RICARDO AZOURY/OLHAR IMAGEMOverhead view of the Guandu River in the city of Piraí, state of Rio de Janeiro: a hydrological model guides decisions about water and land use.RICARDO AZOURY/OLHAR IMAGEM
Samuel Beskow, researcher and professor at the Federal University of Pelotas (UFPel) in the state of Rio Grande do Sul, has designed a computational model than can simulate the behavior of Brazil’s watersheds (also called drainage basins) and how they are affected by changes in land use. “The software provides supporting information for certain decisions, such as permission to use a river’s water for irrigation, the suitability of changes in land use, or reservoir establishment potential,” says Beskow, who has an undergraduate degree in agricultural engineering. Beskow developed the model — called the Lavras Simulation of Hydrology (Lash) — during his doctoral studies in hydrology and hydrological simulation at the Federal University of Lavras (Ufla), in the state of Minas Gerais, and at Purdue University in the United States. “The program enables users to outline irrigation, electricity generation, and navigation scenarios. It can even provide hydrological information to support the design of hydraulic projects, such as storm drains, channels, bridges, and dams,” says Beskow, who developed the project in partnership with researchers from three universities: Tocantins, Lavras, and Purdue.
The models currently used in Brazil are imported from the United States and Europe, which could result in limitations, according to the researcher. “Because of the climate and soil, among other characteristics, Brazil’s watersheds and their hydrological regimes can be considerably different from European and American ones,” says Beskow. Water resource monitoring in Brazil has been implemented mainly for drainage basins that are intensively used for hydroelectric power, irrigation, or urban supply purposes, and the available gauging data — including river water levels and flow rate measurements — are still insufficient to meet the country’s economic and environmental needs. “The major rivers are monitored, but there are countless smaller basins in agricultural areas where analysis is scarce,” he says.
Beskow’s Lash software was the 34th Bunge Foundation Award 2013 “Youth” category winner for the theme “Water resources and agriculture”. “The model is very important because it can be applied both to small watersheds and large ones,” says José Galizia Tundisi, professor emeritus from the University of São Paulo (USP), a graduate program advisor at the Federal University of São Carlos (UFSCar), and head of the global program for training water resource managers, offered by the Interacademy Panel (IAP). “It is a very advanced management tool,” says Tundisi, who is currently the municipal secretary for Sustainable Development, Science and Technology in the city of São Carlos, inland São Paulo State.
Independent analysis
The first version of Lash was completed in 2009, and the software is being used in rainfall and flow rate modeling research on Rio Grande Watershed sub-basins with hydroelectric generating potential. The Rio Grande Watershed drains the states of São Paulo and Minas Gerais. The program’s second version has been in development since 2011 and is now almost complete. The hydrological model has been enhanced for use by companies, watershed committees, water resource user associations, and the pertinent government institutions.
The program is divided into modules consisting of maps — which are managed in geographic information systems that characterize each watershed — and databases with meteorological information like temperature, wind speed, precipitation, soil type, and land use. Users can import and store data from different monitoring stations. “An interesting aspect is that each basin is divided into sub-basins, resulting in independent analyses of water budgets.” The model will also enable analyses on erosion and sediment transport along watercourses. “By cross-checking the data, we were able to analyze the susceptibility of a given basin to drought and flooding, rainfall events, and their effects, at intervals of hours or days,” says Beskow, who manages both the Hydrological Simulation and Data Processing Laboratory and the Water Resources graduate program at UFPel.
Lash enables users to identify the behavior of a watercourse and predict the volume of water that will be available during the dry or rainy seasons. “In addition to generating information, the model is an instrument that can be used in technical and economic feasibility studies for projects that require use of water resources from rivers.” Tundisi believes that Lash is an innovation from the research standpoint and as a management tool. “The program’s innovations include the drainage geoprocessing platform, for instance, which involves critical areas in the watersheds, not to mention the fact that it can be used for different regions of Brazil.”
Scientific articles
BESKOW, S., MELLO, C.R., NORTON, L.D., SILVA, A.M. Performance of a distributed semi-conceptual hydrological model under tropical watershed conditions. Catena. v. 86, n. 3, p. 160-71, 2011.
BESKOW, S.; NORTON, L.D.; MELLO, C.R. Hydrological prediction in a tropical watershed dominated by Oxisols using a distributed Hydrological model. Water Resources Management. v. 27, n. 2, p. 341-63. 2013.
