ROLE OF WATER IN THE SOCIO-ECONOMIC DEVELOPMENT, ITS IMPORTANCE AND LINKS

By Pelekelo Liswaniso

WATER SUPPLY
Water is the most common substance on earth. It covers more than 70 per cent of the earth's surface. It fills the oceans, rivers, and lakes, and is in the ground and in the air we breathe. Water is everywhere. Regardless of language or culture, all humans share this basic need that is essential for survival.

We drink water, cook with it, bathe in it, sprinkle our lawns with it, fill our backyard swimming pools with it - even create theme parks based on it.

We, however, take its abundance for granted when much of the world, especially Sub-Saharan Africa, which includes Zambia, access to clean water is a luxury. More than half of Africa's villages lack access to a clean water supply. In many of these villages, women and children must walk up to ten miles every day carrying heavy buckets and containers to fetch the day's supply of potable water for their households. Those hours could be spent on other more profitable ways.

Without water, there can be no life. In fact, every living thing consists mostly of water. Your body is about two-thirds water. A chicken is about three-fourths water, and a pineapple is about four-fifths water. Most scientists believe that life itself began in water, in the salty water of the sea.

Animals share the same water sources as humans, doing neither any good. During the dry seasons, water supplies are inadequate or non-existent in many villages so that both people and cattle go thirsty while contaminated water is responsible for a myriad of health problems in the country including dysentery and malaria.

Ever since the world began, water has been shaping the earth. Rain hammers at the land and washes soil into rivers. The oceans pound against the shores, chiseling cliffs and carrying away land. Rivers knife through rock, carve canyons, and build up land where they empty into the sea. Glaciers plow valleys and cut down mountains.

Water helps keep the earth's climate from getting too hot or too cold. Land absorbs and releases heat from the sun quickly. But the oceans absorb and release the sun's heat slowly. So breezes from the oceans bring warmth to the land in winter and coolness in summer.

Throughout history, water has been people's slave - and their master. Great civilizations have risen where water supplies were plentiful. They have fallen when these supplies failed. People have killed one another for a muddy water hole.

They have worshiped rain gods and prayed for rain. Often, when rains have failed to come, crops have withered and starvation has spread across a land. Sometimes the rains have fallen too heavily and too suddenly. Then rivers have overflowed their banks, drowning large numbers of people and causing enormous destruction of property.

Today, more than ever, water is both slave and master to people. We use water in our homes for cleaning, cooking, bathing, and carrying away wastes. We use water to irrigate dry farmlands so we can grow more food. Our factories use more water than any other material. We use the water in rushing rivers and thundering waterfalls to produce electricity.

Our demand for water is constantly increasing. Every year, there are more people in the world. Factories turn out more and more products, and need more and more water. We live in a world of water. But almost all of it, about 97 per cent is in the oceans. This water is too salty to be used for drinking, farming, and manufacturing. Only about 3 per cent of the world's water is fresh (unsalted). Most of this water is not easily available to people because it is locked in icecaps and other glaciers. By the year 2000, the world demand for fresh water may be double what it was in the 1980's. But there will still be enough to meet people's needs.

There is as much water on earth today as there ever was or ever will be. Almost every drop of water we use finds its way to the oceans. There, the sun evaporates it. It then falls back to the earth as rain. Water is used and reused over and over again. It is never used up.

Although the world as a whole has plenty of fresh water, some regions have a water shortage. Rain does not fall evenly over the earth. Some regions are always too dry, and others too wet. A region that usually gets enough rain may suddenly have a serious dry spell, and another region may be flooded with too much rain.

Some regions have a water shortage because the people have managed their supply poorly. People settle where water is plentiful, near lakes and rivers. Cities grow, and factories spring up. The cities and factories dump their wastes into the lakes and rivers, polluting them. Then the people look for new sources of water.

Shortages also occur because some cities do not make full use of their supply. They have plenty of water but not enough storage tanks, treatment plants, and distribution pipes to meet the people's needs. As our demand for water grows and grows, we will have to make better and better use of our supply.

