost to the atmosphere as vapour from the earth, it condenses and then precipitates back in the form of rain, snow, hail, dew, frost or sleet. This is the hydrologic cycle that continues forever thereby maintaining a balance between the two.
Essay # 6. Water Treatment:
Today, people are becoming more aware of the importance to drinking water, with that awareness comes the concern about the quality of water they are drinking, water that looks drinkable can contain harmful substances that may cause illness if ingested.
Communities get their water from rivers and lakes (surface water), from springs and wells (groundwater) or from both surface and ground, these sources of freshwater makes up less than 1% of the total water resources on earth. About 97% of the water on earth is found in the oceans. Most of the rest is frozen in the polar ice caps and in glaciers.
Water purification is a process of removing harmful substances and odor from a raw water source. Water that looks drinkable can contain harmful substances that may cause illness if ingested. Surface water may be polluted by sewage, industrial wastes, or dead plants and animals. Groundwater may be polluted by leaks from sewage or industrial wastes. Both surface water and groundwater may also contain other solids and may have objectionable tastes and odors.
Methods of Water Treatment:
1. Intake Filtering:
In this method raw or untreated water usually enters a water-treatment plant through a pipeline or tunnel. A series of screens prevents debris from entering the water-treatment system.
2. Chemical Treatment:
In this method the raw water is pumped into a discharge basin and then given several types of chemical treatment. Disinfectants like chlorine, chlorine dioxide, iodine, or ozone are added in controlled amounts to kill bacteria and other organisms. When chlorine is used, activated carbon or ammonia is usually also added to remove the taste of chlorine from the water.
Fluorides are sometimes added to the water to help prevent tooth decay. Water containing calcium or magnesium (hard water) is treated to remove these minerals this process is called water softening. To prevent the corrosion of pipes, lime or caustic soda is sometimes added to acidic water.
3. Sedimentation:
This method is often used as a first stage in modern wastewater treatment plant. This process consists of allowing matter suspended in the water to settle. Coagulant like aluminum sulfate is added to the water to speed up the sedimentation process by causing small particles to cling together, forming clumps called floe. Water that has been treated with coagulant is gently stirred in a mixing basin before it passes into settling basin. The stirring promotes the formation of the floe. In the settling basin, the water flows slowly and the froc gradually settles forming sludge (thick mud) at the bottom of the basin.
4. Filtration:
After separating most floe the water is filtered as the final step to remove remaining suspended particles, water passes on to filter beds. They are usually made up of a layer of gravel 18 to 24 inches (45 to 60 cm) thick covered with sand or crushed anthracite in a layer 24 to 30 inches (60 to 75 cm) thick.
As the water drains, the filter trap remaining particles suspended in the water. Drains carry the filtered water to a reservoir. To clean the filter beds, water is passed quickly upward through the filter from below (opposite of the normal direction) with filtered water to remove embedded particles. The wash water is then removed through special drains.
5. Aeration:
This is done either before or after filtration, the water may be aerated (exposed to the air) to remove unpleasant odors and tastes caused by decomposing organic matters, industrial wastes and some gases. It is also effective in removing radon (gaseous element formed by the radioactive decay of radium) from water. In the process, oxygen in the air combines with foul-smelling substances to change them into odorless compounds.
Things to consider when selecting a purification solution:
The list of water purification solutions below is designed for people who would like to have protection at home or work from actual or potential contaminants in the water they drink.
In order to determine which of the solutions is best for your needs you might want to consider the following:
i. How much purified water you would like to use per day for drinking and cooking (a family of four will probably use 4 to 8 gallons per day).
ii. Which contaminants are actually in your water (and which ones might occasionally show up). The only way to know this for sure is to request a report from your water supplier or have your water tested.
iii. Which contaminants you are interested in removing. The plan I adopted was to go with a solution that would provide the best protection from most of the potential contaminants (for the lowest cost and least maintenance) – even though most of the contaminants are not currently present in my tap water.
iv. The cost of the solution you decide upon, both the initial cost (which may be high for some filtration systems, ion exchange units, distillers, etc.,) and the ongoing costs (which might be high for distillers, bottled water, etc.). Look at the total amount you will spend over the next 10 to 40 years based on the amount of pure water you would like to be able to use for drinking, cooking, washing foods, etc.
v. The value of the product. Is the product certified to perform as advertised (or in the case of bottled water, is it certified to be free of contaminants). Does the product provide you with safe, good tasting water at a reasonable cost. Is there minimal maintenance required.
