|Construction cost||£130 million|
|Owner(s)||Volta River Authority|
|Dam and spillways|
|Type of dam||Embankment, rock-fill|
|Height (foundation)||114 m (374 ft)|
|Length||660 m (2,170 ft)|
|Width (base)||366 m (1,201 ft)|
|Dam volume||7,900,000 m3 (280,000,000 cu ft)|
|Spillway capacity||34,000 m3/s (1,200,000 cu ft/s)|
|Total capacity||148 km3 (120,000,000 acre⋅ft)|
|Surface area||8,502 km2 (3,283 sq mi)|
|Maximum length||400 km (250 mi)|
|Hydraulic head||68.8 m (226 ft) (max)|
|Turbines||6 x 170 MW (230,000 hp) Francis-type|
|Installed capacity||1,038 MW (1,392,000 hp)|
The Akosombo Dam, also known as the Volta Dam, is a hydroelectric dam on the Volta River in southeastern Ghana in the Akosombo gorge and part of the Volta River Authority. 8,502 square kilometres (3,283 sq mi), which is 3.6% of Ghana's land area. With a volume of 148 cubic kilometers, Lake Volta is the world's third largest man-made lake by volume, the largest being Lake Kariba which is located between Zimbabwe and Zambia in Southern Africa and contains 185 cubic kilometers of water.The construction of the dam flooded part of the Volta River Basin, and led to the subsequent creation of Lake Volta. Lake Volta is the largest man-made lake in the world by surface area. It covers
The primary purpose of the Akosombo Dam was to provide electricity for the aluminium industry. 912 megawatts (1,223,000 hp), which was upgraded to 1,020 megawatts (1,370,000 hp) in a retrofit project that was completed in 2006.The Akosombo Dam was called "the largest single investment in the economic development plans of Ghana." The dam is also significant for providing the majority of both Togo and Benin's electricity, although the construction of the Adjarala Dam hopes to reduce these countries' reliance on imported electricity. The dam's original electrical output was
The flooding that created the Lake Volta reservoir displaced many people and had a significant impact on the local environment,including seismic activity that led to coastal erosion; a changed hydrology caused microclimatic changes with less rain and higher temperatures. The soil surrounding the lake is less fertile than the soil under it, and heavy agricultural use has required the use of fertilizers, which in turn has led to eutrophication, which caused, among others, the explosive growth of an invasive weed that renders water navigation and transportation difficult, and form a habitat for the vectors of water-borne illnesses such as bilharzia, river blindness and malaria. Resettlement of the displaced inhabitants proved complex and in some cases unsuccessful; traditional farming practices disappeared and poverty increased.
The dam was conceived in 1915 by geologist Albert Ernest Kitson, but no plans were drawn until the 1940s.The development of the Volta River Basin was proposed in 1949, but because funds were insufficient, the American company Volta Aluminum Company (Valco) lent money to Ghana so that the dam could be constructed. Kwame Nkrumah adopted the Volta River hydropower project.
The final proposal outlined the building of an aluminum smelter at Tema, a dam constructed at Akosombo to power the smelter, and a network of power lines installed through southern Ghana. The aluminum smelter was expected to eventually provide the revenue necessary for establishing local bauxite mining and refining, which would allow aluminum production without importing foreign alumina. Development of the aluminum industry within Ghana was dependent upon the proposed hydroelectric power. million.The proposed project's aluminum smelter was overseen by the American company, Kaiser Aluminum, and is operated by Valco. The smelter received its financial investment from Valco shareholders, with the support of the Export-Import Bank of Washington, DC. However, Valco did not invest without first requiring insurances from Ghana's government, such as company exemptions from taxes on trade and discounted purchases of electricity. The estimated total cost of the project, in its entirety, was estimated at $258
In May 1960, the Ghana government called for tenders for construction of the hydroelectric dam. In 1961, an Italian consortium, Impregilo which had just completed the Kariba Dam, won the contract. They carried out the dredging of the river bed and dewatering of the channel, and completed the dam a month earlier than scheduled despite flooding of the Volta River in 1963 which delayed work over three months. Between 1961 and 1966, 28 workers of Impregilo died during the construction of the dam. Memorials in Akosombo township and St. Barbara Catholic Church have been put up in their honor.[ citation needed ]
In 1961, the Volta River Authority (VRA) was established by Ghana's Parliament through the passage of the Volta River Development Act. The VRA's fundamental operations were structured by six Board members and Kwame Nkrumah as chairman. The VRA's primary task is to manage the development of the Volta River Basin, which included the construction and supervision of the dam, the power station and the power transmission network. The VRA is responsible for the reservoir impounded by the dam, the fishing within the lake, lake transportation and communication, and the welfare of those surrounding the lake.