Water in our daily lives
Every plant, animal, and human being needs water to stay alive. This is because all the life processes, from taking in food to getting rid of wastes, require water. But people depend on water for more than just to stay alive. We also need it for our way of life. We need water in our homes, to brush our teeth, cook food, and wash dishes.

We need water in our factories to manufacture almost everything from automobiles to zippers. We need water for irrigation, to raise crops in regions that do not get enough rain.

Water in living things
All living things need a lot of water to carry out their life processes. Plants, animals, and human beings must take in nutrients (food substances). Watery solutions help dissolve nutrients and carry them to all parts of an organism. Through chemical reactions, the organism turns nutrients into energy, or into materials it needs to grow or to repair itself. These chemical reactions can take place only in a watery solution. Finally, the organism needs water to carry away waste products.

Every living thing must keep its water supply near normal, or it will die. Human beings can live without food for more than two months, but they can live without water for only about a week. If the body loses more than 20 per cent of its normal water content, a person will die painfully. Human beings must take in about 2.4 liters of water a day. This intake can be in the form of beverages we drink, or water in food.

Water in our homes
In our homes, we use far more water than the amount we need simply to stay alive. We require water for cleaning, cooking, bathing, and carrying away wastes. For many people, such water is a luxury. Millions of homes in Asia, Africa, and South America have no running water. The people must haul water up by hand from the village well, or carry it in jars from pools and rivers far from their homes.

WATER FOR IRRIGATION/AGRICULTURE
It is estimated that 70% of world-wide water use is for irrigation. In some areas of the world, irrigation is necessary to grow any crop at all, in other areas it permits more profitable crops to be grown or enhances crop yield. Various irrigation methods involve different trade-offs between crop yield, water consumption and capital cost of equipment and structures.

Irrigation methods such as most furrow and overhead sprinkler irrigation are usually less expensive but also less efficient, because much of the water evaporates or runs off. More efficient irrigation methods include drip or ttrikle irrigation, surge irrigation, and some types of sprinkler systems where the sprinklers are operated near ground level.
These types of systems, while more expensive, can minimize runoff and evaporation. Any system that is improperly managed can be wasteful.

In most countries including Zambia, people have had a rich heritage of managing and living with their environment including water since time immemorial and they have demonstrated to be effective custodians of water for agricultural purposes. Rainfall and water has been central to their lifestyles, and influencing their farming activities.

Most of the plants that people raise need great quantities of water. For example, it takes 115 gallons (435 liters) of water to grow enough wheat to bake a loaf of bread. People raise most of their crops in areas that have plenty of rain. But to raise enough food for their needs, people must also irrigate dry areas. The rainfall that crops use to grow is not considered a water use, because the water does not come from a country's supply. Irrigation, on the other hand, is a water use because the water is drawn from a nation's rivers, lakes, or wells.

The water a nation uses for irrigation is important to its water supply because none of the water remains for reuse. Plants take in water through their roots. They then pass it out through their leaves into the air as a gas called water vapor. Winds carry away the vapor, and the liquid water is gone. On the other hand, nearly all the water used in our homes is returned to the water supply. Sewer pipes to treatment plants, which return the water to rivers so it can be used again, carry the water.

WATERPOWER OR HYDRPOWER
Water power, or hydropower, furnishes about 7 percent of the world's commercial energy. Where water flows from a high place to a lower one, the gravitational energy of the falling water can be captured and used to produce other forms of energy. Most waterpower is used to generate electric power. Waterpower supplies energy without pollution and without using up the water in the process. But costly dams and other structures are required to harness waterpower.

People also use water to produce electric power to light homes and to run factories. Electric power stations burn coal or other fuel to turn water into steam. The steam supplies the energy to run machines that produce electricity. Hydroelectric power stations use the energy of falling water from waterfalls and dams to produce electricity.

