FLOODS AND SOCIOENVIRONMENTAL VULNERABILITY IN THE MUNICIPALITY OF ATIBAIA, SP – BRAZIL ENCHENTES E VULNERABILIDADE SOCIOAMBIENTAL NO MUNICÍPIO DE ATIBAIA, SP – BRASIL

The occurrence of floods is increasingly common in urbanized areas and creates a multitude of hazards and socioenvironmental vulnerabilities. The municipality of Atibaia in the state of São Paulo (Brazil), which was flooded in the years of 2002, 2009, 02010, and 2011, had some of its socioenvironmental vulnerabilities analyzed. Thus, this paper aims to analyze the occurrence of floods in Atibaia from 2000 to 2012. The methodological approach involved a review of the scientific literature, as well as the collection of secondary data from various governmental and non-governmental organizations working in this region. Key-Words: Floods. Vulnerability. Urban Areas. Atibaia. FLOODS AND SOCIOENVIRONMENTAL VULNERABILITY IN THE MUNICIPALITY OF ATIBAIA, SP – BRAZIL Revista Meio Ambiente e Sustentabilidade | vol.9, n.4, | jul dez 2015 101 RESUMO A ocorrência de enchentes e inundações é cada vez mais frequente, sobretudo em áreas urbanizadas, criando uma infinidade de perigos e vulnerabilidades socioambientais. Algumas dessas vulnerabilidades foram examinadas com o exemplo de Atibaia, município do estado de São Paulo (Brasil), que foi submetido a inundações repetidas entre 2002, 2009, 2010 e 2011. Desta forma, o objetivo deste artigo é analisar a ocorrência de enchentes em Atibaia, no período de 2000 a 2012. A metodologia envolveu revisão da literatura científica, bem como a coleta de dados secundários de várias organizações governamentais e não-governamentais atuantes na região. Palavras-chave: Inundações. Vulnerabilidade. Áreas urbanas. Atibaia.


INTRODUCTION
Technological advances have significantly changed social dynamics. While improving some aspects of life, e.g. facilitating access to services and consumer goods, such advances lead to a more comfortable and healthier life. They also promote changes in social and cultural habits. Due to the population growth, these changes are a driving force for the urbanization of cities. As a result, it increased the production levels demand and the level of energy that led to increased levels of waste. Along with other factors, these changes affect the quality and availability of natural resources (HOGAN; MARANDOLA,200), that generate social tensions and increase companies' exposure to multiple risks and vulnerabilities.
The constant and progressive pressure on water resources, due to the growth of cities, sometimes fail to respect the individual geological conditions and the natural course of rivers is important in this context. For instance, roads construction on river banks lead to natural problems, such as floods, which are later "solved" by channeling rivers (AMARAL; RAJA, 2012; TOMINAGA; SANTORO; AMARAL, 2012).
The urbanization does not only alter the superficial landscape of an area, but also the hydrological dynamics of river basins, including changes to the watercourses.
As cities are urbanized surfaces they are sealed and there are high peak flows, which increase the flow capacity through pipelines and canals. Unprotected river surfaces lead to a higher production of sediments and these elevated levels of solid waste can be partially responsible for floods (TUCCI, 2008). Along with the vegetation, the soil should in theory, facilitate the flow of water through suction, but in fact, it hinders the ability of water to infiltrate the ground in some areas, and making it virtually impossible in others. This ultimately favors the runoff, interferes with the watercourses and modifies the behavior of the surface area (AMARAL; RIBEIRO, 2012;TAVARES;PINHEIRO, 2014;THOMAZIELLO, 2007).
Floods occurrence is increasingly common in urbanized areas and create a multitude of hazards and socioenvironmental vulnerabilities in many parts of the world. As demonstrated in the study by Galloway (2008), which presents the impacts of the Great Mississippi River Flood, occurred in 1993 and of the Hurricane Katrina in 2005, both in the United States, in which thousands of people lost their lives and flood damages were estimated at more than $ 120 billion (U.S.).
According to the emergency database (EM-DAT), an international database on disasters, 98 flood and inundation-related emergencies were registered worldwide in 2013. Since many countries do not keep an up-to-date database for these events, the actual numbers must be even higher. Globally, these events caused 8,355 victims, where Asia is the most affected continent (EM-DAT, 2012). Floods and inundations, as 118 floodings registered, which were recorded there between 1900 and 2013 also heavily affected Brazil. These disasters caused 7,668 fatalities and affected more than