The dam was built between 1961 and 1965.Its development was undertaken by the Ghanaian government and funded 25% by the International Bank for Reconstruction and Development of the World Bank, the United States, and the United Kingdom.
The construction of the Akosombo dam resulted in the flooding of part of the Volta River Basin and its upstream fields, and in the creation of Lake Volta which covers 3.6% of Ghana's total land area. people, who represented 1% of the population. People of 700 villages were relocated into 52 resettlement villages two years prior to the lake's completion; the resettlement program was under the direction of the VRA. Two percent of the resettlement population were riparian fishers and most were subsistence farmers. The Eastern Region of Ghana and the populations incorporated within its districts, were most subject to the project's effects.Lake Volta was formed between 1962 and 1966, and necessitated the relocation of about 80,000
In the beginning of 2007, concerns were expressed over the electricity supply from the dam due to low water levels in the Lake Volta reservoir. 84.45 m (277 ft), and for several weeks, water was spilled from the lake, causing some flooding downstream.Some sources said this was due to problems with drought that are a consequence of global warming. During the latter half of 2007, much of this concern was abated when heavy rain fell in the catchment area of Volta River. In 2010, the highest-ever water level was recorded at the dam. This necessitated the opening of the flood gates at a reservoir elevation of
The dam is 660 m (2,170 ft) long and 114 m (374 ft) high, comprising a high rock-fill embankment dam. It has a base width of 366 m (1,201 ft) and a structural volume of 7,900,000 m3 (10,300,000 cu yd). The reservoir created by the dam, Lake Volta, has a capacity of 148 km3 (120,000,000 acre⋅ft) and a surface area of 8,502 km2 (3,283 sq mi). The lake is 400 km (250 mi) long. Maximum lake level is 84.73 m (278.0 ft) and minimum is 73.15 m (240.0 ft). On the east side of the dam are two adjacent spillways that can discharge about 34,000 m3/s (1,200,000 cu ft/s) of water. Each spillway contains six 11.5-metre (38 ft)-wide and 13.7-metre (45 ft)-tall steel floodgates.
The dam's power plant contains six 170-megawatt (230,000 hp) Francis turbines. Each turbine is supplied with water via a 112–116-metre (367–381 ft) long and 7.2-metre (24 ft) diameter penstock with a maximum of 68.8 m (226 ft) of hydraulic head afforded.
The dam provides electricity to Ghana and its neighboring West African countries, including Togo and Benin. 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. Some commentators are concerned that this is an example of neocolonialism. In recent years the production from the VALCO plant has declined with the vast majority of additional capacity in Akosombo used to service growing domestic demand.
The Akosombo Dam benefited some industrial and economic activities from the addition of lake transportation, increased fishing, new farming activities along the shoreline, and tourism.The power generated has provided for primary interests within Ghana, while also supplying power to the neighboring countries of Togo and Benin. Ghana's industrial and economic expansion triggered a higher demand for power, beyond the Akosombo's power plant capabilities. By 1981, a smaller dam was built at the town of Kpong, downstream from Akosombo and further upgrades to Akosombo have become necessary for maintaining hydropower output. Initially, the dam's power production capabilities greatly overreached the actual demand; while, the demand since the dam's inception has resulted in the doubling of hydropower production. Increasing demands for power exceed what can be provided by the current infrastructure. Power demands, along with unforeseen environmental trends, have resulted in rolling blackouts and major power outages. An overall trend of lower lake levels has been observed, sometimes below the requirement for operation of the Akosombo Dam.
In the time following the construction of the dam at Akosombo, there has been a steady decline in agricultural productivity along the lake and the associated tributaries.The land surrounding Lake Volta is not nearly as fertile as the formerly cultivated land residing underneath the lake, and heavy agricultural activity has since exhausted the already inadequate soils. Downstream agricultural systems are losing soil fertility without the periodic floodings that brought nutrients to the soil before the natural river flow was halted by the dam. The growth of commercially intensive agriculture has produced a rise in fertilizer run-off into the river. This, along with run-off from nearby cattle stocks and sewage pollution, has caused eutrophication of the river waters. The nutrient enrichment, in combination with the low water movement, has allowed for the invasion of aquatic weeds ( Ceratophyllum ). These weeds have become a formidable challenge to water navigation and transportation.
The presence of aquatic weed along the lake and within the tributaries has resulted in even greater detriment to local human health. The weeds provide the necessary habitat for black-fly, mosquitoes and snails, which are the vectors of water-borne illnesses such as bilharzia, river blindness and malaria.Since the installment of the dam, these diseases have increased remarkably. In particular, resettlement villages have shown an increase in disease prevalence since the establishment of Lake Volta, and a village's likelihood of infection corresponds to its proximity to the lake. Children and fishermen have been especially hard hit by this rise of disease prevalence. Additionally, the degradation of aquatic habitat has resulted in the decline of shrimp and clam populations. The physical health of local communities has been diminished from this loss of shellfish populations, as they provided an essential source of dietary protein. Likewise, the rural and industrial economies have experienced the financial losses associated with the decimation of river aquaculture.
