Position Papers
Itaipu: a reference in dam safety
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Itaipu is publicly reinforcing its commitment to the safety of its dam, reiterating the latest assessment of the Board of Civil Consultants – an international board of engineers with well-known safety in dam safety, convened by the binational company every four years to analyze the performance of structures. According to the group's verdict, announced on November 30, 2018, the extensive instrumentation, full-time monitoring and permanent dedication of engineers and technicians of the company's own staff make the Itaipu dam one of the safest in the world.

"We can safely say that, in these 36 years since the filling of the reservoir, the work of Itaipu professionals focused on dam safety continues to guarantee a fully safe structure under control and ready for the new challenges of the plant, such as technological upgrading and the possible expansion of installed capacity”, said the coordinator of the Board, the Italian engineer Corrado Piasentin.

The Itaipu teams strictly comply with the Board's determinations. The dam safety in the company is also endorsed by Eletrobras, whose website provides an area with extensive material on the subject, including news, technical information, legislation and frequently asked questions.

Itaipu, whose Brazilian half is part of the Eletrobras holding, is cited as an example: "Eletrobras companies adopt the best practices related to the safety of dams in electric power generation and are considered a national and international reference in this area, with emphasis on Itaipu Binational, which had a decisive role in the creation of the Brazilian Law No. 12,334/2010 (National Policy for the Safety of Dams)."

Tailings dam x hydroelectric dam

There are considerable differences between hydroelectric dams, such as Itaipu, and tailings dams.

A tailings dam is a land structure built to store mining waste, forming a reservoir with solid substances and water, in the form of mud, resulted from ore beneficiation processes.  Storage of these tailings is necessary to avoid environmental damage. It is constructed from a dike formed by clayey materials or compacted rocks, with elevations made to increase the storage capacity.

A hydropower dam has the purpose of damming and storing water, raw material for the production of energy, and obtaining the necessary difference to spin the turbines of the generating units. The one of Itaipu is made of concrete, rockfill (a sea-wall of large rocks) and earth. It has an extension of 7,919 meters and a maximum height of 196 meters, equivalent to a 65-storey building. It consumed 12.3 million cubic meters of concrete. The amount of used iron and steel would allow the construction of 380 Eiffel Towers.

The safety of the dam at Itaipu

The superlative dimensions and strategic importance of the 14,000 MW installed power plant for Brazil and Paraguay have made dam safety one of Itaipu's priorities, from the design phase to the completion and maintenance of the mega-work. Monitoring dam safety began even before the first generating unit of the dam was installed and remains highly relevant - not only to maintain and extend the life of the dam, but especially to protect life and property in the vicinity of the dam.

The work mobilizes several sectors of the Technical Directorate of Itaipu, mainly of the administrations of Works and Engineering. They are technicians and engineers fully dedicated to dam safety. They visually inspect the structure, check for possible oscillations, technically analyze field data, provide repairs when necessary, and perform the Civil Advisory Board's determinations – among many other activities.

Almost 3,000 instruments scattered throughout the structure – some of them electronic and monitored in real time – make Itaipu one of the planet's best-equipped plants for dam safety. Despite the different shapes, sizes and ends, the instruments converge on the ultimate goal: providing information to diagnose the behavior of the dam before the action of time and the enormous amount of water that it has to endure.

During and after the construction of the hydroelectric plant, the deepening of the studies motivated the emergence of auxiliary structures of great contribution to Itaipu Binational, such as the Itaipu Concrete Technology Laboratory (LTCI), installed in the plant, and the Center for Advanced Studies in Safety (Ceasb), at the Itaipu Technological Park (PTI). Both collaborate in dam safety activities at Itaipu and also bring to society, especially to the academic community, the knowledge acquired in almost four decades of constant care with the hydroelectric structure.

Engineers from several countries come to Itaipu to get a closer look at this work, which is now internationally recognized and has made the plant also a reference to dam safety. Among them, the Chinese of the Three Gorges plant, the largest power plant installed in the world.

Recognizing the importance of dam safety, Itaipu will continue to invest constantly in capacity building and equipment to keep its structure fully safe and the population calm.