In Zambia, electricity is relatively cheap due to the abundance of hydroelectric power sources as well as reasonably large coal reserves. Most of the electricity is supplied from major hydropower stations located in the Kafue Gorge, Lake Kariba north bank and the Victoria Falls as well as from the mini-hydro power stations in Lusiwashi, Musonda Falls, Chishimba Falls and Luzua. The domestic electricity supply is 240 volt, 50-hertz alternating current, with 415 volt single and three phase supply available for industrial use

WATER FOR INDUSTRY
It is estimated that 15% of world-wide water use is industrial. Major industrial users include power plants, which use water for cooling or as a power source (i.e. hydroelectric plants), ore and oil refineries, which use water in chemical processes, and manufacturing plants, which use water as a solvent.

The rivers, dams and lakes of Zambia are a source of water, food, electricity and recreation providing the engine of economic growth in various sectors. Zambia has a very large number of dams, which generate hydro- electrical power to various industries.

The industry in turn uses water in many ways. It uses water for cleaning fruits and vegetables before canning and freezing them. It uses water as a raw material in soft drinks, canned foods, and many other products. It uses water to air-condition and clean factories. But most of the water used by industry is for cooling. For example, water cools the steam used in producing electric power from fuel. It cools the hot gases produced in refining oil, and the hot steel made by steel mills.

Although industry uses a lot of water, only 6 per cent of it is consumed. Most of the water used for cooling is piped back to the rivers or lakes from which it is taken. The water consumed by industry is the water added to soft drinks and other products, and the small amount of water that turns to vapor in the cooling processes.

FISHERIES
Southern Africa’s in land water bodies also support a thriving inland fisheries industry. Fish catches vary from place to place, with the largest yields associated with major lakes and dams. The larger lakes, such as Victoria, Tanganyika and Malawi are quite productive in fish and provide almost the entire inland commercial and subsistence catches in the region, totaling 500,000 tonnes per year.

According to SADC, about 200,000 people are directly employed in the SADC inland fisheries industry. About 600,000-800,000 more are indirectly dependent on this industry and fish are often a large part of the diet of people living in the region including some parts of Zambia.

Floodplains, for example, are a very productive aquatic environment. Several thousand tonnes of fish are harvested annually from the floodplains such as the Barotse plains, which are part of the Zambezi in Western province of Zambia and the Kafue plains in Zambia, which yield about 11,000 tonnes of fish per year.

MINING
Mining contributes to over 50 percent of national economies of some member states in the Southern African region including Zambia, although it is a potential danger to the environment. Mining operations occur in a number of wetlands in the region, for example, the extraction of salt in Etosha (Namibia), gold panning along the Zambezi River and iron mining in the Kafue flats (Zambia).

The copper mines of Zambia for example, discharge waste in the Kafue River polluting the Lusaka swamps but mining continues because it is the engine of the economy contributing more than 80 per cent of Zambia’s foreign exchange earnings.

WATER FOR TRANSPORT/RECREATION

After people learned to build crude small boats, they began using rivers and lakes to carry themselves and their goods. Later, they built larger boats and sailed the ocean in search of new lands and new trade routes. Today, people still depend on water transportation to carry such 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. Many people also enjoy the beauty of a quiet lake, a thundering waterfall, or roaring surf.

ENVIRONMENT AND TOURISM
Explicit environmental water use is also a very small but growing percentage of total water use. Environmental water usage includes artificial wetlands, artificial lakes intended to create wildlife habitat, fish ladders around dams, and water releases from reservoirs timed to help fish spawn.
Like recreational usage, environmental usage is non-consumptive but may reduce the availability of water for other users at specific times and places. For example, water release from a reservoir to help fish spawn may not be available to farms upstream.

Water flowing from the mighty Victoria Falls is a spectacular sight in southern Africa and provides an array of tourism activities. The Falls lies between Zambia and Zimbabwe, about halfway between the mouth and the source of the Zambezi River.

The mist and spray created by the Falls can be seen from a great distance. This cloud and the constant roar caused the people of the area to name the Falls Mosi -oa -Tunya (smoke that thunders). British explorer David Livingstone sighted Victoria Falls in 1855. He named it in honor of Queen Victoria of Britain.

