Monitoring The UN

Monitoring The UN > The UN and Sustainable Development

Freshwater Resources
UNA-Canada's "On the Road to Brazil" Series
-Issue Paper No.7-

Fresh Water: An Introduction

Water is the lifeblood of the environment, essential to the survival of all living things. Although water covers nearly three quarters of the earth’s surface in oceans as well as rivers, lakes, snow and glaciers, less than five per cent of this total exists as fresh water. Furthermore, all but a tiny fraction of fresh water is either permanently frozen or underground.

The freshwater supply is in continual motion through the hydrologic cycle, the endless circulation of water between the ocean, air and land. Each year, the sun’s heat causes some 500,000 cubic kilometres of water from the earth’s surface to evaporate -- 86% from the ocean and 14% from land. An equal amount falls back to earth as rain, sleet, hail, or snow, but the process returns more water to the land than is evaporated from it. The World Resources Institute estimates that this cycle distills and transfers 41,000 cubic kilometres of water from the oceans to the continents annually. To complete the natural cycle, the water then makes its way back to the ocean as runoff.

Of this 41,000 cubic kilometres of water, almost two-thirds returns to the ocean as flood runoff and is untappable. Another 5,000 cubic kilometres flow through uninhabited areas. The remaining 9,000 cubic kilometres constitutes the practical limit of the world’s renewable freshwater supply.

Is There Enough Water to Meet Our Needs?

If the supply of freshwater was equally distributed, it would be more than adequate to sustain the world’s rapidly growing population as well as the many other animals and plants which depend upon access to and use of this resource. However, because both the freshwater supply and the world’s population are unevenly distributed, there are many regions which suffer from severe water shortages.

By comparing evaporation and precipitation rates, it is possible to identify water-rich and water-poor countries. Eighty countries comprising 40% of the world’s population are already experiencing serious water shortages. Africa and Asia are the continents facing the greatest water shortages. In Africa, 30 million people have suffered malnutrition attributable to the drought of recent years. In Asia, per capita freshwater supplies are less than half the global average.

Even a water-rich country such as Canada, which possesses close to nine per cent of the world’s renewable freshwater supply, suffers from geographic disparities. Some areas in the interior of British Columbia, southern prairies, and the high Arctic receive less than 35 centimetres of annual precipitation. In addition, two-thirds of Canada’s rivers flow runs northward, while 80% of the population lives within 200 kilometres of the Canada-US border, a situation which results in occasional water shortages. Even in the Great Lakes basin, the world’s largest freshwater lake system, some areas in southern Ontario experience periodic water shortages.

In addition to distribution, it is important to look at how the water is used when considering the question of adequate supply. While many uses do little to disturb water’s natural cycle, other uses -- such as agricultural, industrial and household uses -- can dramatically reduce a region’s immediate water supply. Most of the water used for irrigation, for example, returns to the atmosphere through evaporation and is not available for further use locally. A farmer whose sprinklers operate on well water may cause a net reduction in his region’s groundwater supply. Averaged globally, 73% of the freshwater withdrawn from the ground is used for agriculture. As a consequence of its use in agriculture, depletion of groundwater is common in India, China and parts of the United States.

Supply problems can also occur through competing uses of the same water. While most household and industrial uses withdraw water from its source and then return all or most of it downstream, shortages may arise at peak periods when overall demand exceeds supply. In this regard, withdrawal rates per person are important. Canadians, for example, are among the biggest water users in the world. The average Canadian resident uses more than 70 times as much water every year as the average resident of Ghana does. As population, industry, and agriculture expand, water for all uses will become increasingly scarce.

There are only tow ways to reduce local water shortages. The first is by increasing local supply, either by damming rivers or by withdrawing more groundwater. Since the renewable freshwater supply of an area is finite, if withdrawal continues to exceed recharge, this is essentially a short term solution. The second, and more sustainable, solution is to increase the efficiency of water use, thereby conserving feshwater supplies locally.

The Importance of Water Quality

Assuring an adequate supply of freshwater is not the only problem facing many countries throughout the world. There is also the serious problem of quality. Water quality has long been an issue in the developing world where three out of five persons lack access to clean water supplies. It has been estimated that contaminated water and poor sanitation cause 30,000 deaths around the world every day -- that’s the equivalent of 100 jumbo jets crashing daily. The severity of the problem is such that the United Nations declared the 1980’s to be the International Drinking Water Supply and Sanitation Decade and instituted a programme to provide safe drinking water and appropriate sanitation for everyone by 1990.

