Kariba dam was built between 1956 and 1963 and by that time was the largest manmade lake in the world-lake kariba. It was officially opened by the queen of England, Queen Elizabeth the second on May 16th 1960. At that time it was Africa’s most ambitious project switching the first electric generators of the time. A double concrete curvature arched dam wall was standing at above 128metres above the river bed. It was also a stretch of 617metres across the gorge of kariba on Africa’s second largest river-river Zambezi (Jansen,8).
The dam created a stretching inland sea 280km in length and covering a 5500 square kilometer and holding over 180 billion tonnes of water. It holds two important power generating stations on the south. The kariba north bank power station which is strategically located on the Zambian side. Kariba south bank power station, and on their neighbor country Zimbabwe. The power stations generates a totally of 1320 megawatts of electricity. Costing around $1.2 billion in 1998, the construction had a major impact on Zambian development economy transforming the southern part infrastructure and creating multiple job opportunities (Tumbare, 9).
The Batonga people however were displaced from the Zambezi valley which was their ancestral home for many years to make way for the rising waters. The creation of Kariba Lake not only gave birth to a vibrant fishing industry in commercial aspects but also continuously developed the tourism sector offering the most spectacular scenic adventure with a diversity of both flora and fauna. It also provides room for hotel accommodation, water sports, sports fishing and house boating among a variety of other great tourism adventures.
Although the building of the dam was supposed to usher in a good future for the communities it remains to be seen. A total of 57000 people were displaced from both Zimbabwe and Zambia for the Gwembe Tonga and kore kore people the Kariba dam was a grave dug for their communities and culture. They had lived for many years along the banks of river Zambezi though compensated with land at a place called Sitikwi was marginal and not arable for subsistence farming. The 57000 indigenous people were given no choice about the construction of the dam. Some resisted but were forcefully displaced by the long hand of the lawful colonial masters that culminated into the “Chisamu” . Their homes were burnt; the communities struggled to make end meets in their daily lives. They were promised electricity services and irrigation projects in their new areas (Tumbare, 34).
However in sharp contrast of events most live without this basic service. Hospital schools and other social amenities are scarce, ill equipped and not adequate. The Kore kore and Gwembe tonga people have been for long searching for solutions and redress to their problems. This is led by powerful traditional leader and other local non-governmental organizations. Both government, the Zambian and Zimbabwean have failed to deliver on their promises throughout this years and thus making the indigenous people live in deplorable conditions.
Much of what happens as consequence appears to be a common phenomenon in all aspects. The result of forceful displacement is a period of upheaval in both social and economic demographic expected to last between three to six years before indigenous establishes them as a settled lot. It’s a period where much hostility is aimed at government and its officials who are seen to disregard in totality the interest of the people at the expenses of such a massive construction project into advanced other section. This officials rule more by force and less by consent. In this case religious practices of such people come into question when people are more vulnerable to insecurity and fear. The desire of kinsmen to be together in close proximity diffuses tension internally and within.
In the period between 1890s a feasibility study was done by the colonial government but the Zambezi in both north and south Rhodesia. It was cited as a potential crossing point for a railway bridge across the Zambezi connecting north Rhodesia to south Rhodesia. With difficulty in railway construction the objective changed to construction of a large dam for provision of hydroelectric power to mining and manufacturing industry to burgeoning. A discovery of copper in Zambia between 1920 to 1945 and with increasing demand for copper during the world war two, both mining and manufacturing industries in north and south Rhodesia currently Zambia and Zimbabwe grew rapidly. At the time mines were supplied with electricity from small coal power stations located on the copper belt.
Coal was being supplied from coal fields in Zimbabwe in South Africa. Large distances exceeding 750 kilometers provided large challenges during transportation of coal to the industry. The single track railway line connecting the copper belt with the colliery proved largely incapable of withstanding increasing tonnages of coal. This led to need for creation of alternative source of power for industry to run. The new source of power had to be found with speed which led to the construction of the kariba dam.
In 1946, a committee known as the Inter-Territorial Hydro Electric power committee. It was closely followed in 1948 by the appointment of an advisory committee to decide on relative merits and demerits of construction of the two electric power station on river Kafue and river Zambezi. The committee initially recommended for the construction of kariba dam due lacking of information on Kafue river. Though costly Kariba dam proved much easier to construct due to many pros. Northern and southern Rhodesia were British colonies, they were however autonomous and independent with different ideologies on governance. One was a settlement colony while the other was a protectorate “indirect rule colony”.