There are similar water falls elsewhere and rivers which all provide a source of tourism, generating huge financial resources and entertainment for the country. The Ku-omboka ceremony of the Barotse people of Western province is another toursit attraction which is observed every year drawing huge number of tourists to witness the Lozi King being paddled from the flooded plains of the Zambezi River at Lealui to high ground in Limulunga. The splash and flow of water in streams and fountains also soothes and inspires many people and they love to be near water to simply pass time and for leisure.

SANITATION
Sanitation is a field of public health. It involves various efforts to control the environment to prevent and control disease. Sanitation also includes personal cleanliness, which helps protect against disease and the presence of water is critical.

In most countries various government agencies work together to protect the health of communities. Sanitary engineers work in designing and administering water treatment plants and sewage treatment plants. Government agencies establish and enforce laws that help promote a healthful environment. Sanitation activities include food processing and distribution, sewage treatment, solid waste disposal, water treatment, and numerous other measures, such as control of air pollution and rodents.

Food processing and distribution
Food and beverages can easily be contaminated by bacteria, viruses, worms, and other organisms and by chemical poisons. Many agencies are involved in food and beverage control. For example, the department of Agriculture in most countries usually inspects meat before and after an animal is slaughtered. It also checks the processing, labeling, packaging, and distribution of food. The public health service provides communities with model laws that recommend requirements for producing, processing, and handling food. Some laws deal with pasteurization of milk and milk products.

Sewage treatment
Sewage is water containing waste matter produced by people. It contains about a tenth of 1 per cent solid waste. It comes from sinks and toilets in homes, farms, restaurants, factories, and office buildings. Much industrial sewage contains harmful chemicals and other waste materials.

Sewage must be treated before it flows from sewerage systems into lakes, rivers, and other bodies of water. Untreated sewage contaminates the water and, in time, can kill fish and aquatic plants. The sewage makes the water unsafe to drink and can also prevent use of the water for swimming, fishing, and other recreation.

Most cities and towns have at least one sewage treatment plant. In most rural areas, homeowners must provide their own sewage treatment. Most do so with large underground containers called septic tanks or pit latrines.

Solid waste disposal has become a major sanitation problem. Solid waste, which is also called refuse, consists of garbage and trash from cities and towns, plus by-products of farming, mining, and manufacturing. Such by-products include animal carcasses and manure from farms, sawdust and scrap metal from factories, and pieces of coal and various metals from mines.

Almost all methods of solid waste disposal can create environmental problems. For example, open dumps look unpleasant and may have a foul smell. They also provide homes for rats and other animals that carry disease. Burning solid waste causes smoke, which makes the air dirty. But when land disposal sites and incinerators are properly operated, they cause little harm to the environment.

Water treatment
Most water must be treated before it is used for drinking, cooking, bathing, or laundering. Almost all untreated water contains bacteria, viruses, and other tiny organisms. It also may have an unpleasant odor and taste and contain minerals that make the water less useful as a cleaning agent.

Cities and towns obtain water from one of two sources: (1) the ground or (2) rivers and lakes. Most communities get their water from the ground. Such water requires little treatment. Most of the larger cities get their water from rivers and lakes for various reasons. In many cities, for example, there is not enough water in the ground to supply the large population. Water from rivers and lakes is piped from its source to a treatment plant, where chemical and physical processes purify it. Pipes under the streets distribute the water to houses and other buildings.

Most communities have regulations that require dwellings, factories, hospitals, and recreation areas to meet certain sanitary standards. Sanitation also includes insect and rodent control, noise control, and licensing of operators of public facilities.

OWNERSHIP/WATER RIGHTS
In Zambia the ownership of all water is vested in the President while the responsibility of allocating water is delegated to the Minister responsible for water resource allocation. The Water Act of 1948 empowers the Minister to appoint a Board to allocate water to competing uses. The Water Board administers the provisions of the Act by issuing water rights to all users.

Water resources in Zambia is slowly becoming recognised as a strategic commodity, with supply limited in terms of quantity and demand increasing due to population growth and economic development. This has resulted in competition for the limited water resources between domestic, agricultural, environmental and hydropower use.

