Amazon River CE397 – Transboundary Water Resources Spring 2008 Eusebio Ingol Current Situation Amazon River basin has a surface around 6.2 million km2 which is shared by Peru, Colombia, Brazil, Venezuela, Surinam, and Guyana. From this total area, the 58 % is located in the Brazilian part. Amazon River is one of the most important rivers in the world, with an average discharge of 210,000 m3 per second; being the largest in the world’s rivers in terms of the volume, six times that the Congo River. It has more 1,100 tributaries; 17 of them present lengths over 1,000 km such Maranon, Purus, Madeira, Negro, Tapajos, Madre de Dios, Huallaga, between others. The origin of the Amazon River is in the Peruvian Andes. Since its source until mouth in the Atlantic Ocean from Brazil, it has a length of 6500 km. Figure 1 Location of the Amazon river Basin The wide of the main river oscillate from 1.5 km to 10 km in normal periods. However, in rainy season, the width can reach up 40 km with an average depth of 40 m. Water Resources The water resources provided for the Amazon River represent the 20% of the available freshwater in the world. The flow in the Amazon River increases apart from November to June, from this month starts to fall until October; being the lowest flow period in August and September while the highest occurs from January to May. The behavior is different in the Negro River (one of the most important tributaries of Amazon River) where the rain period starts in March. Similarly, in the Madeira river, the increase in flow can be noted a part from January; which starts to fall two months earlier that the main river. In figure 2 is shown the variation of the monthly precipitation in South America, in which include the Amazon Basin. The annual average precipitation for Amazon region is over 2000 mm.Figure 2 variation of the precipitation in South America for the 2001. (Source NASA) Amazon region is characterized for having low densities of population, with problems of contamination which causes are related to wastewater treatment in located cities such as Belen and Manaus in Brazil, and Iquitos in Peru, mineral extraction (gold miners). In the Amazon basin, the water resources are related to the fishing, navigation, and hydroelectric power. The potential use of the hydropower in Amazon region represents the 40 percent of total energy in Brazil. Moreover, for generating energy in the region, dams were built. The Tucurí dam on the Tocantins River in Pará state, the Balbina dam on the Uatumã River in Amazonas state, and Samuel Dam on the Jamari River in Rondônia state − which were built to supply electricity both for the cities of the Amazon region Manaus, Belen and Porto Velho, respectively. Environmental problems The main environmental problems in the transboudary water resources in the Amazon River basin are related fundamentally to the following issues: Deforestation in the basin causes erosion and soil loss, sedimentation in the rivers, unbalance in the vital ecosystems. Expansion of the urbanization; destruction of the fragile ecosystems. Two largest cities in river basin can be mentioned: Manaus and Belen in Brazil (over 1.5 million). Iquitos in Peru, Leticia in Colombia, and Lago Agrio in Ecuador. Water pollution and quality degradation. Use of agriculture pesticides, inadequate wastewater treatment from populated areas, contamination of the rivers by mercury (This product is used by gold miners located mostly in the middle and upper basin) Change in the hydrologic cycle which is related with climate change. In Brazil, over 60 percent of deforestation in the Amazon basin results from the Cattle ranches; while the 33 percent corresponds to the agriculture in small scale. This problem causes erosion; in that sense, more than 1,000 tons/km2 /year of sediment flowing toward the Atlantic Ocean. In general, 600 to 800 million tons of sediment per year are transported by the Amazon River. Treaties and projects The main treaty signed in the Amazon River basin was the following Treaty cooperation organization (OTCA) among the countries of the Amazon basin Brazil, Peru, Bolivia, Colombia, Ecuador, Guyana, Surinam, and Venezuela. 07/03/1978.In this treaty, the Contracting countries agree to carry out joint actions and efforts to promote the harmonious development of their respective Amazonian territories in such a way that these joint actions produce equitable and mutually beneficial results; as such as the environment preservation and the conservation and rational utilization of the natural resources. The principal objective of this agreement is to achieve an adequate use of the natural and energetic resources. This treaty was instable during two decades; which determined that it was re launched in 1998. Likewise, the following treaties of commerce and navigation were signed: Treaty of commerce and river navigation between Brazil and Colombia August 21, 1908. Treaty of commerce and river navigation between Brazil and Bolivia August 12, 1910 Treaty of delimitation, commerce and navigation between Brazil y Peru. Treaty 1918 ratified in 1927. In the Amazon River basin, several projects related to Environmental and water resources have been carried out. For instance, the project GEF Amazon. OTCA/GEF/PNUMA/OEA. Integrated and sustainable management of transboundary water resources in the Amazon River basin. United Nations Environment. Oct 2005. The main objective of this project is strengthen the institutional framework for planning and carry out activities for the protection and integrated management of the land and water resources in a coordinated and coherent manner in the Amazon River basin, considering the climatic change experienced in the basin. In addition, there are some projects leaded by the World Bank such as integrated management of aquatic resources in the Amazon region project (AQUABIO), Amazon region protected areas project (ARPA) (2002), Pilot program to conserve the Brazilian rainforest (PPG7) (1992), Pilot Program floodplain resources management project (PROVERZEA) 1999-2007 Required reading: Paul E. Little. Abundance is Abundance is not enough. Water‐related conflict in the Amazon River Basin. University of Brasilia. Brazil, 2003. Pages. 4‐12 http://www.unb.br/ics/dan/Serie337empdf.pdf Supplementary reading: Takuji Kulbota. "Global precipitation map using satellite borne Microwave radiometers."CREST, Jepan Science and Technology