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Wikipedia Article First Draft

Cahora Bassa Dam (exists)
The Cahora Bassa dam is located in Mozambique, a country that boarders South Africa. And was finished in December 1974 after much political debate. This dam is used to convert the Zambezi River power into electricity by turning turbines. That energy is then sent to South African cities, farms, and mines. The Cahora Bassa dam is on the Cahora Bassa Lake which is shared between Mozambique and Portugal. Eighteen percent of the dam and lake is owned by Mozambique and eighty-two percent is owned by Portugal. The Cahora Bassa dam is the largest hydroelectric power plant in southern Africa and the most efficient power generating station in Mozambique.

History (exists)
Before the Cahora Bassa dam underwent construction, the native people protested the dam in order to keep their land. The Portuguese colonial government gave order to construct this dam. Today, the Portuguese government owns eighty-two percent of the Cahora Bassa Lake and the Cahora Bassa dam while the country the lake and dam lie in only owns eighteen percent. When given the order to begin construction in 1969, the colonial government of Portugal forced the native people out of their homes and villages in order for the Portuguese and European workers to have a place to live during construction. The Cahora Bassa dam was built in order for more power to go to South Africa. The Portuguese government built a small town for all the contractors, electricians, and engineers on top of the native Mozambique homes. The evicted native people were not given compensation for their loss of property. The dam was built to produce electricity for South African farms, mines, and cities. Since the dam transfers the electricity that it creates to South Africa, it is taking electricity away from the natives that were able to keep some of their land. The natives now struggle for electricity and a regular supply of clean drinking water. In recent years, the annual rainfall has been decreasing. Before 2010, the average annual rainfall was thirty-seven inches. This average has been decreasing ever since and last year, the average annual rainfall was twenty-five inches. If this average continues to fall, the dam operators may have to shut off the flow to some or even all the turbines. Doing so will conserve the water and energy until the reservoir is full enough to allow water to spin the turbines and create more electricity.

Power Stations (exists)
The Cahora Bassa dam contains five 415 megawatt turbines. The amount of water that flows through these turbines makes this dam the largest hydroelectric plant in southern Africa. 1,450 megawatts get generated from the water passing through the five turbines. This power is transferred over 1,800-kilometers (1100 miles) of high voltage direct current lines that run from Songo to the power grids of South Africa to power South African cities, farms, and mines. These Lines must be high above ground, so they run through tall towers called pylons. The pylons take the high voltage direct current lines from the generators and bring them away from the ground for safety. The pylons are evenly separated and support the high voltage lines from the dam to the South African power grids.

How It Works
The Movement of water creates hydroelectric energy. In order to contain that energy and control it, a dam or reservoir is used. As the reservoir is filled by a movement or flow of water, such as a river, the water is concentrated through tunnels in the dam. As the water flows through those tunnels, it spins turbines which turn generators. These generators create electricity by turning. That electricity can either be used directly, such as an electric motor, or it can be stored for later use, similar to batteries. Hydroelectricity in the Cahora Bassa dam works by the Zambezi river running into the reservoir created by the dam. That water then flows through tunnels where the five turbines are located. The concentrated flow of water spins the turbines which turn the generators that send electricity through the 1,800-kilometers (1100 miles) of high voltage direct current lines. These lines are held up by tall metal towers that run from the dam in Mozambique to a South African converter station that converts the direct current into usable electricity for cities, farms, and mines.

References

Cahora Bassa Dam (exists)

International Lake Environment Committee. (2018). World Lake Database. Retrieved from	http://wldb.ilec.or.jp/Details/lake/AFR-14 The dam was finished December 1974.

Mozambique History Net. (2010). Cahora Bassa, 1969-1995. Retrieved from	http://www.mozambiquehistory.net/cahora_bassa_2.php Portugal owns 82% of the dam and Mozambique owns 18%.

Power Stations (exists)

Isaacman, A. F., & Isaacman, B. S. (2013). Dams, displacement, and the delusion of	development: Cahora Bassa and its legacies in Mozambique: 1965-2007. Athens, OH:	Ohio University Press. Retrieved from	https://ebookcentral.proquest.com/lib/csum/reader.action?docID=1743645&query Displaces the energy from Mozambique by converting the Zambezi Rivers power into electricity for South Africa.

Sommer, U., & Gliwicz, Z. (1986). Long Range Vertical Migration of Volvox in Tropical Lake Cahora Bassa (Mozambique). Limnology and Oceanography, 31(3), 650-653. Retrieved from http://www.jstor.org/stable/2836880 The dam transports 530-megawatts to South Africa by using an 870-mile long transmission line.

History (exists)

Earth Observatory. (2016). The Ring Around Lago de Cahora Bassa. Retrieved From	https://earthobservatory.nasa.gov/IOTD/view.php?id=88558 Now the lake is only 31% full and may have to shut down the turbines in the dam.

Mozambique History Net. (2010). Cahora Bassa, 1969-1995. Retrieved from	http://www.mozambiquehistory.net/cahora_bassa_2.php History of how portugual owns 82%.

Isaacman, A. (2005). Displaced People, Displaced Energy, and Displaced Memories: The Case of	Cahora Bassa, 1970-2004. The International Journal of African Historical Studies, 38(2),	201-238. Retrieved from http://www.jstor.org/stable/40034919 Natives were forced to leave their homes without compensation.

Sebitosi, A. & Graça, A. (2009). Cahora Bassa and Tete Province (Mozambique): A great potential for an industrial hub in Southern Africa. Science Direct, 37 (5), 3-8. Retrieved from https://www.sciencedirect.com/science/article/pii/S0301421509000081 Today, the natives fight for water and electricity.

Bohensky, E., & Lynam, T. (2005). Evaluating Responses in Complex Adaptive Systems: Insights on Water Management from the Southern African Millennium Ecosystem Assessment (SAfMA). Ecology and Society, 10(1). Retrieved from http://www.jstor.org/stable/26267744 Tie in the annual rainfall to how low the lake is.

How It Works

National Geographic Society. (2012, October 09). Hydroelectric energy. Retrieved March 22, 2018, from https://www.nationalgeographic.org/encyclopedia/hydroelectric-energy/

Picture citation

Beilfuss, R. (Political Activist Against the Dam). (2012). Cahora Bassa Dam, Retrieved from: https://www.flickr.com/photos/internationalrivers/7997875257/in/photolist Peer Review comments: Right after source "4", there is a sentence that seems repetitive about the dam making power, maybe add the importance or the impact of the dams additional power as well. Under the history subheading there are a few places that the tense are switched, maybe stick to past tense for flow. Maybe a little more detail of how turbines convert the water's mechanical energy to electrical I feel that would help a reader who has no clue of how energy or dams work a better insight. Good information that is easy to follow on the science behind the dam. Great sources. Very relevant information that stay consistent to the topic.