There is therefore no right of property in water. Everyone has the right to use water found in its natural channel in places where lawfully access may be. The Water Act puts water into two categories, private water and public water. For practical purposes all water found in watercourses whether visible or not is considered public. A watercourse consists in most cases of running water, which will find its way into a larger drainage system where access by others will be made. This determines its public nature.

Private water is loosely defined as that water which will not extend into a drainage system and hence inaccessible to the public. Under the Water Act all ground water is defined as private water. This, however, does not mean that it acquires characteristics of private property.

NATURE’S WATER CYCLE
The waters of the earth move continuously from the oceans, to the air, to the land, and back to the oceans again. The sun's heat evaporates water from the oceans. The water rises as invisible vapor, and falls back to the earth as rain, snow, or some other form of moisture. This moisture is called precipitation. Most precipitation drops back directly into the oceans. The remainder falls on the rest of the earth. In time, this water also returns to the sea, and the cycle starts again. This unending circulation of the earth's waters is called the water cycle or hydrologic cycle.

Because of nature's water cycle, there is as much water on earth today as there ever was or ever will be. Water changes only from one form to another, and moves from one place to another. The water you bathed in last night might have flowed in Russia's Volga River last year. Or perhaps Alexander the Great drank it more than 2,000 years ago.

The waters of the earth
The earth has a tremendous amount of water, but almost all of it is in the oceans. The oceans cover about 70 per cent of the earth's surface. They contain about 97 per cent of all the water on earth, and are the source of most precipitation that falls to earth. Ocean water is too salty to be used for drinking, agriculture, or industry. But the salt is left behind during evaporation, and the precipitation that falls to earth is fresh water. Only about 3 per cent of the water on earth is fresh water and most of it is not easily available to people.

Water in the air
At one time or another, all the water on earth enters the air, or atmosphere, as water vapor. This vapor becomes the life-giving rain that falls to the earth. Moisture in the air comes mostly from evaporation. The sun's heat evaporates water from land, lakes, rivers, and, especially, the oceans. About 85 per cent of the vapor in the air comes from the oceans. Plants also add moisture. After plants have drawn water from the ground through their roots, they pass it out through their leaves as vapor in a process called transpiration.

Precipitation
The air moving over the earth carries vapor. The moisture-filled air cools wherever it is forced up by colder air or by mountains or hills. As the air cools, the vapor condenses into droplets of liquid water, forming clouds. The droplets fall to the earth as rain. If the vapor is chilled enough, it condenses into ice crystals, and falls as snow.

About 75 per cent of the precipitation falls back directly on the oceans. Some of the rest evaporates immediately--from the surface of the ground, from rooftops, from puddles in the streets. Some of it runs off the land to rivers. From the rivers, it flows back to the sea. The rest of the precipitation soaks into the earth and becomes part of the ground water supply. Ground water moves slowly through the ground to the rivers and returns to the sea. This movement of ground water to rivers keeps the rivers flowing during periods without rain.


WORLD DISTRIBUTION OF WATER
The earth has an enormous amount of water, about 326 million cubic miles (1.4 billion cubic kilometers) of it. In a cubic mile, there are more than a million million--1,000,000,000,000 gallons, or 3.8 million million liters.

However, 97 per cent of this water is in the salty oceans, and more than 2 per cent is in glaciers and icecaps. The rest totals less than 1 per cent. Most of this water is underground, and the remainder includes the water in lakes, rivers, springs, pools, and ponds. It also includes rain and snow, and the vapor in the air.

A country's water supply is determined by its precipitation. In regions with plenty of precipitation year after year, there is plenty of water in lakes, rivers, and underground reservoirs.

The earth as a whole receives plentiful rain. If this rain fell evenly, all the land would receive 34 inches (86 centimeters) a year. But the rain is distributed unevenly. Generally, the world's most heavily populated areas receive enough rain for their needs. These areas include most of Europe, Southeast Asia, the Eastern United States, India, and much of China. But about half the earth's land does not get enough rain. These dry areas include most of Asia, central Australia, most of northern Africa, and the Middle East.