Essay # 7. Ancient Indian Methods of Water Conservation:
“The Indus Valley Civilization, that flourished along the banks of the river Indus and other parts of western and northern India about 5,000 years ago, had one of the most sophisticated urban water supply and sewage systems in the world. The fact that the people were well acquainted with hygiene can be seen from the covered drains running beneath the streets of the ruins at both Mohenjodaro and Harappa.
Another very good example is the well-planned city of Dholavira, on Khadir Bet, a low plateau in the Rann in Gujarat. One of the oldest water harvesting systems is found about 130 km from Pune along Naneghat in the Western Ghats. A large number of tanks were cut in the rocks to provide drinking water to tradesmen who used to travel along this ancient trade route. Each fort in the area had its own water harvesting and storage system in the form of rock-cut cisterns, ponds, tanks and wells that are still in use today.
A large number of forts like Raigad had tanks that supplied water:
i. In ancient times, houses in parts of western Rajasthan were built so that each had a rooftop water harvesting system. Rainwater from these rooftops was directed into underground tanks. This system can be seen even today in all the forts, palaces and houses of the region.
ii. Underground baked earthen pipes and tunnels to maintain the flow of water and to transport it to distant places, are still functional at Burhanpur in Madhya Pradesh, Golkunda and Bijapur in Karnataka, and Aurangabad in Maharashtra.
(i) Rainwater Harvesting:
In urban areas, the construction of houses, footpaths and roads has left little exposed earth for water to soak in. In parts of the rural areas of India, floodwater quickly flows to the rivers, which then dry up soon after the rains stop. If this water can be held back, it can seep into the ground and recharge the groundwater supply.
This has become a very popular method of conserving water especially in the urban areas. Rainwater harvesting essentially means collecting rainwater on the roofs of building and storing it underground for later use. Not only does this recharging arrest groundwater depletion, it also raises the declining water table and can help augment water supply. Rainwater harvesting and artificial recharging are becoming very important issues. It is essential to stop the decline in groundwater levels, arrest sea-water ingress, i.e., prevent sea-water from moving landward, and conserve surface water run-off during the rainy season.
Town planners and civic authority in many cities in India are introducing bylaws making rainwater harvesting compulsory in all new structures. No water or sewage connection would be given if a new building did not have provisions for rainwater harvesting. Such rules should also be implemented in all the other cities to ensure a rise in the groundwater level.
Realizing the importance of recharging groundwater, the CGVVB (Central Ground Water Board) is taking steps to encourage it through rainwater harvesting in the capital and elsewhere. A number of government buildings have been asked to go in for water harvesting in Delhi and other cities of India.
All you need for a water harvesting system is rain, and a place to collect it! Typically, rain is collected on rooftops and other surfaces, and the water is carried down to where it can be used immediately or stored. You can direct water run-off from this surface to plants, trees or lawns or even to the aquifer.
Some of the benefits of rainwater harvesting are as follows:
(i) Increases water availability.
(ii) Checks the declining water table.
(iii) Is environmentally friendly.
(iv) Improves the quality of groundwater through the dilution of fluoride, nitrate, and salinity.
(v) Prevents soil erosion and flooding especially in urban areas.
(ii) Agriculture:
Conservation of water in the agricultural sector is essential since water is necessary for the growth of plants and crops. A depleting water table and a rise in salinity due to overuse of chemical fertilizers and pesticides has made matters serious. Various methods of water harvesting and recharging have been and are being applied all over the world to tackle the problem. In areas where rainfall is low and water is scarce, the local people have used simple techniques that are suited to their region and reduce the demand for water.
i. In India’s arid and semi-arid areas, the ‘tank’ system is traditionally the backbone of agricultural production. Tanks are constructed either by bunding or by excavating the ground and collecting rainwater.
ii. Rajasthan, located in the Great Indian Desert, receives hardly any rainfall, but people have adapted to the harsh conditions by collecting whatever rain falls. Large bunds to create reservoirs known as khadin, dams called johads, tanks, and other methods were applied to check water flow and accumulate run-off. At the end of the monsoon season, water from these structures was used to cultivate crops. Similar systems were developed in other parts of the country. These are known by various local names ¾ jal talais in Uttar Pradesh, the haveli system in Madhya Pradesh, ahar in Bihar, and so on.
