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Engineering

The waters are going to roll

Transposition of the River São Francisco divides opinions and stirs up polemics between government and researchers

Since the times of the Empire, Brazil has been seeking a solution to minimize the effects of the drought in the northeastern semi-arid region. In 1847, D. Pedro II was even willing to sell the jewels of the Crown to take the waters of the River São Francisco to the region. His intention was not consummated, and the jewels were preserved.  In the 20th century, the transposition of the waters of the river was cogitated another three times, in 1980, 1990 and 2000.  The lack of funds and of consensus, however, made all the projects unviable. The first proposal of this century – and no less polemical – is the Project for Integrating the River São Francisco with the Water Basins of the Northern part of the Northeast, from the Ministry of National Integration.

The goal of the project is to ensure the supply of water for multiple uses for 12 million persons. It provides for the construction of two concrete-lined canals, 720 kilometers in length, 25 meters in width and 5 meters in depth, by means of which 26 cubic meters a second will be captured, continuously, of the waters of the River São Francisco, and transported to the region of the drought. When the Sobradinho reservoir is full, the volume captured can reach 114 cubic meters. The average flow will be 63.5 cubic meters per second, and the work’s total transport capacity will be 127 cubic meters per second.

All along the route, nine pumping stations will be constructed to overcome differences in level of up to 160 meters in height, besides 27 aqueducts, 8 tunnels and 35 small-sized reservoirs. The first stretch of this monumental work that the federal government wants to start before the end of this year is budgeted at R$ 4.5 billion. “The area of the project covers 37% of the population of the drought polygon”, is the justification given by João Urbano Cagnin, the project’s technical coordinator at the Ministry of National Integration.

“Bringing water to the ocean?”
The project began to be drawn up in 2003, and, since then, it has advanced more than any other in the last 150 years: the calls for tender for the first stretch of the work were published on May 13, and the more than 30 interested contractors have until June 28 to present their proposals.

But the idea that the transposition will effectively reduce the effects of the drought in the northeastern semi-arid region is far from being a political or technical consensus.

Opposition to the project is uniting people ranging from governors of states ‘donating’ and ‘receiving’ water – since they are responsible for the bill for the works that link the channels to the sanitation network – to scientists and environmentalists, including nongovernmental organizations. It is particularly strong amongst the members of the Committee of the São Francisco River Basin (CBHSF). There are prospects for the preliminary environmental license granted by the Brazilian Institute for the Environment and Renewable Natural Resources (Ibama), at the beginning of May, and the tender process under way being contested in the courts, by means of civil lawsuits.

Political disputes aside, the critics regard the projects as economically unviable and socially unjust. They argue that a water deficit does not exist in the Northern part of the Northeast to justify a project of this magnitude. “The Northeast has water. There are 70 thousand dams with something like 37 billion cubic meters of water. It is the largest volume of dammed up water in the world”, says João Suassuna, from the Joaquim Nabuco Foundation.

Half of this water, he says, is in the Castanhão dam, in Ceará, which meets the demand from Fortaleza and from the population of the lower Jaguaribe, which will be supplied with water captured in Cabrobó , in the state of Pernambuco and transported along the northern axis of the project to Ceará. “Why carry even more water to this dam?”, he inquires. In his assessment, what is lacking is a policy for the use of water.

The transposition project ‘is like bring water to the ocean’, in the assessment of João Abner, a professor from the area of water resources of the Federal University of Rio Grande do Norte (UFRGN). He uses the example of two states from the Septentrional Northeast to contest the thesis of water deficit. Ceará has 7.5 million inhabitants, 35 mega-dams and a potential supply of 215 cubic meters per second for a current consumption of 54 cubic meters per second. D. Pedro’s dream has already been realized in Ceará, with the construction of the Castanhão dam, he says.

Rio Grande do Norte, with a population of 2.7 million persons, enjoys a guaranteed flow of 70 cubic meters per second, to meet a demand of 33 cubic meters a second. “Even Paraíba, the state least endowed with water resources in the region, shows a significant surplus: 32 cubic meters per second, for a demand of 21 cubic meters a second”, Abner explains.

In his assessment, what is lacking for the Northern part of the Northeast is a policy for allocating water through aqueducts, like the one carried out in Rio Grande do Norte. The state used the resources from the privatization of its electricity company to invest R$ 250 million in over a thousand kilometers of aqueducts that supply half the population. “They take the water from the coast and from the Armando Ribeiro Gonçalves dam, on the River Piranha-Açu, to the semi-arid region”, he says.

The technical coordinator of the project rebuts the criticisms about the availability of water in the Northeast. “Of the 70 thousand dams, only a hundred are worthwhile. The others are great evaporators of water”, he warrants. “And the large dams cannot be used, because water has to be kept for the future, and they are impaired: they lose 2 meters of water a year, from evaporation”, Cagnin argues. “Of the 18 billion cubic meters of water available in Ceará, for example, only 20% can be used. That is to say, there are dams but not water?”

The dams of the Northern part of the Northeast accumulate the maximum of water in the rainy season, during three or four months a year. Even when they are full, the use of the water is controlled in such a way as to guarantee supply, even in the case of prolonged drought. The integration of these dams with a permanent source of water of great volume – with the water that will be transposed – will make it possible for the water stored in the dams to be released in larger proportions for productive activities.  The guarantee of supply will attract investments, create more jobs, and increase the income of the population. “If we want to give the Northeast a new opportunity, we have to guarantee water.”

The water accumulated in the reservoirs and dams will have multiple uses, including economic ones. Along the two canals, the project provides for the installation of points for capturing water and watering places to meet the demand from the population of the nearby areas and to make irrigated farming by small producers viable.

