water resources management in brazil water resources management in brazil water resources management is a key element of brazil's strategy to promote sustainable growth and a more equitable and inclusive society. brazil's achievements over the past 70 years have been closely linked to the development of hydraulic infrastructure for hydroelectric power generation and just recently to the development of irrigation infrastructure, especially in the northeast region. not to be confused with water supply and sanitation in brazil or irrigation in brazil. water resources management in brazilwithdrawals by sector 2000/2001 domestic: 12% agriculture: 80% industry: 8% renewable water resources8,233 km3surface water produced internally5,418 km3groundwater recharge1,874 km3overlap shared by surface water and groundwater1,874 km3renewable water resources per capita43,028 m3/yearwetland designated as ramsar sites6.4 million hahydropower generation81% two challenges in water resources management stand out for their enormous social impacts: (i) unreliable access to water with a strong adverse impact on the living and health standards of the rural populations in the northeast where two million households, most in extreme poverty, live, and (ii) water pollution in and near large urban centers, which compromises poor populations' health, creates an environmental damage, and increases the cost of water treatment for downstream users. water management history and recent development as in many other countries, water resources management in brazil has historically relied upon heavy investment on hydraulic infrastructure. from building the first hydropower facility in 1901 until the mid-1970s, hydropower has been the main focus of water resources management. in 1934, after several modifications introduced to the first 1907 draft, the water code was approved. the water code was the first legislation for water resources management in brazil, and was applied for more than 60 years. the water code ensured the free use of any water for basic life necessities and permitted everyone to use any public water while complying with administrative regulations. some of its provisions, such as the polluter pays principle, were introduced long before this principle became globally recognized as a good practice. the intention of reforming brazil's water resources management system began to shape during the 1970s when other water users challenged the priority given to hydropower. different initiatives and institutions for water management were established by the federal government and states such as são paulo and ceara. the constitutional reform of 1988 was the first step in the creation of a national water law, whose responsibility was given to the federal government. the reformed constitution also established a distinction between federally controlled water, for rivers across state boundaries, and state-controlled water, for rivers and groundwater that remained completely within state boundaries. based on this new responsibility, the states began to implement their own water resources management systems. são paulo pioneered this process in 1991 (see water management in the metropolitan region of são paulo). today 25 of brazil's 26 states and the federal district have adopted legislation to modernize water resource management (see states of brazil). after negotiating for six years, the federal government approved the 1997 national water law (no. 9433) aimed at incorporating modern water resources management principles and instruments into brazil's water resources management system. a national water authority was created in 2000 aimed at implementing the national water law. numerous local, regional, and national initiatives, public and private bodies, and technical, scientific, and professional associations also play a role in brazil's water resources management system. water resource base surface and ground water resources brazil has always been considered a country rich in water. it is estimated that about 12% of the world's surface water resources are located in the country. in 2007, per capita water availability reached 43,027 m3 per year, above the world average of 8,209 m3 per capita in the same year. however, this impressive average masks an extremely uneven distribution of water resources among regions. amazon river basin the amazon river basin alone, which covers 48% of the country's territory, accounts for 75% of brazil's freshwater resources but has only 4% of its population. the most dramatic departure from abundance can be found in the northeast region, which includes most of the country's semi-arid region. accounting for 18% of brazil's territory and about 28% of its population, the northeast region has only 5% of the country's water resources and is subject to recurrent, severe droughts, harvest failures, and food shortages. with 73% of the country's population, 11% of its territory, and about 10% of its water resources, the southeast is the heart of brazil's industrial economy and also has the highest agricultural production brazil has three river basins (the amazon, tocantins, and são francisco), and two basin complexes, the plata river which has three brazilian sub-basins (paraná, upper paraguay, and uruguay), and the remaining rivers flowing into the atlantic which are divided into several basins. the amazon and the tocantins-araguaia basins in the north account for 56 percent of brazil's total drainage area. the amazon river, the world's largest river in volume of water and second longest after the nile, is navigable by ocean steamers as far as iquitos in peru. the são francisco river is the largest river entirely within brazil, flowing for over 1,609 km northward before it turns eastward into the atlantic. the last 277 km of the lower river is navigable for ocean-going ships. the paraná-paraguay river system drains the southwestern portion of the state of minas gerais. brazil's two southernmost states partially drain into the uruguay river which flows into the plata river. the inflow of the amazon to brazil is 1.9 bcm per year, so that the total surface water resources in the country reach, on average, 8.2 bcm per year basin name surface area (1000 km2) precipitation (mm/year) evapotranspiration (mm/year) amazon basin 3935 8735.7 4918.8 tocantins-araguaia 757 1256.6 884.2 north and northeast 1029 1533.0 1239.6 san francisco 634 580.7 490.7 east atlantic 634 321.0 246.2 parana-paraguay 1245 2139.9 1656.7 uruguay 178 278.9 148.1 southeast atlantic 224 312.3 176.7 total 8547 15158.1 9761.0 source: fao the volume of stored groundwater in brazil less than 1,000 m deep and with good quality