THEMATIC SLIDES
WATER AND LAKES
WATER AND LAKES
• Lake Chad, Nigeria, Niger, Chad, Cameroon
• Challawa Gorge Dam, Nigeria
• Lake Nakuru, Kenya
• Lake Victoria, Uganda
• Lesotho Highlands Water
Project, Lesotho
• Aral Sea, Kazakhstan
• Lake Balkhash, Kazakhstan
• Kara- Bogaz -Gol (KBG), Turkmenistan
Estimated global
water loss in
irrigation
Source: FAO
WATER AND LAKES
• Dead Sea, Jordan
• Lake Hamoun, Iran
• Mesopotamia Marshlands, Iraq
• Three Gorges Dam, China
• Atatürk Dam, Turkey
• Gabcikova, Slovakia
• Lake Chapala, Mexico
• Everglades, United States
Three Gorges Dam, October 24, 2003: Digital Globe
WATER FACTS
• Of total world water, 97.5% is salty water and only 2.5% is
freshwater of which useable freshwater accounts for about 0.5%
• Of the 0.5% useable freshwater, irrigation accounts for 70%, industry
20% and household 10%
• Demand for and use of freshwater has tripled over the past half
century, as world population has grown from 2.5 to 6.45 billion people
• Experts predict that by 2025 global water needs will increase with 40%
more required for cities and 20% for growing crops
• The satellite photos show major freshwater depletion taking place on all
continents, notably in the Dead Sea, the Aral Sea, Lake Chad, the
Mesopotamian Marshlands, the Everglades and other water sources
• According to UNESCO estimates, by 2030 global demands for fresh
water will exceed the supply with potentially disastrous consequences
Sources: Asian Development Bank; BBC; Earth Observatory; UNEP; UNESCO
WATER FACTS
• Water withdrawals are causing major rivers—such as the Colorado, the
Nile, the Yellow Rivers—to run dry, lakes to vanish and groundwater
tables and aquifers to drop almost everywhere
• Over the next 20 years, average water supply per person is estimated
to drop by a third, endangering human health, agriculture and the
environment
• Water volume in the Aral sea has dropped by about 80% since 1960s,
due to extensive irrigation primarily for cotton production
• Current water levels in Lake Victoria are below normal and the lowest
level since September 1961
• In 2002, around 3.16 billion people (82%) in the Asia Pacific region had
access to improved water supplies, up from 74% in 1990
• Water pollution is a serious threat to the world’s water supply
Sources: Asian Development Bank; BBC; Earth Observatory; UNEP; UNESCO
Shrinking Lake Chad
Nigeria, Niger, Chad, Cameroon
Persistent drought has
shrunk the lake to about
a tenth of its former size
• 1972: Larger lake surface
area is visible in this image
• 2001: Impact of drought
displays a shrunken lake,
comparatively much smaller
surface area than in 1972
image
Impact of Challawa Gorge Dam, Nigeria
These images show the
area before and after
construction of the dam.
