The Kariba hydroelectric project was built by IMPRESIT (later renamed IMPREGILO) between 1956-1960. Employer, the Central African Federation, consisting of South Rhodesia (Zimbabwe), North Rhodesia (Zambia) and Nyasaland (Malawi), then governed by Great Britain. Funding of the project by the World Bank. The dam was built at Kariba gorge, located halfway on the course of Zambezi river originating in Zambia and flowing into the Indian Ocean in Mozambique. The course of the river at Kariba marks the border between Zambia and Zimbabwe. With a length of 2754 km, the Zambezi River is the fourth longest in Africa after rivers Nile, Congo and Niger.The project consists of a double-curvature concrete dam, length at the crest 620 meters, height 128 meters, thickness at the base 24 m. at the top 14 m. Total volume of concrete cast on dam wall 975,000 cubic meters. Underground excavations on the right bank for power plant, penstocks, water outlets, etc. 600,000 cubic meters and 150,000 cubic meters of concrete. Generating capacity installed 700 MW. Additional generating capacity of 615 MW was installed by the construction of a power station on the left bank of the river in Zambia. The spillway comprise six hydraulic gates located 30 meters below maximum water level of the reservoir with discharge capacity of up to 9600 cubic meters of water per second. The dam formed the largest man made lake on earth, contains 185 billion cubic meters of water and covers an area of 5400 square km. It stretches over 220 km and has a width of up to 40 km. Kariba lake took 5 years to fill (1958-1963) to its maximum level. In OPERATION NOAH many species of wild life trapped on islands were saved from drowning as the lake water level grew, by transporting them to the shores of the lake. The dam was completed in June 1959 and the power plant started operating on January 1, 1960. The project was inaugurated by Queen Elizabeth, mother of today's Queen of England.
CLICK PHOTO TO WATCH VIDEO OF KARIBA DAM
During design and construction of Kariba dam, problems arose due to lack of long-term statistics on the seasonal flow of the Zambezi river. The maximum flow of the river during raining season at the catchment area could reach 18600 cubic meters per second, while during low season flow is reduced to 920 cubic meters per second. Delays and damages occurred, caused by exceptional flooding of the Zambezi River during 1957/58, the time of starting implemention of phase four of construction, i.e. laying the foundation of the dam inside the central cofferdam. The cofferdam was overflowed and flooded, thereby delaying foundation work of the dam.The video that I post, shows the flooded cofferdam and the dramatic increase in river flow. Fortunately, the concrete blocks already cast on the river bed towards the left bank, resisted the enormous pressure of the flooded river. Subsequently, the successful implementation of an accelerated working program during the years that followed, resulted not only in overcoming delays, but in completing the project six months ahead of schedule. A large number of technical and administrative staff, mostly Italians, were employed on the project as well as a great number of indigenous workers. A workforce of 5,000 Italians were employed on KARIBA , including those who resisted only a short while and then returned to Italy. The bed of the Zambezi river in Kariba lies at an altitude of only a few meters above sea level and for this reason climate at Kariba was very warm throughout the year. For me, it was the beginning of a marvelous "journey" that started at KARIBA and carried on with the same firm, building 4 dams including the largest rock fill dam in the world, Tarbela, built on the Indus River in Pakistan between 1968 and 1974. Outstanding achievements in various countries of the world, in collaboration with the wonderful people of IMPREGILO, still world leader in construction of hydroelectric plants around the globe and other major projects such as ports, roadworks, airports, widening of the Panama Canal, etc. The same company has just completed the imposing CULTURAL CENTER OF ATHENS (National Library and Opera) at the PHALIRON DELTA, at a cost of over half billion dollars, donated to the people of Greece by Stavros Niarchos Foundation.
British Pathe’ newsreel concerning flooding of the Zambezi river in 1958 affecting construction of KARIBA DAM.
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