The loss of land experienced by the 80,000 people forcibly relocated meant the loss of their primary economic activities from fishing and agriculture, loss of their homes, loss of their family grave sites, loss of community stability, and the eventual loss of important social values. The resettlement program demonstrated the social complexities involved in establishing "socially cohesive and integrated" communities. Insufficient planning resulted in the relocation of communities into areas that were not capable of providing for their former livelihoods and traditions. The loss of the naturally fertile soils beneath Lake Volta essentially led to the loss of traditional farming practices. The poor living conditions provided within the resettlement villages has been demonstrated by population reductions since resettlement. One resettlement village in particular experienced a greater than 50% population reduction in the 23 years following relocation. Increased economic risks and experiences of poverty are associated with those communities most impacted by the Volta River's development. The extensive human migration and degradation of natural resources within the Volta-basin area, are the products of poverty in conjunction with population pressure.
Increased human migration within the area has been driven by poverty and unfavorable resettlement conditions.This migration enabled the contraction of HIV and has since led to its heightened prevalence within Volta Basin communities. The districts of Manya Krobo and Yilo Krobo, which lie within the southwest portion of the Volta Basin, are predominantly indigenous communities that have attained a disproportionate prevalence of HIV. The situation underlines the strength of the local factors upon these districts. Commercial sex work was established in response to the thousands of male workers that were in the area for building the dam. Ten percent of the child-bearing females from these two districts migrated out of their districts during this time. In 1986, "90% of AIDS victims in Ghana were women, and 96% of them had recently lived outside the country".
The Akosombo Dam and other dams of the Volta River Hydro Development Project increased substantially the conditions for the spread of schistosomiasis.
Reservoir-induced seismicity has been recorded due to the crustal re-adjustments from the added weight of the water within Lake Volta.There is an eastward shift of the river's mouth from the changes to the river's delta zone and this has led to continuing coastal erosion. The changes in the river hydrology have altered the local heat budget which has caused microclimatic changes such as decreasing rain and higher mean monthly temperatures. All of these larger scale environmental impacts will all further compound the problems surrounding disruptions to local economic activities and associated, difficult human welfare conditions. A case study by the International Federation of Surveyors has indicated that the dam has had a significant impact on the shoreline erosion of the barrier separating the Keta Lagoon from the sea. Dr. Isaac Boateng has calculated the reduction of fluvial sediment as being from 71 million cubic metres per year to as little as 7 million cubic metres per year.
Ghana is a West African country in Africa, along the Gulf of Guinea, just a few degrees north of the equator.
The Volta River is the main river system in the West African country of Ghana. It flows south into Ghana from Bobo-Dioulasso highlands of Burkina Faso. The main parts of the river are the Black Volta, the White Volta, and the Red Volta. In the northwest, the Black Volta forms the international borders between the Ivory Coast, Ghana, and Burkina Faso. The Volta flows southward along Akwapim-Togoland highlands, and it empties into the Atlantic Ocean at the Gulf of Guinea at Ada Foah. It has a smaller tributary river, the Oti, which enters Ghana from Togo in the east. The Volta River has been dammed at Akosombo for the purpose of generating hydroelectricity. The reservoir named Lake Volta stretches from Akosombo Dam in the south to the northern part of the country, and is the largest man-made reservoir by area in the world.
Lake Nasser is a vast reservoir in southern Egypt and northern Sudan. It is one of the largest man-made lakes in the world. Before construction, Sudan was against the building of Lake Nasser because it would encroach on land in the North, where the Nubian people lived. They would have to be resettled. In the end Sudan's land near the area of Lake Nasser was mostly flooded by the lake.
Lake Volta, the largest artificial reservoir in the world based on surface area, is contained behind the Akosombo Dam which generates a substantial amount of Ghana's electricity. It is completely within the country of Ghana and has a surface area of 8,502 square kilometres. It extends from Akosombo in the south to the northern part of the country.
The Atatürk Dam, originally the Karababa Dam, is a zoned rock-fill dam with a central core on the Euphrates River on the border of Adıyaman Province and Şanlıurfa Province in the Southeastern Anatolia Region of Turkey. Built both to generate electricity and to irrigate the plains in the region, it was renamed in honour of Mustafa Kemal Atatürk (1881–1938), the founder of the Turkish Republic. The construction began in 1983 and was completed in 1990. The dam and the hydroelectric power plant, which went into service after the upfilling of the reservoir was completed in 1992, are operated by the State Hydraulic Works (DSİ). The reservoir created behind the dam, called Atatürk Reservoir, is the third largest in Turkey.
