Resource 2: Water issues

Background information / subject knowledge for teacher

Adapted from: Operation Blessing, International

Water pollution

Pollution is caused by:

  • sewage and fertilisers;
  • silt and other sediments (deposited rocks that build up in layers);
  • organic material such as leaves and grass clippings.

Water consumption and use

Global water consumption rose sixfold between 1900 and 1995 – more than double the rate of population growth – and goes on growing as farming, industry and domestic demand all increase. 70% of the water used worldwide is used for agriculture. Much more will be needed if we are to feed the world’s growing population – predicted to rise from about 6 billion today to 8.9 billion by 2050.

It is not just us who need water, but every other species that shares the planet with us – as well all the ecosystems on which we, and they, rely.


More than five million people die from waterborne diseases each year – ten times the number killed in wars around the globe.

Climate change

Climate change will also have an impact. Some areas will probably benefit from increased rainfall, but others are likely to be losers. We have to rethink how much water we really need if we are to learn how to share the Earth’s supply. While dams and other large-scale schemes play a big role worldwide, there is also a growing recognition of the value of using the water we already have more efficiently rather than harvesting ever more from our rivers and aquifers. For millions of people around the world, getting it right is a matter of life and death.

Resource 1: Plant handout

Resource 3: Maize seed experiment