Note: Because some of the information in this article may be outdated, it has been archived.
The local water authority in Baraka constructed a 30km piped water system, which provides more than 30,000 people with drinking water. Photographer: Julien Harneis, Creative Commons
Editor’s Note: A major report, “Global Environment Outlook 3,” by the United Nations Environment Programme (May 2002), cautions that without action more than 70 per cent of the earth’s land surface could be affected by the impact of development within 30 years and more than half of all people could be living in severely water-stressed areas by 2032. The author’s call for action to address freshwater shortages is now even more urgent.
About 35% of the world has a drastic shortage of drinking water.
Science is not giving the issue of water technologies enough attention. I would like to make a plea for an international facility for research and technological development to increase our share of global waters.
Shortages of freshwater are truly a global problem, particularly felt today in the dryland regions but it will be felt tomorrow worldwide. At the present time, 76% of the world’s population has a specific water availability of less than 5,000 m3 per year per capita and 35% of that figure has very low, or catastrophically low water, supplies. This situation will deteriorate further in the beginning of the new century — by 2025 most of the Earth’s population will be living under the conditions of low or catastrophically low water supplies, at 1000 m3 per year per capita.1
How much water is available?
Less than 3% of the world’s water is freshwater.
A new appraisal shows that of the total 1386 million km3 of water (Earth’s hydrosphere)2:
- 97.5% is saltwater, e.g., oceans, seas
- 2.5% is freshwater (54.65 million km3)
Freshwater comes from different sources:
- The greater portion of the freshwater (68.7%: 37.4 million km3) is in the form of permanent ice (Arctic, Antarctic, alpine mountain ranges, etc.)
- 29.9 % of the freshwater (16.24 million km3) is ground water, mostly deep seated
- Only 0.26% (or, 64,000 km3)of the total freshwater is in lakes, river systems, etc. and it is accessible for our needs. In fact, the total water withdrawals worldwide is less than 5000 km3 or about one tenth of the total river discharge — a mere drop of Earth’s waters.2
How can we address freshwater shortages?
The world consumes too much freshwater.
The gap between withdrawal (5,000 km3) and availability (64,000 km3) is the subject of schemes to address water shortage, river control and the like. National and international institutions are capable of designing and implementing such schemes to increase our very limited share of freshwater. Regional and intra-basin consultations, negotiations, conventions, and agreements all move within the space between withdrawal and possibly available. This possibly available is nearly 0.1% of global freshwater.
We need to extend the scope of our ambition so as to take a less austere bite of the millions of cubic kilometers of global waters. To do this, three areas of technological advancement need to be addressed with a view to make the tapping of additional portions of water economically acceptable. We must develop:
Desalination, or removal of salt from water, is a viable solution to freshwater shortages.
Technologies for desalination of salt and brackish water. At present, there are technologies to provide freshwater for municipal use, especially in coastal areas. But we need technological breakthroughs, including non-conventional sources of energy, that would make the cost of desalinated water acceptable for agriculture and industry. For example, present desalination technologies do not allow the use of desalinated water in agriculture, so there is a need to explore options to make the water economically usable.
Development of pumping technologies for hauling deeply seated groundwater that would make it cost-effective for use in agriculture and industry.3
Freshwater technology must be a global initiative.
40% of land is arid (without freshwater).
Conclusion: A global water facility would reduce the amount of arid land and, in the process, global warming.
- Development of means for transporting (towing) bodies of ice from northern and southern oceans to territories of water deficit.
A world facility, supported by an international centre for water technologies or an international programme with a network of regional centres, needs to be established. This facility must be provided with means and with generous resources that will enable it to deliver the required results.
The first step is for the international community to recognize water shortage as a global issue. The shortage is clearly evident today in arid zones of the world (some 40% of the land) and will, during the next century, be evident worldwide. If additional freshwater resources were available today, we would be able to:
- expand food-producing land, thus ensuring food security for some 3 billion people who lack this security.4
- expand the global sinks for greenhouse gases and thus delay the threat of global warming, a pending hazard in the second half of the next century.
Editor’s Note (11/02): According to 2002 USA data and estimates, the cost for desalinated water in coastal areas varies. One factor for lowering costs is to build a desalination facility next to a power plant, allowing it to share water intake and discharge pipes. For example, Tampa Bay Water’s desalinated water facility in Florida, to be launched in January 2003, will be the world’s cheapest at $1.88 per thousand gallons because of its proximity to a power plant. The cost in Tampa for traditional fresh water supplies now ranges from $1.50 to $1.75 per thousand gallons. In contrast, Marin County’s proposed facility in California would supply desalinated water at a higher cost, $5 per thousand gallons, because the county has no power plants. The estimated cost for desalinated water in some other coastal areas in California ranges from $2.63 to $3.37 per thousand gallons. (Source: Marin County Water District, Tampa Bay Water, and International Desalination Association in USA Today, 10/22/02.)
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International Water Facility
Safeguarding our water
An article in Scientific American (2001) provides a good summary of freshwater supply problems and examines the pros and cons of various solutions.
Population Reports “Solutions for a Water-Short World”
This publication provides a comprehensive discussion of water supply issues as they relate to the world’s increasing population. Seven chapters of information, including figures and tables, include highlights such as “how is water used?” and “water-short countries growing.”