There was a great degree of mistrust followed by political differences which were evident in deciding which of the two dams would be constructed first. The need for electricity on the copper belt in the northern Rhodesia was keen to see Kafue dam constructed first. On the other hand Kariba dam was to produce more megawatts and could supply both the south and the north where shortages were seen thus Kariba dam though costly than Kafue dam was recommended to be constructed first. The dam would as see thrive in commercial fishing industry and both domestic and international tourism boost the economies of both countries.
The electricity demand of northern Rhodesia necessitated the construction of Kafue stream ahead of Kariba dam. Things were to get complicated with the formation of federation of Rhodesia and Malawi in 1950s. Further still the political infighting over which site to develop first became intense
The debate continued for almost two years with aspects of estimation (under and over) for both Kafue and kariba projects. It was the desire of the federal government to bring together both project and the political position of the two governments concerning the projects. Finally, external experts were sought by the government through the hydroelectric board in 1954. The experts view was that Kariba was more viable than Kafue as the best and most acceptable politically. In 1955, the federal government concurred with the experts’ opinion and construction began officially.
Although both projects were considered the merits were in favor of Kariba but they both needed to supply hydroelectric power to the ever increasing demand for power. Kariba was planned in two phases for a period of fifteen years. Phase one included the construction of the dam wall and construction of south bank power station while the second phase was construction of north bank power station which was due to start in 1965.
Phase one was financed by various subsectors both locally and internationally. World Bank was the main financier internationally with copper mining companies, government institutions, parastatals, and commercial companies including bank producing the bulk of domestic financing. In 1956 preparation of earth and area clearing began in earnest; it was completed in 1960 ahead of planned time and overall budget estimates. There were various challenges that affected construction of Kariba dam and the main one was increase in level of water due to flooding in the year 1957 and 1958 respectively.
The dam was flooded as the water rose above the three meters above the norm. Construction was stopped for three months as the situation proved un workable due to the raging waters. Work resumed when the flood waters subsidized. A redesign of the dam wall was put in place after floods that happened in 1958 and 1957.the wall was raised by additional six meters and two additional flood gates. By the end of the same year contractors were able contain the perennial floods of river Zambezi with progressive the construction of wall.
Encroaching kariba dam, are the Batonga tribe, who believed that perennial floods that wreaked havoc to their people was “River God” known as Nyami Nyami.A Popular myth among the Batonga people was that wife to Nyami Nyami descended down to the stream kariva,presently known as kariba Gorge, to carry out her religious duty. Then when time came for her to return back home, she couldn’t because of the dam wall. According to the myth, this incensed Nyami Nyami so much that that he ordered the water levels to rise and destroy the wall.
The social implication of the construction of the dam was never considered in the first case.it was during the colonial days and as such little attention was paid to over 50,000 inhabitants of Zambezi valley that would be affected by the floods from the rising water levels. The Batonga people so steeped in their culture and tradition did not to see themselves having to contend with floods from the river Zambezi. They put up a spirited opposition to vacate from their lands in the belief that government had conspired to take their fertile lands. They did however concede to the order to leave their land after incurring losses.
People had to be resettled to higher lands at the cost borne by the federal hydroelectric board. The resettlement was the issue of respective governments of northern and southern Rhodesia. The resettlement was different as both regions were semi-autonomous. Those from northern Rhodesia were lucky to receive compensations. They were to include compensations for the loss of earning time while clearing new lands, customary rights and land rights. Things were not that good for the Southern Rhodesia who was only provided with food during the resettlement and annual tax exemptions for males.
The resettlement had its demerits to the people. People who were relocated to Zambia had proximity to the lake though they had been moved to higher lands. They were allocated lands that were poor and that could not produce crops throughout the year owing to the distance to the river. Resettling many people in some piece of land had its own challenges, food security was hard to guarantee with diminished food production. Communal ties were broken as people who were related or shared a identity could not see each other as they used to. In 1963 with the breakdown of federation between the Rhodesia and Nyasa land and birth of republic of Zambia in 1964 people were disintegrated more. Free movement was not possible with borders being put in place, relatives and friends couldn’t see each other like they used to, with the developments, the culture, traditions and values were slowly eroded.
