slide on akosombo dam

2. LOCATION OF AKOSOMBO DAM
• Located at
Volta river in
south-eastern
Ghana on
Volta river
Basin.

3.  Building of the Akosombo Dam takes almost a period of
two decades of planning which began in 1947.
 Actual construction took place within 1962-1972 by the
management of the Volta River Authority (VRA).
 Jointly financed by government of Ghana, the World
Bank, the United States, and the United Kingdom.
 3 phase of the project
• Phase one was installation of 588MW unit of electricity
completed in 1966.
• Phase two involved addition of 304MW electricity results
total of 912MW electricity.
• Last phase consist of setting up of a smaller hydro-electric
power(HEP) dam, 21km downstream, at Kpong.
HISTORY

4.  To make VALCO (Volta Aluminum Company) energy
sufficient so that its activity which is mainly aluminum
smelting would be proceed without interruption.
 To supply electricity for both domestic and industrial
use and also export to the basin sharing countries (Benin
and Togo).
 To provide opportunities for large-scale irrigation,
modernization of agriculture, promotion of factories and
industries, and the establishment of tourist facilities.
OBJECTIVE

5. Dam and spillways
Type of dam Embankment, rock-fill
Impounds White Volta, Black Volta, Oti River
Discharge Lower Volta River
Height (foundation) 114 m (374 ft)
Length 660 m (2,170 ft)
Width (base) 366 m (1,201 ft)
Dam volume 7,900,000 m
3
(280,000,000 cu ft)
Spillways Twin gate-controlled
Spillway capacity 34,000 m
3
/s (1,200,000 cu ft/s)
DESIGN SPECIFICATIONS

6. Reservoir
Creates Lake Volta (largest man-made lake)
Total capacity 148 km
3
(120,000,000 acre⋅ft)
Surface area 8,502 km
2
(3,283 sq mi)
Maximum length 400 km (250 mi)
Power Station
Hydraulic head 68.8 m (226 ft) (max)
Turbines 6 x 170 MW (230,000 hp) Francis-type
Penstock specifications 112-116 m long with 7.2 m diameter
Installed capacity 1,072 MW (1,392,000 hp) as per VRA
2010
DESIGN SPECIFICATIONS
(contd.)

7.  85% of all electricity generated in Ghana leads to economic
and industrial development provides by Akosombo HEP.
 Boost Ghana’s economy twice the average of the West African
sub regions.
 Volta Lake leads to increase in fishing stock.
 Farming activities is also intensified along the 5500 km
shoreline especially locations downstream of the lake.
 Navigation on the Volta river has changed significantly serving
as a mean for transportation for goods.
 The direct tourism impact resulting from the lake includes
opening up part of hitherto inaccessible attractions to both local
and international travellers.
SOCIO-ECONOMIC BENEFITS

8.  Generation of total hydro generation of 5,960GWh from
the Akosombo and Kpong Hydro Generating Stations in
the year of 2010 which is 2% greater than 2009.
 Average plant discharge in 2010 at Akosombo GS
1,201.85 cu.m/sec which is 0.5% grater than the year of
2009.
 The average unit availability attained at the Akosombo
was 96.87% above a set target of 94%.
 Ratio of gross hydro generation to firm capability of
Akosombo is132.74% in 2010.
SOCIO-ECONOMIC BENEFITS
(contd.)

9.  There has been a steady decline in agricultural productivity along
the lake and the associated tributaries.
 Downstream agricultural systems are losing soil fertility without
the periodic flooding that brought nutrients to the soil before the
natural river flow was halted by the dam.
 The land surrounding Lake Volta is not nearly as fertile as the
formerly cultivated land residing underneath the lake.
 Heavy agricultural activity has exhausted already because of
inadequate soils.
EFFECT ON ECOLOGY

10.  The growth of commercially intensive agriculture has
produced a rise in fertilizer run-off into the river leads to
eutrophication of the river waters.
 The nutrient enrichment, in combination with the low
water movement, has allowed for the invasion of aquatic
weeds which creates a formidable challenge to water
navigation and transportation.
EFFECT ON ECOLOGY (contd.)

11.  Displacement of 80,000 people across 700 villages in
low lying areas and resettle them into 52 new villages
lead to the lost of the original communities resulted in
many socio-physiological problems in the communities.
 The Volta lake creation leads to a loss of 3.6% of the
total land surface of Ghana including forest land to the
reservoir.
 As a result of less arable land to farm the men switch to
fishing while most of the women were involved in
prostitution as a profession to satisfy the male workers
whom were building the dam.
CHALLENGES ON SOCIAL
ACTIVITY

12.  For fish and other aquatic biota, due to the ability of the
dam to alter or blocking the migration resulting in
genetic disconnect between species population.
 Injustice to the communities upstream and downstream
is that it took three decades to be connected to the
national electricity grids.
CHALLENGES ON SOCIAL
ACTIVITY (contd.)

