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hydrology

Waters under control

System for managing dams created in São Carlos attracts attention of companies from Brazil and abroad

MIGUEL BOYAYANSystem reconciles multiple uses of artificial reservoirs formed by hydroelectric power stations MIGUEL BOYAYAN

Artificially dammed waters, both at hydroelectric power stations and in the reservoirs for public water supply, now amount to some 7,500 cubic kilometers in the world, of which one thousand are concentrated on Brazilian territory. Such a volume needs constant monitoring, but there was a lack of an instrument that could be applied in reservoirs with different economic and social vocations, in the assessment of researcher José Galizia Tundisi, a retired professor from the University of São Paulo (USP) and a monitor for postgraduate studies at the Federal University of São Carlos (UFSCar) and at USP.

This finding was the starting point for the development of a system of management, which is now being used in barriers and dams and has awoken the interest of international entities. “The system was conceived to carry out an integrated management, because it reconciles the multiple uses of reservoirs, such as the generation of electricity, irrigation, navigation fishing, fish breeding, tourism and recreation”, says Tundisi. Furthermore, it also provides for scenarios that may occur in the long term and works with the whole river basin, and not just the dam. “Our proposal was to make a module having all these functions and capable of being adapted to the needs of each customer”, the researcher explains.

The study started in June 2000, at the Insitituto Internacional de Ecologia – International Ecology Institute (IIE), a private company that covers both basic and applied research, with the support of the Small Business Innovation Research Program (PIPE), financed by FAPESP. Two months afterwards, the IIE, which has Tundisi as one of its shareholders, was to close the first contract, with a company called Investco, to manage the water basin and the reservoir formed by the Luiz Eduardo Magalhães hydroelectric power station, also known as Lajeado, on the Tocantins River, in the amount of R$ 1.6 million, for a period of two years. Even without having been concluded, the project has started to attract international partnerships.

In December last year, the US Army Corps of Engineers (the largest dam management institution in the world), signed a cooperation agreement with the institute. “It provides for joint management projects, which will be applied all over the world, using our module”, says the researcher, a former president of the National Council for Scientific and Technological Development (CNPq). The institution came to know of the integrated management system in the course of a talk given by Tundisi, on August 13th 2002, in the Czech Republic, in the presence on the Army Corps’ representative, engineer Robert Kennedy. As soon as he got back to the United States, he phoned the IIE and proposed the joint work between the two institutions.

Another agreement, worth 49,000 euros (about R$ 180,000), intended for managing the Upper Tietê basins, was signed also at the end of last year, with the European Community, which is interested in creating management modules for South America. “To start with, this academic interest is trying to integrate Brazilian, French and Bolivian research in joint projects, using case studies in Brazil and in Bolivia”, the researcher explains. Professor Raphaèle Ducrot is in charge of the project, which enjoys the support of the Center for International Cooperation in Agricultural Research for Development (or Cirad, in its French acronym). This study also has the participation of USP and the State University of Campinas (Unicamp).

Another contract, with Hidroconsult, resulted in a strategic participation in a project carried out for the Basic Sanitation Company of the State of São Paulo (Sabesp), with suggestions to protect the water sources and to manage the water in the supply network. The IIE also provides consultancy services for Sabesp, in a project for transposing the waters of the Billings reservoir to the Guarapiranga reservoir. Other companies, responsible for the management of hydroelectric power stations, like AES – which is currently one of the controlling shareholders of the São Paulo Energy Company (Cesp), have now also shown interest in developing management modules.

Map of the ground
The system is made up of software with modules for hydrodynamic measurement (in which all the elements of circulation in the reservoir enter), on the transport of sediments and the quality of water. At the Lajeado reservoir, geologists have carried out a study of the ground, taking into consideration the various aptitudes for the various economic activities connected with the dam. “There we know which ground outside the dam is more or less sensitive to irrigation, and where there is going to be a discharge of sediments from the reservoir, leaving the place unsuitable for cultivation”, Tundisi says. All this information is put into an integrating module, which makes it possible to foresee long term scenarios. One of them evaluates, for example, what will happen with the reservoir if the population of the state of Tocantins reaches 10 million and the sewage is not properly treated.

One of the byproducts of the project is the Real Time Water Monitoring System (Smart), which resulted in a patent being filed with the National Institute for Industrial Property (INPI), financed by FAPESP’s Nucleus for the Patenting and Licensing of Technology (Nuplitec). Start is a station installed on a platform that stays anchored on the reservoir, transmitting data continuously, via radio, to the computer on the dam, which allows the operators to know the quality of the water. This data is retransmitted to the institute via the Internet.

Smart’s innovative conception is based on a mobile automated probe, developed by a grant holder on the project, biologist João Durval Arantes Júnior. The probe starts making a reading on the surface and goes down to a depth of 28 meters, taking readings at every 25 centimeters. After a 15-minute pause, it does the return trip, from the bottom to the surface. It stops once again for another half hour, and restarts the ritual, which makes it possible to find out, in real time, 11 parameters, such as the temperature of the water, its pH, oxygen dissolved, conductivity, turbulence, potential for oxide reduction, nutrients (nitrate, nitrite, ammonia and chloride) and chlorophyll.

