From last lesson….
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Name 2+ countries/areas of the world with:
Little or no water scarcity
Physical water scarcity
Approaching physical water scarcity
Economic water scarcity
Learning Objectives
• To understand further how humans can impact
on water availability
• To understand how three areas’ water supplies
have been affected by humans
a)Citarum, West Java, Indonesia
b) China
c) the Murray – Darling Basin, Australia)
Sewage disposal
• By 2020 sewage disposal in developing
countries is expected to cause 135 million
deaths
• Diseases such as typhoid and cholera are
common
• Example = in the UK they add 1,400 million
litres of sewage to their rivers daily
• Example = Citarum River, West Java. Carries
the waste from 9 million people
Sewage disposal
Citarum River Indonesia
http://www.youtube.com/watch?v=NKfSoMyz
zME&feature=fvw
http://www.youtube.com/watch?v=4IJa7S_
pVSQ
Chemical Fertilisers
• This can contaminate groundwater as well as
river supplies
• Sewage and fertilisers add nutrients to the
river, increase the growth of algae and cause
eutrophication
• Example = Yucatan, Mexico high levels of
nitrates in groundwater
• Example = Gulf of Mexico, high levels of algae
Chemical fertilisers
http://www.youtube.com/watch?v=29mtxC
C_fao
Industrial Pollution
• 400 billion tonnes of industrial waste is
generated each year in the world
• Much such as chemicals and heavy metals are
put into the water
• Examples in NE China
• Example = Citarum River in West Java,
Indonesia, carriers the waste from hundreds
of farms and factories.
Industrial Pollution
http://www.youtube.com/watch?v=fl7
xR5MLvIY
Dams
Dams
• These trap sediment
• These reduce the floodplain fertility
• These reduce the flow of nutrients from the river
to the sea
• These damage coastal fish stocks
• The sediment change can kill fish and impact on
the ecosystem
• Example = Aswan Dam on the River Nile
• Example = 3 Gorges Dam, China ( see notes on
blog)
The Three Gorges Dam, China (for flood protection AND HEP)
• In 1998 3000 deaths and 30 million people homeless from Yangtze flood
• Dam built at Sandouping (to be totally finished in 2012 but already functioning)
• Advantages (Economic, social and environmental)
• 100 million people downriver protected as water dischrged through dam when necessary
• HEP needed for China's growing industry and for domestic use too (China uses 40% world power)
• It will provide for 2% of China's energy needs
• Tourism increased on lake
• Improved shipping as larger cargo boats (up to 10,000 tonnes) can travel upstream to Chongqing
• New settlements have better services eg water, sewage etc
• Disadvantages (Economic, social and environmental)
• 1.3 million people relocated often without adequate compensation
• 4 cities, 8 towns and 356 villages submerged
• Temples and sacred places flooded
• Factories submerged releasing toxic waste into water
• Silt builds up behind dam so does not fertilise fields downstream
• Risk of earthquakes cracking dam and causing flooding
• 27 billion pounds to build it
• Loss of species like the Yangtze river dolphin
The Aswan Dam
Aswan is a city on the Nile in Egypt.
Two dams on the river: the Aswan High Dam and Aswan Low Dam (6km apart) with Lake
Nasser behind.
Benefits of dam construction
Without the 3,600m dam the Nile would flood each year during summer so dam needed to
protect farmland and cotton fields. Dam stopped major floods in 1964 and 1973.
Provides water for agriculture to stop widespread drought and famine.
Generates energy - hydroelectric output of 2.1 gigawatts - produced around half of Egypt's
entire electricity production in the 1960s.
A new fishing industry has been created around Lake Nasser.
Problems of dam construction
Dam construction flooded much of lower Nubia
Over 90,000 people lost their homes.
Lake Nasser flooded valuable archeological sites.
The silt which was deposited in the yearly floods, and made the Nile floodplain fertile, is now
held behind the dam.
Silt deposited in the reservoir is lowering the water storage capacity of Lake Nasser.
Poor irrigation practices are waterlogging soils and bringing salt to the surface (salination).
Mediterranean fishing declined after the dam was finished because nutrients that used to flow
down the Nile to the Mediterranean were trapped behind the dam.
The red-brick construction industry, which used delta mud, is also severely affected.
Significant erosion of coastlines (due to lack of sand, which was once brought by the Nile) all
along the eastern Mediterranean.
Over abstraction of Water
• Can be removed for irrigation or drinking water
• If too much is removed, in arid areas the water
can not return
• Example of over extraction = Bangladesh and
Pakistan
• Over abstraction can also led to salt water
incursion and salinisation. Can occur in wells, or
on the coast (See P65 Oxford)
• Example = California coastline
Why does this NIC have water
scarcity? P88-89 Oxford
Task –MEDC example of Murray Darling Basin, Australia
P82-87 Oxford
• Use the Oxford book and supplement your notes
with this case study. Make sure you cover :
• Salinity
• Eutrophication
• Groundwater
Put in Specific
• Soil degradation
Place detail
• Impacts on ecosystems
• Cultural Impacts
Is it always cheaper to get water in
the poorer nations?
And are water bills similar
throughout a country?
Average monthly bill for a family of four in USA…
The Price of Water 2012:
18 Percent Rise Since
2010, 7 Percent since 2011
in 30 Major U.S. Cities