Class notes 1st December: Issues of water management: Dams

The key points of today's lesson were:

• The Three Gorges Dam is being built in China.
• It is being built for four main reasons: (1) To stop flooding in the lowland areas. In 1998 floods killed thousands of people, left millions homeless and 9/10 factory workers in some areas were put out of work. (2) To provide hydroelectricity - the equivelant of 50,000,000 tonnes of coal per year. (3) As a demonstration that China is joining the 'top table' of world leading nations. (4) To make the river more navigable (to make it easier for larger ships to carry goods along the river).
• The dam itself will be the largest of its kind in the world - 185 metres high, 2km long, and creating a 600 mile long lake (reservoir) behind it.
• There are problems with the dam. 13 major cities will be flooded. 1.5 million people will have to move. Good quality farmland will be lost.

To find out more about the dam, why not visit the BBC site on it to find out the latest news. There is also a good recommended site here.

We also looked at two case studies about water management.
Case study 1 - Lesotho, in Africa. Here, water is being gathered behind large dams. Five dams are proposed in total. It is a very hilly country which recieves more rainfall than South Africa. The South Africans are buying water to provide it to Johanesburg for £35million per year.
Case study 2 - Colorado River, USA. The river flows through the desert (and the Grand Canyon!) and laws dictate who can use the water, and what they can use it for. Cities like Las Vegas require huge amounts of water. But the biggest problem is that people are using the water for irrigation (watering crops). Water is obtained by pumping it in pipes from the river. It is then placed into long canals that transport the water to the farms, where it is sprayed on the crops.