“The idea of developing the system with a mobile probe arose as a result of the need for monitoring the parameters of the water at several depths”, says Durval Arantes. To start with, the proposal was to improve a monitoring system developed by researcher Le Coq Hung, from the National Center for Science and Technology of Vietnam. This system, which was shown by the Vietnamese scientist here in Brazil, collects information at a depth of only half a meter, from a boat. They went so far as to consider the possibility of a joint development to meet Brazilian needs, but Durval Arantes had the idea of moving the probe up and down in the water, to overcome the limitations of the equipment existing in the market. As the probe is an expensive component, the companies put a fixed unit at every 5 meters, until reaching a depth of 15 meters.

A climatological station was put on top of the platform, with sensors that measure the direction of the wind, the relative humidity of the air and the temperature. “Many probes use climatological data from outside the location. Ours makes it possible to make a correlation between, for example, the temperature of the air and that of the water, the speed and the direction of the wind, and the effects of the movement in the column of water”, Tundisi explains. According to the researcher, this association gives a complete vertical and dynamic vision of the system. A software gives the coordinates for the probe to carry out the scheduled research, and another interprets the data. With this information, associated to the information that will be made available in another program produced especially for each reservoir, it will be possible to adopt solutions that have to do with the whole water basin.

“With this project, we intend to develop a management process that integrates all these components, produces software, and from then on to carry out the training of managers at three levels: the hydroelectric power station, the city, and the state, for them to be able to take decisions, with the data available”, Tundisi reports. He quotes as an example an accident involving a truck transporting sulfuric acid. If the load falls into a river, the sensors are going to register the chemical change, and the operator will immediately be able to suspend the pumping of water.

High costs
The integrating module is the fruit of a joint development between the Instituto de Ecologia and the Innova Tecnology and Information, from São Paulo. Other companies are also taking part in this project: Hidromares, made up of researchers from the Oceanographic Institute, developed all the part referring to hydrodynamics. Investco built one of the platforms at Lajeado, and another is being built by a company from São Carlos, to be placed on the Broa reservoir, in Itirapina (SP), with a prototype of Smart. Taking part in the project, as advisors and consultants, are researchers from Brazil, Denmark, Spain and Sweden, who periodically read the reports or come to Brazil.

With his profound knowledge of fresh waters and over 30 years researching in the area, Tundisi says that the better the quality of the water, the greater the capacity of the local society for using the system for multiple uses. And he recalls that the preservation of the quality of the waters is a task that calls for considerable investments. The costs for treating deteriorated water are almost 13 times higher than when quality has been preserved. The treatment of 1,000 cubic meters of dirty water comes to US$ 25.00; and for clean water it is US$ 2.00.

The expenditure on the conservation of the turbines of the hydroelectric power station are also 20% more, when the water has an excess of algae and dirt. “The great goal of this project for the regions where it is being applied is to make it possible, through the handling of the managing system of water quality and for optimizing the multiple uses, to open up new possibilities for economic development”, reckons Tundisi.

In real time
The embryo of the project was a study made for the Corumbataí River, which supplies the city of Piracicaba. “The idea was to put a set of sensors into the river, before the treatment station”, says Tundisi. The operation of a water treatment station is carried out “blindfold”, according to the researcher. The operator has to plan the treatment the moment the water arrives at the station”, he says. If he receives the information in real time, he will be able to make decisions that are more suited to the circumstances.

According to Tundisi, the IIE was conceived as a company intended for classic, traditional, in the area of limnology (the study of fresh water and its organisms), and at the same time to serve as a consultancy. “The proposal is to transform existing knowledge into an innovation and a product, but it does not stop being a research institute”, says the researcher. Besides the PIPE project, the institute is working on a project from the Biota Program, also financed by FAPESP. The main intention of this project connected with Biota is to see what the relationship is between the quality of the water, pollution and the diversity of zooplankton in the state of São Paulo. These small animals, which live in suspension in the water and are part of the links in the food chain, may indicate a concentration of toxic substances in the environment.

The participation of the IIE in the program involved the study of 220 dams, in 22 basins of São Paulo, with the objective of having a map of the state from the point of view of the biodiversity of zooplankton, a specialty of researcher Takako Matsumura, who has been married 30 years with Tundisi and is a partner in the venture. “With this map, we have the ability to know today which are the areas where the biodiversity is greatest, and in what way they have been affected by pollution or otherwise”, says Takako. This information can be used in the PIPE project, following the institute’s concept of transferring the knowledge produced in basic science to a product that, by all indications, has a great field for application.

The project
Development for Decision Supporting Systems in the Management of Reservoirsfor Public Water Supply and for Hydroelectric Power Stations (nº 00/14482-7); Modality; Small Business Innovation Research Program (PIPE); Coordinator José Galizia Tundisi – International Ecology Institute; Investment R$ 180,777.67 and US$ 50,522.29

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