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Current water levels in Lake Victoria are below normal an

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Title: Current water levels in Lake Victoria are below normal an


1
THEMATIC SLIDES
2
WATER AND LAKES
3
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
4
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
5
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
6
WATER FACTS
  • Water withdrawals are causing major riverssuch
    as the Colorado, the Nile, the Yellow Riversto
    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
    worlds water supply

Sources Asian Development Bank BBC Earth
Observatory UNEP UNESCO
7
Shrinking Lake ChadNigeria, 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

8
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

9
Land cover degradation around Lake Nakuru, Kenya
These images show the land cover degradation in
the lakes catchment
  • 1973 The area that hosts the worlds 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

10
Water hyacinth in Lake VictoriaUganda
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

11
Population growth around Lake VictoriaUganda
  • The population growth around 100 km buffer zone
    of the Lake Victoria
  • Population growth around Lake Victoria, East
    Africa, is the highest in Africa

12
Fastest growing rural population around Lake
Victoria, Uganda
13
Lake Victoria vs. Africa
14

Title
Height variation of Lake Victoria, Uganda
Body text
Lake Victoria Height Variations http//www.pecad.f
as.usda.gov/cropexplorer/global_reservoir/gr_regio
nal_chart.cfm?regionideafricaregionreservoir_n
ameVictoria
15

Title
Monitoring Lake Victoria, Uganda
Body text
Current water levels are below normal and the
lowest level since September, 1961
16
Changes due to dam construction in LesothoLesotho
The Lesotho Highlands Water Project diverts water
for South Africas 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

17
Death of a sea - Aral Sea, Kazakhstan
Images show death of the worlds 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

18
Alarming drop in Lake Balkhashs water
levelKazakhstan
  • 1975-1979 Excessive use and waste of lake water
    are causes of the drop
  • 2001 Smaller neighbouring lakes appear to be
    drying up

19
Kara-Bogaz-Gol Lagoon of the Caspian
seaTurkmenistan
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

20
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

21
Changes in water levels on Lake HamounIran
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

22
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
23
Restoration of the Mesopotamia Marshlands in Iraq
  • 2000 Water returns to the Mesopotamian
    Marshlands
  • 2004 Greening of some of the Marshlands in
    recent years

24
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

25
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
26
Damming around Gabcikova, Slovakia
1973-2000 Images show changes brought about by
massive re-channeling of river water
27
Countrys largest natural lake - Lake
ChapalaMexico
  • 1983 Level of the lake has declined noticeable
    decreases in wetlands
  • 2001 Alteration in the contours of the
    shoreline is clearly visible

28
Urban encroachment in Floridas EvergladesUnited
States
  • 1973 Rapid urban expansion has converted
    farmlands to cityscapes
  • 2002 Existence of vast wetlands Everglades
    threatened by urban encroachment

29
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

30
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
    continents land area
  • Lake Chads 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
    continents 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
31
Lake Kivu-one of Africas killer
lakesCongo/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

32
Severe flooding around Lake AlaotraMadagascar
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)

33
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

34
Cahora Basa Mozambiques 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

35
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

36
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

37
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)

38
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

39
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

40
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

41
Changes in and around Lake TongaAlgeria
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

42
WATER
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