Water Supply Flashcards
How is Water Used?
Agriculture is by far the World’s biggest user of water. Water is used for animals, but the
majority is used for irrigation.
The amount being used by agriculture is also increasing as the World’s population increases and the demand for food increases.
Household or domestic use in the next biggest user.
The most water is usually used in toilets, but also washing machines and shower/baths use significant percentages.
Industry and energy production also uses large percentages in manufacturing and cooling processes.
The fourth biggest user is actually water lost through evaporation and leaks in reservoirs.
Differences in water use
In general, developing countries such as Bangladesh will use most of their water in agriculture (farming) and little in industry or domestic use.
Farming is a large part of Bangladesh’s economy so a large percentage of its water is used for that purpose.
Developed countries such as the UK have a more significant use of water for domestic reasons.
Developed countries also tend to have a higher percentage for industrial use.
Strategies to increase water supply
Dams and reservoirs
Water transfers
Desalination plants
Dams and resorviors
Rivers transport water to the sea. Dams block rivers so that reservoirs of water build up behind, rather than drain away. This provides large supplies of drinking water all year round and reduces water insecurity, especially where precipitation may be seasonal. Dams and reservoirs can also prevent flooding, as the flow of the river is controlled, and they can generate electricity through hydroelectric power (HEP). There over 600 dams in Africa. The Akosombo dam in Ghana and the Aswan dam in Egypt are two of the largest.
Water transfers
When a country has a water surplus in one area and a water shortage in another, supplies can be transferred.
This is called a water transfer scheme. Reservoirs collect and store water in areas of high rainfall. Canals and pipes transport the water to rivers or reservoirs in other parts of the country.
Water transfer schemes can be found in lots of different countries.
The city of Las Vegas is able to exist in the Nevada Desert because water is transferred to it.
Desalination plant
It is not possible to drink seawater as it contains salt.
Desalination plants remove the salt from seawater to make it safe to drink.
Desalination plants could solve many of the world’s water insecurity issues, but the process is expensive and therefore not viable in some developing countries.
The UK has opened its first desalination facilities on the river Thames.
The plant removes the salt from tidal water from the river Thames to help the UK during times of prolonged low rainfall and drought.
Economic water scarcity:
This is when water is available, but for some reason it is inaccessible or unusable.
This might because it is groundwater that is expensive to extract or that the cost of transporting it is too expensive or simply that the supply of water has become polluted.
Physical water scarcity:
This is when there is not enough water available. The most common reason for this is low precipitation rates.
Water stress:
This is when the demand for water exceeds the supply of water causing water shortages.
Water shortages are known as droughts.
Water stress basically happens when demand exceeds supply.
Below are some of the main reasons why demand is increasing and supply falling.
GROWING DEMAND for water
Population Growth:
Domestic Demand:
Agricultural Demand:
Industrial Demand:
Energy Production:
FALLING SUPPLY in water
due to
Climate Change:
Groundwater Depletion:
Pollution:
Political:
Mismanagement:
Problems Caused by Water Shortages and Water Pollution
Drought:
Crop Failure:
Famine:
Conflict:
Eutrophication:
Biodiversity Loss:
Possible Solutions to Water Shortages and Water Pollution
Irrigation Projects:
Reduced Leakage:
Dam Construction:
Water Metering:
Construction of Wells:
Conservation and Education:
In many areas in LICs, fresh water is available (for example in underground aquifers), but the issue is
accessing it.
how is this solved
Wells, dug by hand, are a common way of accessing water - but the supply can be unreliable and sometimes the well itself can be a source of disease.
Boreholes can require more equipment to dig but can be dug quickly and usually safely. They require a hand or diesel pump to bring the water to the surface.
What is a PlayPump and how does it work?
In rural Africa, clean water is a luxury. Most people don’t have plumbing in their homes. Instead, they often must walk long distances to wells and haul heavy containers of water back.
* PlayPumps international is a South African NGO (Charity) who provide PlayPumps for communities in need.
* A PlayPump is a water pump that pumps water from underground aquifers. To construct a PlayPump a borehole needs to be drilled down to an underground aquifer.
* As the merry-go-round spins, it pumps clean water up from deep underground and stores it in a huge tank. People are welcome to come and help themselves to the water.
* So far, more than 800 PlayPumps are operating in schools and communities in four African countries, providing water for almost two million people
* The PlayPump can pump up to 370 gallons (1,400 litres) of clean water an hour.