(iii) Reducing Water Demand:
Simple techniques can be used to reduce the demand for water. The underlying principle is that only part of the rainfall or irrigation water is taken up by plants, the rest percolates into the deep groundwater, or is lost by evaporation from the surface. Therefore, by improving the efficiency of water use, and by reducing its loss due to evaporation, we can reduce water demand. There are numerous methods to reduce such losses and to improve soil moisture.
Some of them are listed below:
(i) Mulching, i.e., the application of organic or inorganic material such as plant debris, compost, etc., slows down the surface run-off, improves the soil moisture, reduces evaporation losses and improves soil fertility.
(ii) Soil covered by crops, slows down run-off and minimizes evaporation losses. Hence, fields should not be left bare for long periods of time.
(iii) Ploughing helps to move the soil around. As a consequence it retains more water thereby reducing evaporation.
(iv) Shelter belts of trees and bushes along the edge of agricultural fields slow down the wind speed and reduce evaporation and erosion.
(v) Planting of trees, grass, and bushes breaks the force of rain and helps rainwater penetrate the soil.
(vi) Fog and dew contain substantial amounts of water that can be used directly by adapted plant species. Artificial surfaces such as netting-surfaced traps or polyethylene sheets can be exposed to fog and dew. The resulting water can be used for crops.
(vii) Contour farming is adopted in hilly areas and in lowland areas for paddy fields. Farmers recognize the efficiency of contour-based systems for conserving soil and water.
(viii) Salt-resistant varieties of crops have also been developed recently. Because these grow in saline areas, overall agricultural productivity is increased without making additional demands on freshwater sources. Thus, this is a good water conservation strategy.
(ix) Transfer of water from surplus areas to deficit areas by inter-linking water systems through canals, etc.
(x) Desalination technologies such as distillation, electro-dialysis and reverse osmosis are available.
(xi) Use of efficient watering systems such as drip irrigation and sprinklers will reduce the water consumption by plants.
(iv) Daily Habits:
The most important step in the direction of finding solutions to issues of water and environmental conservation is to change people’s attitudes and habits 3/4 this includes each one of us. Conserve water because it is the right thing to do.
We can follow some of the simple things that have been listed below and contribute to water conservation:
(i) Try to do one thing each day that will result in saving water. Don’t worry if the savings are minimal 3/4 every drop counts! You can make a difference.
(ii) Remember to use only the amount you actually need.
(iii) Form a group of water—conscious people and encourage your friends and neighbours to be part of this group. Promote water conservation in community newsletters and on bulletin boards. Encourage your friends, neighbours and co-workers to also contribute.
(iv) Encourage your family to keep looking for new ways to conserve water in and around your home.
(v) Make sure that your home is leak-free. Many homes have leaking pipes that go unnoticed.
(vi) Do not leave the tap running while you are brushing your teeth or soaping your face.
(vii) See that there are no leaks in the toilet tank. You can check this by adding colour to the tank. If there is a leak, colour will appear in the toilet bowl within 30 minutes. (Flush as soon as the test is done, since food colouring may stain the tank.)
(viii) Avoid flushing the toilet unnecessarily. Put a brick or any other device that occupies space to cut down on the amount of water needed for each flush.
(ix) When washing the car, use water from a bucket and not a hosepipe.
(x) Do not throw away water that has been used for washing vegetables, rice or dals3/4use it to water plants or to clean the floors, etc.
(xi) You can store water in a variety of ways. A simple method is to place a drum on a raised platform directly under the rainwater collection source. You can also collect water in a bucket during the rainy season.
What we can do to conserve water?
1. Use only as much water as you require.
2. Close the taps well after use.
3. While brushing your teeth do not leave the tap running, open it only when you require it.
4. See that there are no leaking taps. Get a plumber to come in and seal all leaks.
5. Use a washing machine that does not consume too much water.
6. Do not leave the taps running while washing dishes and clothes.
7. Install small shower heads to reduce the flow of the water.
8. Water in which the vegetables and fruits have been washed can be used to water the flowers and ornamental potted plants.
9. At the end of the day if you have water left in your water bottle do not throw it away, pour it over some plants.