Human life depends on a tiny fraction of the world’s water, which is constantly recycled between the oceans, land and atmosphere. Freshwater reserves are unevenly distributed, which creates water-rich and water-poor regions (in which shortages occur). Millions lack access to both safe drinking water and improved sanitation facilities and are affected by water-borne diseases as a result. Improving water quality and sanitation for the poorest requires sustainable development that uses appropriate technology and the expertise of local communities. Diseases contracted from contaminated water such as malaria and cholera are being effectively controlled in many areas. Water pollution such as marine oil slicks is a worldwide environmental issue and many countries have responded by introducing laws and agreeing to international conventions to prevent it.
CONTENTS a) Global water distribution
h) Managing pollution of fresh water
b) The water cycle
i) Managing water-related disease
c) Water supply
j) Case study: Environmental impacts of the Three Gorges Dam
d) Water usage e) Water quality and availability f) Multipurpose dam projects
k) Case study: Cleaning up the River Rhine
g) Causes and impacts of water pollution
LEARNING OBJECTIVES Describe the distribution of the Earth’s water. Describe and interpret the water cycle. Describe the sources of fresh water used by people. Describe the different ways fresh water can be used. Compare the availability of safe drinking water (potable water) in different parts of the world. Describe and evaluate multipurpose dam projects. Describe the sources of water pollution.
Describe and explain the impact of pollution of fresh water on people and on the environment. Describe and explain strategies for improving water quality. Describe the life cycle of the malaria parasite. Describe and evaluate strategies to control malaria. Describe strategies to control cholera. Describe the impact of a named multipurpose dam scheme. Describe the causes, impact and management of pollution in a named body of water.