Water conservation portal and search engine.
Global Environment Outlook 3
The UN Environment Programme released this major report in May 2002. The report collated the thoughts of more than 1,000 contributors to assess the environmental impact of the last 30 years and outline policy ideas for the next three decades. It concluded that without action, the world may experience severe environmental problems within 30 years. The entire report can be read online (or purchased) and “Chapter 2: Freshwater” focuses on potential drinking water shortages.
This site is “dedicated to providing up-to-date water information, data, and web connections to organizations, institutions, and individuals working on a wide range of global freshwater problems and solutions.”
Everything you want to know about fresh water in an easy-to-read format, from Environment Canada. The second link shows you the many steps you can take to help clean the air, save energy, conserve water and prevent pollution.
Desertification of Arid Lands
This in-depth report (1986) covers the history, extent, and magnitude of desertification in Africa, Asia, Australia, and North and South America.
Give Water A Hand
Program for youth groups or classes to help kids take action to improve local water quality. Young people team up with educators, natural resource experts, and committed community members to study water issues and take action.
Water Saver Home
The site describes itself as a virtual encyclopedia of water saving tips particularly useful if there is a drought affecting customers in your local service area. This website was developed for home residents anywhere in the nation by the California Urban Water Conservation Council.
The Groundwater Foundation
This nonprofit organization is “dedicated to educating and motivating people to care for and about groundwater.” Check out the community service project ideas, learn how to organize a water festival or educational summer camp, and get lots of tips on groundwater protection.
Water: Use it wisely
Water saving tips, 100 ways to save water, and links to your local conservationist.
Become a FIELD partner
Financial Information Engine on Land Degradation (FIELD) collects information to help combat global desertification. FIELD-partners (organizations, professional groups, or countries) can help “by providing information, thematic expertise, technical collaboration, and/or co-funding.”
nhà cái tặng tiền cược miễn phí tháng www.ailanigardens.com original lesson
This lesson has been written by a science educator to specifically accompany the above article. It includes article content and extension questions, as well as activity handouts for different grade levels.
Lesson Title: Water Everywhere: Is There Enough to Drink?
Levels: high school - undergraduate
Summary: This lesson focuses on water supply issues stemming from population growth and land use. Students can complete histograms on global water usage, create a water usage trivia game or campaign, write a “sinkhole” news article, examine an aquifer system, illustrate a desalination process… and more!
(To open the lesson’s PDF file, you need Adobe Acrobat Reader free software.)
Useful links for educators
The following link will take you to lessons and resources available on other web sites:
- » This educational kit on desertification is suitable for early middle school.
It includes a teacher’s guide, a set of case studies, two cartoons and a
wall poster. Languages: English, French, Spanish.
- » Water-related Curricula
Website with 160 different water-related curricula on all topics ranging
from ecosystems to sources of pollution to protection and the role of
government. All age groups.
- » USGS Activity Center
Online activities where students can fill out a form to estimate how much water their family uses at home on an average day, express their views about water shortages in a survey, or work on a fun quiz. The second link takes you to the water cycle site, with a useful diagram in several languages.
- » UK’s Severn Trent Water
The world’s fourth largest privately-owned water company offers classroom activities. Included are downloadable teacher’s guides and student activity sheets. Click on “Teachers Resources.”
- » Educating Young People about Water - PreK-12
Guides and water curricula database that assist in developing a community-based, youth water education program.
- » National Ground Water Association’s K-12 Educator Resources
An online directory of lesson plans, classroom materials, teacher workshops and training, and reference tools related to ground water.
- » Water Sourcebook Units Grades K-2, 3-5, 9-12
” Activities teach youth through experimental learning methods the importance of preserving and enhancing water resources.” Spanish version can be ordered online.
- » Conservation and Biodiversity
A hypertext Book by Peter J. Bryant, School of Biological Sciences, University of California, Irvine, examines the origin, nature and value of biological diversity, the threats to its continued existence, and approaches to preserving what is left.
Useful links for student research
In addition to the links in the “learn more” section above:
- » Water Science Glossary
Definitions of terms and measurements related to water science.
- » Population Statistics
World population statistics estimates, searchable by country.
- » Water Statistics
The WorldWatch Institute provides tables and information about the world’s freshwater resources. Included is information about desalination capacity for select countries. Click on “water data” on the home page.
- » Global Rivers Environmental Education Network (GREEN)
Activities, links, and information about watersheds and youth involvement in their protection. Categories include watershed basics, water quality monitoring, and conducting research.
- World Water Resources: A New Appraisal and Assessment for the 21st Century. UNESCO, 1998.
- Peer-Reviewer’s note: Most places in the world are already over-drafting ground water resources. For example, the U.S. removes 25% more water than its recharge rate and in Beijing, China, water withdrawal from ground water is resulting in a decline of levels from one to three meters per year.
- Peer-Reviewer’s note: At February 2001 rates, it would cost a minimum of $10,000 to obtain desalinated water from nearby salt water to irrigate a commercial cornfield. The cost becomes staggering when you must haul it long distances.
- World Health Report 2000, World Health Organization.