The Keban Dam is a hydroelectric dam on the Euphrates, located in the Elazığ Province of Turkey. The dam was the first and uppermost of several large-scale dams to be built on the Euphrates by Turkey. Although the Keban Dam was not originally constructed as a part of the Southeastern Anatolia Project (GAP), it is now a fully integrated component of the project, which aims to stimulate economic development in Southeastern Turkey. Construction of the dam commenced in 1966 and was completed in 1974. Keban Dam Lake, the reservoir created by Keban Dam, has a surface area of 675 square kilometres (261 sq mi) and is reputedly the fourth-largest lake in Turkey after Lake Van, Lake Tuz, and the reservoir created by the Atatürk Dam.
The Nechako River arises on the Nechako Plateau east of the Kitimat Ranges of the Coast Mountains of British Columbia, Canada, and flows north toward Fort Fraser, then east to Prince George where it enters the Fraser River. "Nechako" is an anglicization of netʃa koh, its name in the indigenous Carrier language which means "big river".
A reservoir is most commonly an enlarged natural or artificial lake created using a dam to store fresh water.
Volta Aluminum Company, known as VALCO, is an aluminium company based in Tema, Greater Accra Region founded by Kaiser Aluminum and now wholly owned by the government of Ghana.
The Volta River Authority (VRA) is the main generator and supplier of electricity in Ghana. They are also the responsible for the maintenance of the hydro power supply plant.
The Bui Dam is a 400-megawatt (540,000 hp) hydroelectric project in Ghana. It is built on the Black Volta river at the Bui Gorge, at the southern end of Bui National Park. The project is a collaboration between the government of Ghana and Sino Hydro, a Chinese construction company. Construction on the main dam began in December 2009. Its first generator was commissioned on 3 May 2013, and the dam was inaugurated in December of the same year.
The Kenney Dam is a rock-fill embankment dam on the Nechako River in northwestern British Columbia, built in the early 1950s. The impoundment of water behind the dam forms the Nechako Reservoir, which is also commonly known as the Ootsa Lake Reservoir. The dam was constructed to power an aluminum smelter in Kitimat, British Columbia by Alcan, although in the late 1980s the company increased their economic activity by selling excess electricity across North America. The development of the dam caused various environmental problems along with the displacement of the Cheslatta T'En First Nation, whose traditional land was flooded.
Industry in Ghana accounts for about 25.3% of total GDP. However, Ghana's industrial production is rising at a 7.8% rate, giving it the 38th fastest growing industrial production in the world due to government industrialization policies.
Ghana generates electric power from hydropower, fossil-fuel, and renewable energy sources. Electricity generation is one of the key factors in order to achieve the development of the Ghanaian national economy, with aggressive and rapid industrialisation; Ghana's national electric energy consumption was 265 kilowatt hours per capita in 2009.
The Nechako Reservoir, sometimes called the Ootsa Lake Reservoir, is a hydroelectric reservoir in British Columbia, Canada that was formed by the Kenney Dam making a diversion of the Nechako River through a 16-km intake tunnel in the Kitimat Ranges of the Coast Mountains to the 890 MW Kemano Generating Station at sea level at Kemano to service the then-new Alcan aluminum smelter at Kitimat. When it was constructed on the Nechako River in 1952, it resulted in the relocation of over 75 families. It was one of the biggest reservoirs built in Canada until the completion of the Columbia Treaty Dams and the W.A.C. Bennett Dam that created Lake Williston. The water level may swing 10 feet between 2790 and 2800 feet.
Corra Linn Dam is a concrete hydroelectric dam on the Kootenay River between the cities of Castlegar and Nelson, in the West Kootenay region of southern British Columbia.
The Kpong Dam, also known as the Akuse Dam, is a hydroelectric power generating dam on the lower Volta River near Akuse in Ghana. It is owned and operated by Volta River Authority. It was constructed between 1977 and 1982. Its power station has a capacity of 148 megawatts (198,000 hp) with all four units running, though the total nameplate capacity is 160 megawatts (210,000 hp).
Dodi Princess was a cruise boat on Lake Volta in South Ghana. It was owned by the Volta River Authority and under the management of Volta Hotels. It was the only cruise ship in Ghana. It was built as a cargo ship and later converted into a passenger ship in 1991.
Volta Hotels Limited is Strategic Business Unit instituted by the Volta River Authority (VRA), in Ghana.
Louis Casely-Hayford was a Ghanaian chartered engineer who served as the third CEO of the Volta River Authority (VRA) from 1980 to 1991. He was CEO of the VRA when the master-plan for extension of electricity to the northern parts of Ghana was conceived. He led the creation of the VRA Training School, which trained engineers, technicians and other disciplines needed to support the power sector of Ghana. Casely-Hayford also played monumental roles as CEO in the development of Kpong Power Project.
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