The people of Batonga lost so much. Before the construction of the dam they had access to hospital, schools and accessibility to the area. They had lost their treasured traditions and beliefs and importantly the fertile lands. Tonga people may have adjusted to changes in their lives by seeking better lives away but historical injustices will be stark reminder of what they lost. In Zambia, there has been a response by the initiative of the World Bank fund to mitigate the socio-economic challenges of resettlement known as Gwembe-Tonga Rehabilitation and Development Program.
The actual building of the dam took off in 1959. The vegetation had to be cleared to pave way for the sites. That provided the lake with chemical deposit of burnt. The remnant trees provide habitant to the animals that came to reside in the lake.it involved pouring of many millions of concrete slab to attain a height of 30 meters and width of over 20 meters, enough to withstand the pressure of millions of cubic waters passing it in a second. The mighty Zambezi River flows through 8 different countries that include Angola, Tanzania, Mozambique, Malawi, Zimbabwe, Namibia, Zambia and Botswana.it covers approximately 2650 kilometers from its source to the Indian ocean.kariba dam was located halfway river Zambezi.
Kariba was designed by a French engineer and arch dam design specialist. He had helped to come up with various dams design. This in 1955 when then the federation of northern Rhodesia and southern Rhodesia invited tenders for the construction of dam wall after mulling over which project to get ahead with between kariba and Kafue scheme. The award of tender was given to an Italian firm. Hailed as one of the engineering marvel and piece of art to have graced the planet, it had its own fair share of challenges. The floods defied the probability of designers to wreak havoc to the construction work that was going on. The water levels soured high with immense power that some equipment was destroyed and roads rendered impassable in 1957(Jansen, 45). It is said the water levels soured three meters more than the previous level at that time.
The dam has special relationship with Batonga people. They had their own explanations to devastating floods.
Construction of kariba dam included the following in its project appraisal. Engineering works at a cost of £33.9million. The contingencies of engineering works were £6.75million. It also required installation of electrical and mechanical plants and it’s contingencies at a combined total £7.84million. There were also transmission line system valued at £12.6million, substations and contingency engineering works £6.86million. The federal hydroelectric board had the following cost; £4million for resettlement of the indigenous Gwambatonga people, preliminary expenses of £0.8million. The interest accrued during construction of both phases of kariba was £7.15million, this brought to a total for the whole construction of £79.38million. there were however certain challenges that faced this project and this were, price escalation especially in civil construction brought about by changes in oil prices due to reorganization of Organization of Petroleum Exporting Countries (OPEC), changes in currency exchange rate and changes in interest rate during construction.
In my analysis a dam would be the most important feature to construct at present time. Construction of a dam would be most important for protection of people living near river banks against flooding in case the levels of water of the river rises and causing its banks to burst. The construction of these dams has been using established methods in the United States, Asia and Europe. This methods use asphalts which improve protection methods and low construction methods and also there’s low maintenance cost.
In my assumptions I would construct a dam with walls which are 20 to 25meters high. The thickness would be one meter to make the walls strong. By use of materials such as cement, sand, bricks and metals. It’s possible to build walls that are strong enough to withhold the pressure both when there are low waves and high waves. I would construct a dam with parallel walls and between the two walls put springs for contraction and expansion when there’s pressure from the river. The walls would be built in such a way that the materials used would prevent eroding of the wall by the water. The materials used underneath will have to be different from the materials used to build the upper part of the wall.
Springs between the two parallel walls are meant for hydraulic purposes when the walls are pushed by the water. The springs prevent a rapid expansion and contraction of the walls which would cause the wall to collapse. The use of flexible materials at the lower part of the wall allows it to resist erosion against the soil and also handle the weight and the pressure of the water. The metal will be used to strengthen the walls although they are important in any construction.
Although the dam would be strong and use modern technology it would not be cost effective. It would require a lot of money for the materials being used like the cement and metals. Compared to the earlier day, the cost has gone much higher since the technique being used has changed and also the cost of materials has gone up too.
Work cited
Jansen, Robert B. Advanced Dam Engineering for Design, Construction, and Rehabilitation. New York: Van Nostrand Reinhold, 1988. Print.
The Embankment Dam: Held in Nottingham on 12-15 September 1990. London: Telford, 1991. Print.
Tumbare, M J. The Management of the Zambezi River Basin and Kariba Dam. Lusaka [Zambia: Bookworld Publishers, 2010. Print.