Yet although considerable progress has been made in countries as diverse as Indonesia, Ghana and Mexico, the recent outbreak of cholera in Peru bears terrible witness to the fact that the ambitious goals of the decade were far from being met. Population growth, particularly in urban areas of developing countries during the decade provided an unexpected challenge. One of the significant conclusions of the decade is that the solution to ensuring safe drinking water supplies lies not just with the application of technology but with better trained people able to manage adequately water in all of its uses through an integrated approach to water management.

Although many factors affect water quality, the two major sources of freshwater pollution are traditional organic waste (human and animal excrement) and the toxic wastes generated by industry and the products of industry. Organic wastes are biodegradable, but become a problem when the quantity of waste exceeds the capacity of the water to purify itself. In India, for example, only 217 of the country’s 3,119 towns and cities have even partial sewage-treatment facilities, according to a 1986 study by the World Resources Institute. As a result, an estimated 70% of India’s total surface water is polluted.

Toxic pollution -- the contamination of freshwater by chemicals, radioactive materials, and heavy metals -- is the most rapidly growing type of freshwater pollution. A toxic substance may be termed persistent or non-persistent depending on how long it takes to break down. Both persistent and non-persistent contaminants can be harmful. Because of their longevity, however, persistent toxic substances have the greatest probability of accumulating up the food chain to hazardous levels. Once in the water, persistent substances are absorbed or eaten by micro-organisms. Large numbers are then consumed by the next level of the food web where concentration of the toxicant increases. While toxic pollution is most often associated with industry, pesticides used to improve crop yields are also a major problem.

In most newly industrialized countries, both organic and toxic pollution are on the rise. This is due in part to the use of pesticides to feed a growing population and the desire for economic growth which have been given higher priority than the reduction of pollution.

The problem of water quality is not restricted to developing nations. One need look no further than the Great Lakes to see the severity of freshwater pollution in the industrialized world. More than 300 chemical compounds, many dangerous to human health, have been found in the water. Cancerous tumours, thought to be linked to toxic contamination, have been found in fish of Lake Ontario. Similarly, two rivers in the south of the Soviet Union have been virtually killed by the pesticide-laden run off from nearby cotton fields. The area has the highest infant mortality rate in the country, which is attributed primarily to the infection and disease spread by its contaminated water.

How Can We Protect This Vital Resource?

To some extent, both the quantity and quality of freshwater resources are managed worldwide. Unfortunately, the results -- particularly in terms of quality -- have been inadequate. Organic pollution is widespread in less developed countries resulting every year in the unnecessary deaths of millions of people -- and children in particular -- from typhoid, cholera, and other water-borne diseases. Diarrheal diseases result in the death of about five million infants and children annually. In developed countries, toxic chemicals are freshwater’s greatest threat, emanating from effluent pipes and smoke stacks of factories, seeping into groundwater from landfill sites and running off agricultural land into surface and ground water. Globally, 25% of our rivers are dangerously polluted, as are hundreds of thousands of lakes.

In summary, developing countries face two main problems: 1) there is a shortage of water for agriculture; and 2) many people lack safe drinking water and basic sanitation. The main problem for industrialized countries is pollution of the water resources, which has an impact on drinking water and on the proper functioning of aquatic ecosystems.

In order to protect the world’s freshwater and ensure clean water for all, it will be necessary to clean up the pollution that is already strangling the waterways; clamp down harder on new discharges of such poisons; and continue to educate the world population about humanity’s responsibility for this life-sustaining resource.

The degradation of the world’s freshwater has no respect for boundaries; after all, everyone draws from the same finite supply of renewable water. Protection, therefore, depends on closer cooperation between governments, whether the money spent will have an immediate benefit domestically or not.

The Mar del Plata Action Plan, which was worked out under UN auspices almost fifteen years ago, provides an overall action framework for the entire international community. Some limited progress has been achieved under this framework, most notable the accomplishments of the International Decade on Water Supply and Sanitation which was one of the key recommendations of the Mar del Plata Action Plan, but numerous gaps remain. Uncontrolled events, such as a global recession, large urban population growth in the developing world and severe drought in Africa, impeded progress in implementing the Mar del Plata plan. Other problems have been widely identified, such as lack of funds and well-trained technicians and managers. It is hoped that the 1992 UN Conference on the Environment and Development will be able to deal with these discrepancies effectively.

Issues for UNCED