13.  The upstream and downstream communities are among the
poorest in the country lacking access to basic necessities like
hospital, roads, proper sanitation and water facilities.
 The lost land lead to decline in the primary economic
activities of crop and livestock farming for most of the
communities both downstream and upstream of the dam.
 The extensive human migration and degradation of natural
resources within the Volta-basin area, are the products of
poverty in conjunction with population pressure.
 The rural and industrial economies have experienced the
financial losses associated with the decimation of
river aquaculture.
CHALLENGES ON ECONOMIC
ACTIVITY

14.  The presence of aquatic weeds provide the necessary habitat for
black-fly, mosquitoes and snails, which are the vectors of water-
borne illnesses such as bilharzia ( 2% to 32% at downstream and
0.5% to 27.4% in upstream), river blindness and malaria
(increased by an average of 10% both upstream and downstream ).
 Children and fishermen have been especially hard hit by this rise of
disease prevalence.
 This migration enabled the contraction of HIV and has since led to
its heightened prevalence within Volta Basin communities.
IMPACT ON HUMAN WALFARE

15.  Increase in seismic activities (4 major earthquakes of
magnitude 5 or higher have been recorded in the area) around
the dam since the construction of the lake.
 Believing that earthquakes are due to the overloading of the
geological bedrock underlying the lake with which is triggering
the active Akwapim fault.
 Sediments load have decrease by about 60mg/l downstream of
the dam as a result of the impoundment.
 The lack of sediment has lead to the erosion of the coastline in
the neighbouring Togo and Benin at a rate of 10-15m/y.
IMPACT ON GEOLOGY

16.  Morphology of the delta have shifted 12 km eastward
from the original lower Volta entre point to the sea
leading to coastal erosion at Ada.
 In accordance with the behaviour of tropical dam
microclimate the temperature and rainfall in the south
eastern part of Ghana is higher than the average in other
parts of the basin.
IMPACT ON GEOLOGY (contd.)

17. POLITICAL MOTIVES
 Initially 20% of Akosombo Dam's electric output (serving 70% of
national demand) was provided to Ghanaians in the form of
electricity, the remaining 80% was generated for the American-
owned Volta Aluminum Company (VALCO).
 The Ghana Government was compelled, by contract, to pay for
over 50% of the cost of Akosombo's construction, but the country
was allowed only 20% of the power generated.
 Neocolonialism - Power to make decisions about development
(sustainable or otherwise) provided to powerful actors (the Prime
Minister of Ghana, the Ghanaian Government, the World Bank, the
USA, the UK, the Export-Import Bank of America, and several
companies) Ideally, those people would have been enabled made
decisions that affected the lives of rural fishers and farmers who
had scarce power, representation or resources. to participate in a
decision-making process that was to have such profound
implications for their lives.

18. CONTROVERSIES
STRENGTH WEAKNESS
The Akosombo HEP provides over 85%
of all electricity generated in Ghana which
encouraged economic and industrial
development in Ghana
Today an estimated 60% of the population has
access to electricity including 20% of the rural
communities. Urban dwellers are being more
beneficial than the people affected by the
dam.
Over two-thirds of all the electricity
generated goes to industries and
commercial entities leading to rapid
expansion and immigration of industries
into Ghana and resulting Ghana’s
economy is twice the average of the West
African sub region.
Ghana’s overreliance on HEP have hamper the
development of alternative renewable energy
sources which have affected the country in
times of drought. In years of drought where
HEP energy generation has been poor,
unemployment rate rises exponential attesting
to a positive externality of the Akosombo dam
Sustainable Development Akosombo Dam involved a trade-off between
environment and development.
It created, rather than reduced, poverty for
many people (those who were displaced by the
creation of Lake Volta).

19. OPPORTUNITIES THREATS
VRA undertook some activities towards the
fulfillment of non-generation goals like the
creation of the Akosombo Textiles Company,
Kpong Farms Limited, the Akosombo Hotel
Limited and Volta Lake Transport Company
Limited (VLTC) to boast jobs and economic
activity within the region.
Inhabitants did not have the specialized
skills and education levels required to take
advantage of working in textiles industries
or operating advanced machinery in the
1960’s.
The generation of electricity as stated earlier
lead to the positive economic and industrial
development along the eastern coast of Ghana.
Even after 50 years of operation, that the
majority of the affected people by the
project were not connected to the national
grid until recently .
Large-scale irrigation, modernization of
agriculture, promotion of factories and
industries, and the establishment of tourist
facilities
The resettlement of the communities and
the compensation promised to the
inhabitants were not fully paid, farming
lands were insufficient for the villages.
VRA irrigation and modernization of
agriculture programs collapsed.
CONTROVERSIES (contd.)

20.  https://en.wikipedia.org/wiki/Akosombo_Dam
 https://www.ukessays.com/essays/environmental-
sciences/case-study-of-the-akosombo-hydroelectric-
dam-environmental-sciences-essay.php
 https://www.soas.ac.uk/cedep-demos /000
_P501_USD_K3736-Demo/unit1/page_19.htm
 https://www.vra.com/resources/annual_reports/2010.pdf
 https://www.britannica.com/topic/Akosombo-Dam
REFERENCES