What is “virtual” or “hidden” water?

Virtual water, sometimes known as “embedded” water, is a measure of the amount of “invisible” water required to generate various foodstuffs and products. Many products require a considerable amount more water to create than might be suggested by looking at it. For example, a cup of coffe requires around around 140 litres of water and a cotton T-shirt needs around 2000 litres! This water is needed to grow, wash and process the products and refers to any water required during the product cycle.

You can discover more about the idea of virtual water here: http://news.bbc.co.uk/1/hi/sci/tech/8628832.stm

This is an increasing problem as many countries are effectively “exporting” large quantities of water in products they generate. This is occurring in many parts of the developing world where growing demand for water from increasing populations  and “thirsty” technology is combining with a decline in available water due to previous consumption of reserves, poor management and changing climatic condition.

You can listen to Prof Tony Allan of King’s College London (http://www.kcl.ac.uk/schools/sspp/geography/people/acad/allan/research.html), who developed the concept, talking about the idea here:

http://podcast.ulcc.ac.uk/accounts/kings/Geography_Tony_Allan/Tony_Allan.mp3

From a sustainable development point of view, this metrication of water required to generate the goods and services we consume allows us to create a “water footprint” which shows the impact of individuals, groups and activities on our water supply. You can find more about this here: http://www.waterfootprint.org/?page=files/home

What effect has drought had on people and the environment in Kenya?

Kenya’s ongoing drought is having a severe effect on the environment, causing a number of changes as lakes dry up and plants and trees suffer. The drought combines with other man made pressures on the ecosystems and has a knock on effect on the people who rely on those environments to sustain them:

http://news.bbc.co.uk/1/hi/world/africa/8267165.stm

http://www.nytimes.com/2009/09/08/world/africa/08kenya.html?_r=1

http://news.bbc.co.uk/1/hi/world/africa/8057316.stm

There are concerns that problems caused by the drought may ignite tribal violence:

http://www.abc.net.au/news/stories/2009/09/21/2692148.htm

One of the main ecosystems under threat is the Mau Forest. This report from the United Nations Environment Programme (UNEP) explains some of the treats facing the Mau forest; a list to which drought can be added:

http://www.unep.org/dewa/assessments/EcoSystems/land/mountain/MauCrisis/index.asp

Kenya Forests works to find a sustainable future for Kenya’s forest resources:

http://www.kenyaforests.org/

Are we running out of water?

Everyone needs water to live and it’s in increasing demand for industrial processes, recreation and agriculture. The World’s increasing population and the variation in the distribution of water that is occurring due to climate change are additional factors which must be managed.

This map shows where water stress is expected to occur:

http://news.bbc.co.uk/1/hi/sci/tech/7821082.stm

Some experts expect there to be a “scramble for water” as sources dry up in some areas:

http://news.bbc.co.uk/1/hi/business/7790711.stm

Many people think that there needs to be a global discussion about how water resources can be allocated more fairly:

http://news.bbc.co.uk/1/hi/business/7773298.stm

How does the Central Arizona Project provide water for desert cities?

Cities such a Tucson and Phoenix in Arizona, USA, would not be able to survive without bringing water in from elsewhere. The Central Arizona Project (CAP) is how they do it. What issues does this raise for the future of water management in dry areas?

http://en.wikipedia.org/wiki/Central_Arizona_Project_Aqueduct

http://www.cap-az.com/

Water related conflicts: will they be more common in the future?

When water supplies come under stress through over use or rain shortages, conflict is often not far behind, as this example from Ethiopia shows:

http://news.bbc.co.uk/1/hi/world/africa/7929104.stm

How is drought affecting the cattle farmers of Argentina?

Argentinian beef is world famous, but in 2009 a drought hit the indutry hard. Find out how farmers coped and what the future might bring for them:

http://news.bbc.co.uk/1/hi/world/americas/7905357.stm

Why do poorer people pay more for water?

The installation of advanced water infrastructure in more economically developed countries (MEDCs) means that water is often cheaper there than in LEDCs, where there are more labour costs involved. In some places, particularly urban areas, buying water takes up a large part of a family’s budget:

http://news.bbc.co.uk/1/hi/sci/tech/7867202.stm

How will the USA cope with reduced water supplies from the Colorado river?

The Colorado is one of the world’s most important rivers, providing water for much of the southwestern USA, but it is predicted that it will not be able to meet growing demands in the future, so can it be managed sustainably to meet those needs?

http://news.bbc.co.uk/1/hi/world/americas/7829850.stm

How has DFID helped the people of Bangladesh escape hazards associated withe river flooding?

Bangladesh id a relatively low-lying developing nation. As well as suffering from coastal flooding, much of the land is at risk from river flooding, which also brings much-needed nutrients in the form of river sediment.

You can find the overall development plan for Bangladesh from 2007 to 2009 here:

http://www.dfid.gov.uk/pubs/files/BICAPfina20070903public.pdf

Ond DFID backed project is helping people who live on islands or “chars” in the Ganges-Brahmaputra River:

http://www.clp-bangladesh.org/

This has helped deal people cope with floods such as those in 2007:

http://www.dfid.gov.uk/news/files/floods.asp

What is the Hjulstrom Curve all about?

The Hjulstrom Curve is a very useful tool in the study of rivers. It shows what size material will be entrained (picked up), transported and deposited at different velocities.

Whilst you might expect the smallest particles to require the least energy to pick up, this is not always true, as the smallest particles often carry a charge, which allows them to flocculate (stick together). This means that they actually require higher velocities to be entrained than particles which are slightly bigger.