• 1990: Image of the area
before the completion of
the dam in 1993
• 1999: Impact of flooding
upstream from the dam;
colour of the water in the
flooded area indicates high
sediments
Land cover degradation around
Lake Nakuru, Kenya
These images show the
land cover degradation in
the lake’s catchment
• 1973: The area that hosts
the world’s largest
concentration of flamingos
• 2000: Excision of forest in
the Eastern Mau Forest
Reserve (white lines) will
most likely lead to
disappearance of upper
catchment forest cover
Water hyacinth in Lake Victoria
Uganda
These images show
water hyacinth infestation
and control of such
invasive species
• 1995: Image shows several
water-hyacinth-choked bays
(yellow arrows)
• 2001: A visible reduction of
Water Hyacinth, after its
removal from Lake Victoria,
contributes to human
prosperity
Population growth around Lake Victoria
Uganda
• The population growth
around 100 km buffer zone
of the Lake Victoria
• Population growth around
Lake Victoria, East Africa, is
the highest in Africa
Fastest growing rural population
around Lake Victoria, Uganda
50.00
Total Human Population Living around Lake Victoria
(millions)
47.23
41.80
40.00
30.51
30.00
22.13
20.00
16.05
11.71
10.00
8.57
0.00
1960
1970
1980
1990
2000
Total Population
2010
2015
Lake Victoria vs. Africa
246
250
218
200
159
150
115
100
84
61
50
45
9
12
16
21
26
32
36
0
1960
1970
1980
Lake Victoria
1990
2000
2010
Africa Average
2015
TitleHeight variation of Lake Victoria, Uganda
Body text
Lake Victoria Height Variations
http://www.pecad.fas.usda.gov/cropexplorer/global_reservoir/gr_regional_chart.cfm?regionid=eafrica&region=&reservoir_name=Victoria
Title
Monitoring Lake Victoria, Uganda
Body text
Current water
levels are
below normal
and the lowest
level since
September,
1961
Changes due to dam construction in Lesotho
Lesotho
The Lesotho Highlands
Water Project diverts
water for South Africa’s
urban and industrial use
• 1989: Image of the area
before the completion of
the dam in 1995
• 2001: Katse dam created
an enormous reservoir, the
extent of which can clearly
be seen in this image
Death of a sea - Aral Sea, Kazakhstan
Images show death of the
world’s fourth largest inland
sea
• 1973: The surface of the
sea once measured 66 100
km2
• 1987: 60% of the volume
had been lost
• 1999-2004: The sea is
now quarter of the size it
was 50 years ago
Alarming drop in Lake Balkhash’s water level
Kazakhstan
• 1975-1979:
Excessive use and
waste of lake water are
causes of the drop
• 2001: Smaller
neighbouring lakes
appear to be drying up
Kara-Bogaz-Gol – Lagoon of the Caspian sea
Turkmenistan
Caspian Sea is the largest
inland body of water in the
world
• 1988: KBG is the large
shallow lagoon of the
Caspian sea
• 2000: Caspian Sea levels
are higher than 1978 levels
and water flows freely into
salty waters of KBG
Dramatic changes in Dead Sea, Jordan
Images show dramatic
changes in the Dead
sea over 30 years
• 1973: The Sea
level is dropping at
the rate of 1m/year
• 2002: Notice the
expansion of salt works,
and near-complete closing
off of the southern part by
dry land
Changes in water levels on Lake Hamoun
Iran
Changes in water
levels on Lake
Hamoun
• 1976: The amount of
water in the lake is
relatively high
• 1999-2001: The
lake dried up and
disappeared
Demise of an ecosystem – Mesopotamian
Marshlands, Iraq
• 1973-2000: Most of the
wetlands disappeared
Upstream damming as well
as drainage activities in the
marshlands themselves
have significantly reduced
the quantity of water
entering the marshes
Restoration of the Mesopotamia Marshlands
in Iraq
• 2000: Water returns
to the Mesopotamian
Marshlands
• 2004: Greening of
some of the
Marshlands in recent
years
Changes due to Three Gorges Dam
construction, China
Changes due to the
construction of dam
• 1987: Nature of the river
and surrounding landscape
before the dam
• 2004: The
enormous dam is
clearly visible
Changes due to Atatürk Dam, Turkey
Development of
Harran region is
strikingly apparent in
these images
Right-hand corner of
the 1999 image
shows irrigated
fields surrounding
the town of Harran
The dam provides
power and irrigation
water
Damming around Gabcikova, Slovakia
1973-2000:
Images show
changes brought
about by massive
re-channeling of
river water