for human uses is estimated at 112,000 km3, with highly variable extraction rates. in brazil, groundwater is used in rural areas for domestic water supply and irrigation on a moderate scale. estimates indicate that approximately 300,000 wells are being used, and over 10,000 more are drilled every year. on a large scale, groundwater is beginning to be used in areas where the surface water sources are scarce, where they are heavily used, or where their use is problematic due to heavy water pollution (central and southern brazil). storage capacity and infrastructure the varies by regions. the northeastern state of ceará, with 7,227 dams, has a cumulative maximum storage capacity of 11 billion cubic meters. however, losses from surface evaporation are equivalent to a large part of the annual inflow to the reservoirs due to arid climate conditions and shallow reservoirs the amazon river is extremely wide for most of its length, so most of the dams are located on its tributaries. the tucurui dam, located on the tocantins river in the northeastern region, has a capacity of 110 bcm and a generating capacity of 8,000 mw. water quality sewage is a major cause of water pollution in brazil, a major problem that undermines quality of life, health, and economic development in large metropolitan areas and has a disproportionate impact on the poor in the slums surrounding brazil's largest cities. according to the 2000 national survey of sanitary conditions (pnsb), less than 10% of the wastewater produced in urban areas is treated. the 2000 pnsb was the latest survey of water supply for human consumption and wastewater collection and treatment conducted nationwide. water quality management is also undertaken by the states, although the quality of their water monitoring systems and surveys varies widely. in 2006, only nine brazilian states had water quality monitoring systems that were rated as excellent or very good; five had good or fair systems; and thirteen had weak systems. the southeastern state of são paulo, with a monitoring system considered very good, registered in its latest study high microbiological indexes indicative of pollution from domestic sewage both upstream and downstream in the bairro da serra river and even higher rated from two its main tributary streams. water resources management by sector water supply and sanitation main article: water supply and sanitation in brazil domestic consumption accounts for 21% of water withdrawals in brazil. the water and sanitation sector in brazil has proved to be resilient and resourceful, despite tremendous challenges and persistent inequalities in the sector. much has been achieved in the past decades, including a sustained improvement in efficiency and access. access to improved water supply increased from 93 % in 1990 to 90% in 2004, and access to improved sanitation increased from 71% to 75%. irrigation and drainage about 61% of all water withdrawal in brazil is used for irrigation, which is lower than the average water withdrawal for irrigation in latin america, 71%. the irrigated area in 1998 was 2.8 million ha, which represents 5.7% of the cultivated area. the irrigation potential of brazil is estimated at 29.3 million ha, including only areas where irrigation can be developed and excluding areas of high ecological value in the northern region (amazonas and tocantins basins). the ineffective irrigation has generated salinization and drainage problems in 15,000 ha, mostly in the northeast (of a total irrigated area of 736,000 hectares), jeopardizing these lands' productivity. hydropower panoramic view of the itaipu dam, with the spillways (closed at the time of the photo) on the left access to electricity has increased from fewer than 500 kilowatt hours (kw·h) per capita in 1970 to more than 2,000 kw·h per capita in 2000. these results have been achieved mainly through the development of hydropower, which currently accounts for 81% of brazil's installed capacity (69 gigawatts out of a total of 79). brazil also has the largest hydroelectric power plant in operation in the world, the itaipú dam which was built from 1975 to 1991, in a joint development on the paraná river. its 18 generating units add up to a total production capacity of 12,600 mw (megawatts) and a reliable output of 75 million mwh a year, providing 25% of the energy supply in brazil and 78% in paraguay (in 1995). aquatic ecosystems brazil has more freshwater fish species than any other country on earth, with the world's largest river basin, the amazon, and the world's largest tropical floodplain, the pantanal. in the amazon river alone, there are an estimated 2,000 species of fish, more than all in north america. yellow-billed spoonbill the pantanal covers at least 140,000 square kilometers of land, over four times the size of the florida everglades in north america. there are an estimated 700 species of birds, including spoonbills, and 26 species of parrots, including the endangered hyacinth macaw. the pantanal is also home to the capybara, the world's largest rodent. fish thrive in this wetland environment (over 260 species have been noted). illegal poaching, deforestation, overfishing, pollution from human sewage, agricultural pesticides, and metal pollutants are taking an increasing environmental toll on the area. in 2007, brazil had identified nine sites that fulfill criteria for wetlands of international importance according to the ramsar convention, seven of which are mainland wetlands. they include three national parks: one in the pantanal (parque nacional do pantanal mato-grossense); one in the araguaia (parque nacional do araguaia); and one in the peixe lagoon (parque nacional da lagoa do peixe); two environmental protection areas in the state of maranhão (área de proteção ambiental da baixada maranhense and the área de proteção ambiental das reentrâncias maranhenses); a private wetlands reserve in the pantanal (reserva particular do patrimônio natural sesc pantanal); and the mamirauá sustainable development reserve (reserva de desenvolvimento sustentável mamirauá). in 2006, the government of brazil approved its first freshwater management plan, assuring that aquatic biodiversity will be an important aspect of freshwater planning for the entire country. with this plan, brazil's government explicitly made biodiversity a part of the decision-making process for the use of the country's freshwater resources. legal and institutional framework international legal framework brazil has signed numerous treaties with neighboring countries, aimed at promoting sustainable use of shared water resources. the treaty of the rio de la plata entered into force