Chicamba Real Dam (former Oliveira Salazar Dam)
Chimoio [Vila Pery, Mandigos], Manica, Mozambique
Equipment and Infrastructures
The idea for the dam basically originated in the textile project that the Sociedade Algodoeira de Portugal (Cotton Society, later named Sociedade Algodoeira de Fomento Colonial) intended to undertake at Chimoio, in order to meet the needs of electric power for the new industry. Hence the creation of the Sociedade Hidro-Eléctrica do Revué (SHER), in 1946, using State and private capital (according to decree no. 35.744, of 10.07, granting the use of the river and its tributaries, between 100 and 700 metres of quota), with the immediate construction of the Açude das Quedas (Weir of Falls) and the Mavudzi Power Station. This weir, which would be concluded in 1953, has an average height of eight metres and 230 metres of length, from where “a tunnel in reinforced concrete emerges, 2,000 metres long which crosses a small mound; the water flows along a pipe into a cliff that dominates the electric power station, from where it falls from an approximate height of 195 metres up to the turbines. [...] These turbines have an annual production capacity of 150,000,000 kwh. The power generation potential by the turbines would correspond, in the first stage, to 14.000 hp, and to 56.000 hp in the last stage” (Diário de Moçambique, Beira, 04.08.1957, pp. 1-12).
The second stage of the works included the construction of a new dam, on one of the gorges of the Revué (Chicamba Real), based on projects designed by the Gabinete de Estudos da Hidro-Eléctrica do Zêzere (Offices for the study of hydro-electric potential for Zêzere), and the enlargement of the Mavudzi Power Station, with the establishment of three new turbosets, of 12 megawatts each. The basic design of the new dam was essentially a “narrow vaulted arch of double curve”, with 814 feet long and 246 high regarding the foundations, with a retention capacity of 2,000,000 cubic metres of water. A power station, with turbosets of 23,000 horsepower, could provide a total output of 36 megawatts. Due to the depression of the land, a smaller levee was built as a complement.
According to decree 39.237 (06.06.1953), which granted it the establishment and exploration of substations and electric power transmission lines, the power station was immediately connected to Chimoio, after the construction of the Mavudzi Power Station; to the city of Beira, after the municipality had requested a loan to the Bank Nacional Ultramarino, with a work executed by the Società Anonima Elettrificazione, of Milan; and to Rhodesia, with the inauguration of the substation of Umtáli, on the 12th August 1957 (a ten-year agreement for the supply of electric power had been signed on the 27th October 1955, between SHER and Electricity Supply Commission, a Rhodesian institution that supervised the distribution of electric power in that colony). On the 20th June 1959, the two important undertakings were inaugurated. The Chicamba Real Dam was named after Oliveira Salazar and the Power Station of Mavudzi after Marcello Caetano.
The construction of a third dam at Tzata, roughly between the two other dams, was considered. The Mavudzi-Chicamba-Tzata system would be able to provide energy around 2,000,000 kilowatts/hour. Therefore, a general plan for use of the Revué basin (1959) was presented to the Ministry of Overseas Affairs, for approval.
The Chicamba Real Dam is therefore a magnificent construction, located about 30 km west of Chimoio, on the plateau of Manica. As mentioned before, it is a structure in reinforced concrete, with a curved surface (of two curves), in which two central pylons are bordered by two huge concrete walls. The dam (75 metres high, 194 metres in length, and ten metres thick at the base) was built within the context of the hydroelectric use of the Revué River for the production of energy for Beira Dondo and Chimoio, as well as for Rhodesia/Zimbabwe.