The challenge of resource management (box 8)

Question 1

Sustainable water strategies..

Answer 1

-Water conservation, groundwater management, recycling and ‘grey water’

Question 2

What is water conservation + 4 examples

Answer 2

• involves using water more sparingly and reducing waste
• Reducing water usage by installing water meters in homes and businesses.
• Using more efficient irrigation techniques such as drip irrigation rather than using sprinklers, which lead to greater rates of evaporation.
• Reducing leakages caused by broken pipes. Up to one-third of the global water supply is lost due to leaks. 3.3 billion litres of water is lost every year in the UK.
• Preventing water pollution of aquifers and rivers, therefore conserving freshwater supplies.

Question 3

Ground management- how are aquifers needed to be sustainable

Answer 3

• Abstracting water from aquifers needs to be balanced by natural recharge (precipitation) or artificial recharge (pumping water into an aquifer) from rivers and lakes

Question 4

What is ‘grey water’

Answer 4

-waste domestic water. It is increasingly being recycled and used both inside and outside the home

Question 5

What is a sand dam?

Answer 5

• a simple, low cost way of trapping water without it evaporating in a hot dry climate
• A low reinforced concrete wall (dam) is built across a section of a seasonal river

Question 6

How does a sand dam work?

Answer 6

• During the rainy season flood water and sand build up behind the dam as the coarse material becomes trapped
• The wet sand contains water in-between the pore spaces/holes in the sand which is stored until a well is dug down into the sand during the dry season

Question 7

Why are sand dams sustainable?

Answer 7

• The advantage is that the water table is raised and vegetation around the river is also sustained.
• The dam is a good example of appropriate technology, as it is low cost, has no operational costs and requires very little maintenance.
• The dam is socially sustainable as it uses locally sourced materials and encourages community co-operation as they are community owned and managed.
• The height of the dam can be increased year on year to store more water if needed. Alternatively, a series of small dams can be built along one river. This means the method can be adapted to the situation.

Question 8

Sand dam case study example

Answer 8

• An NGO, The Water Project has worked with the Africa Sand Dam Foundation to construct a sand dam in Mukimwani village (population: 5200), located approximately 100km southeast of the capital, Nairobi
• many villagers had to travel 3-4 kilometres to fetch water – typically people spent 2-3 hours per day