Country’s largest natural lake - Lake Chapala
Mexico
• 1983: Level of the lake
has declined; noticeable
decreases in wetlands
• 2001: Alteration in
the contours of the
shoreline is clearly
visible
Urban encroachment in Florida’s Everglades
United States
• 1973: Rapid urban
expansion has
converted farmlands
to cityscapes
• 2002: Existence of
vast wetlands
“Everglades”
threatened by urban
encroachment
WATER AND LAKES
•
•
•
•
•
•
•
•
•
•
•
Lake Kivu, Congo/Rwanda
Lake Alaotra, Madagascar
Lake Al Wahda, Morocco
Lake Cahora Basa,
Mozambique
Lake Chivero, Zimbabwe
Lake Djoudj, Senegal
Lake Ichkeul, Tunisia
Lake Manantali, Mali
Lake Sibaya, South Africa
Songor Lagoon, Ghana
Lake Tonga, Algeria
LAKE FACTS
• According to the WORLDLAKE database, there are 677 lakes in
Africa
• There are 15 natural lakes that cross the political boundaries of two or
more countries in Africa
• There are 60 transboundary river basins in Africa, covering over 63
per cent of the continent’s land area
• Lake Chad’s surface area has shrunk by 95 per cent over the past 35
years
• Uncontrolled damming, the withdrawal of water for irrigation, and
climate variability are the major causes of drying up of Lake Tonga in
Algeria
• Population growth around Lake Victoria, the continent’s largest
lake, is significantly higher than the rest of Africa
• Some lakes in central Africa have become known as “killer lakes,”
because of the catastrophic natural events that have occurred in
their vicinity
Sources: UNEP 2006
Lake Kivu-one of Africa’s “killer lakes”
Congo/Rwanda
These images show
dramatic changes before
and after the eruption of
Mt. Nyiragongo in 2002
• 2001: Before the January
2002 eruption
• 2003: Shows the track of
the lava flow
Severe flooding around Lake Alaotra
Madagascar
These images show
flooding over a wide area
• Flooding destroys
significant portion of crops
• Intensive rice irrigation
occurs at the western part
of the lake (yellow arrows)
Impact of Al Wahda reservoir in
Morocco
These images illustrate
the change in land cover
• 1987: The area before
the construction of dams
• 2001: The area after the
construction of 110 large
dams
Cahora Basa – Mozambique’s
largest dam on the Zambezi River
These images show
spectacular changes in the
Zambezi riverine system
• 1972: The Zambezi River
a few years before the dam
construction
• 1999: This image shows
part of the enormous dam
and the lake
Invasive water weeds in
Lake Chivero, Zimbabwe
These images show
overall reduction in water
weeds
• 1989: Weeds show up as
green strands along the
edges of the lake
• 2000: This image shows
that water weeds remains a
persistent problem
Rejuvenation of the Djoudj
Sanctuary in Senegal
These images show the
Djoudj Sanctuary before
and after the construction
of the Diama Dam
• 1979: Shows the impact
of drought on the Djoudj
Sanctuary
• 1999: Rejuvenation of the
Sanctuary wetlands due to
significant floods
Ecological changes around
Lake Ichkeul, Tunisia
These images show the
impact of damming
• 1972: Shows the three
feeder rivers supplying the
lake before they were
dammed
• 2000: Shows the location
of the dams (yellow arrows)
Agricultural expansion around
Lake Manantali, Mali
These images show the
expansion of irrigated
agriculture
• 1977: Shows the original
meandering nature of the
Bafing River
• 1999: Shows the
expanded irrigated land and
increase in lake water
quantity
Lake Sibaya – wetland of international
important in South Africa
These images show
increase in cultivation
around the lake
• 1991: Lakeshore is home
to the only known species
of a rare climbing orchid
• 2001: The yellow arrows
vividly show the increase
of cultivation of marginal
lands around the lake
Reduction in the surface area of
Songor Lagoon, Ghana
These images show a
conspicuous reduction in
the surface area
• 1990: Shows major
lagoon system associated
with Volta river estuary
• 2000: This image shows
water area dramatically
reduced, exposing bare
ground
Changes in and around Lake Tonga
Algeria
These images show the
changes brought about
by damming of the
feeder rivers
• 1988: Lake Tonga before
the damming of feeder
rivers
• 2000: Damming
increased irrigation and
drastically reduced the
volume of water entering
the lake
WATER
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