But the main focus of the project is to stimulate urban development. “It’s not only water for drinking, but for living. The project is going to put water in the dams and supply it to the cities”, the technical coordinator of the project emphasizes. “It isn’t water for the population that is spread out”, he insists. For this population, the government is implementing the construction of 1 million cisterns, a R$ 1.5 billion project, one fourth of the amount foreseen in the transposition. “The cistern produces 1 cubic meter of water per second, and the transposition, almost 70 cubic meters per second”, he compares.
The economic use of the water is strongly contested. “The government wants water for agribusiness”, sums up Suassuna, from the Joaquim Nabuco Foundation. “It’s water for agribusiness”, repeats Abner, from UFRGN. “Is the displaced water going to reach the producer?”, inquires Luciano Pagnucci Queiroz, a researcher from the National Semi-Arid Institute.

Treating water as an “economic asset brings about the exclusion of a large part of the population”, warns the manifest Foreseeable risks, incalculable consequences, signed at the end of last year by 250 associations, trade entities and nongovernmental organizations and made public with the intention of barring the approval of the project.

This, incidentally, was one of the reasons why the Committee of the São Francisco River Basin rejected the transposition project. After five public consultations in cities of the region, the committee approved the external use of the waters from the river “only for supplying humans and watering animals” and in situations of proven scarcity, according to Geraldo José dos Santos, a technical advisor to the committee.

In the case of the eastern axis of the project – which leaves the Itaparica dam, on the border between Pernambuco and Bahia, close to Nova Petrolândia, and goes on until the River Paraíba–, the water will be transported to the  agreste and can be used for subsistence. “But in the northern axis, the use of the water will be of an essentially economic nature. A small portion of this water, in an amount of no more than 26 cubic meters per second, will be intended for human and animal consumption”, Souza foresees.

For Cagnin, the polemics surrounding the use of the water of the São Francisco is a result of an old vision of the Northeast, of an economy “built on the hooves of the cattle and that was responsible for its sparse settlement”. Today, he continues, Brazil has the most populous semi-arid of the world, has modernized itself, become more urban, come out of the rural culture. That is why it needs more water.

Energy for the future
The critics are also afraid that the transposition may jeopardize the future demand for electricity, calculated at about 6% a year, for a 4% growth of the Gross Domestic Product (GDP). The River São Francisco is responsible for generating over 95% of the Northeast’s electricity, almost entirely produced by São Francisco Hydroelectric Company (Chesf).

The Environmental Impact Report (Rima) estimates that the use of the waters from the river, in the volumes estimated by the project, should bring about a loss of 137 MWh/h in power for the power stations, that is to say, 2.4% of the average power generated by Chesf, as from 2025. This loss, also according to the Rima, can be compensated for with the production generated by the thermal power plants that are being installed in the region, or by hydroelectric power plants located in other basins, by means of the National Interlinked System.

“Chesf generates 5,600 MW a year on average, and the project is going to consume 1% of this power, and in the medium term”, says Cagnin. He also notes that the electrical system in Brazil is interlinked, and that the Northeast already receives 20% of the power generated at the Tucuruí hydroelectric plant. “In the future, 15 years from now, over half the power will come from outside the São Francisco.”

Between the critics and the defendants of the project, there are also apparently some divergences in calculations. Minister Ciro Gomes has been saying that the transposition will use only 1% of the volume discharged into the sea. But the Committee of the São Francisco Basin contests this. The 1% calculation is inadequate, since it takes for its basis the river’s historical average flow, without taking into consideration that part of this water is no longer available. In an official note, the committee observes that, to guarantee minimum conditions for the river at the estuary, the Water Resources Plan set a maximum flow of 360 cubic meters a second, of which only 269 cubic meters a second are left. Calculated on this balance, the transposition would in fact take away between 24% of the river’s water, at the average flow, and 47%, at the maximum flow.

The cost of the water transported, estimated at R$ 0.11, is also generating polemics. In the rural area today, no charge is made for raw water. The users only pay for the cost of pumping from the source of supply to the agricultural area. “With the transposition, they are going to pay more dearly for the use of the water, five or six times more than the amounts practiced in the region”, Abner reckons.

Cagnin clarifies that this will not be the price of the water used for irrigation or in the rural areas. He observes that the water will have a multiple use, and that this amount, R$ 0.11, will be paid by the urban industrial consumer, in exchange for a guaranteed supply, which represents in increase of 10% over the current fee. Outside the urban areas, the price will be calculated by offsetting, on the basis of a crossed subsidy.

The worries do not stop there. Queiroz, from the National Semi-Arid Institute, for example, is afraid that, if the work is not carried out well, the canals will also do a transposition of the biota (the set of forms of life of a given environment). This risk is amongst the 22 negative impacts pointed about by Rima. To minimize it, it is planned to monitor the mixture of the biotas in the donating and receiving basins, to install filters at the points where water is taken from the River São Francisco, and to run subprograms for monitoring the fish, the quality of the water, and for geological studies in the two channels.

Public consultation
The Ministry of National Integration wants to allocate R$ 2 billion to the project in 2006. Besides trying to prevent the work from starting in the courts – and promising to obstruct the voting of the Law on Budgetary Guidelines, should the government not give ground in its forecast of spending–, the oppositionists want to let the Brazilian population have the last word on the project. Deputy Luiz Carreira (PFL/BA) presented to the table of the Chamber a legislative decree proposing a plebiscite on the transposition of the River São Francisco for the first Sunday in October 2006. The proposal is running its course in the Environment Commission. “It’s not just any engineering work. It’s a project for economic development”, the deputy argues.

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