SOCIOENVIRONMENTAL RISKS AND VULNERABILITIES CAUSED BY FLOODS
The discussion about social and environmental risks seems to be intensified recently, presumably because of the increasing occurrence of a variety of natural disasters. In addition, potential risks seem to be generated at a steadily increasing pace, due to the highly accelerated process of modernization (BECK, 1992;MATTEN, 2004). These risks have emerged as one of the major causes of the capitalist system and even raise capital in the insurance industry as well as use the production of objects for the prevention of risks (BECK, 1992).
Several scientific research areas focus on risk as the object of their studies and approach the concept from different angles (e.g. environmental, social, economic, political or medical), thus adding high levels of complexity when studying it. The risks may be related to the climate change, human interventions in the environment and subsequent global environmental degradation, as well as to situations involving personal relationships, family and sexuality (GIDDENS, 2000). These situations generally contribute to the induction of stress and tensions within the population.
Regarding environmental changes, different social groups will be affected by different types of risks and as well as different levels of risk exposure. Depending on living conditions, access to basic sanitation and medical services, and the particular socioenvironmental situation such groups will have their lives affected in various levels. The latter will determine the level of vulnerability for any given social group.
The close relationship between risk and vulnerability is an extremely important issue, since the level of vulnerability of a particular element (i.e. an area, a society, a natural resource, etc.) is a determining factor for the social and environmental consequences or impact of a particular risk. An assessment of risks is essential to identify all the factors, which potentially affects a particular element (PEREIRA; SOUZA, 2006). For Freitas and Cunha (2013), hazards such as floods and inundations can affect human beings directly or indirectly, individually or collectively. The level of vulnerability -regarding ecological or social conditions -is related to the response capacity towards the hazard. Adger (2006) on the other hand considers vulnerability as the state of susceptibility to damage from exposure to stress associated with environmental and social changes and a lack of adaptability. Given the characteristics of this research, we decided to use the concept of environmental vulnerability according Oni and Okanlawon (2013), for whom the term social (or environmental) vulnerability means that vulnerability is not only influenced by exposure to causes related to environmental stress, but also by social conditions. Within this context, vulnerability is the ability of a social group or individual to anticipate and recover from the impacts of disasters (WISNER; BLAIKIE; CANNON, 2013) and the increase of floods in urbanized areas is a good example of these impacts.
Several concepts for the terminology of floods or inundations can be found in the scientific literature on the subject. For Tucci (2008), two types of floods can occur in urban areas: 1) floods due to urbanization, i.e. by the use of dirt, which increases impervious areas, and by canal systems. 2) spontaneous floods in riverine areas, which mostly affecting illegal settlements in large riverbeds.
In riverine areas, floods are a natural phenomenon in river dynamics and statistically rivers are likely to overflow every two years in average. However, natural floods may be aggravated due to the obstruction of a river's flow through embankments and bridges, silting and poorly implemented drains (TUCCI, 2008). In this paper, the term "inundation" will be used for natural events, while the term "flood" will be used for events with anthropic causes. Inundations are considered natural phenomena, which periodically occur due to increased levels of precipitation.
Riverine inundations may be amplified because of human actions. Floods, on the other hand, occur when parts of the precipitation in a hydrographic basin are unable to permeate the ground. Such precipitation is then retained by an interceptor element and flows until they reach a watercourse. Consequently, the flow of this watercourse gradually increases until it reaches a limit before decreasing again slowly. Increased discharges of water over a certain period are called "flooding" or "overflow" (OSTROWSKY; ZMIROWICZ, 1991). Onwuemele (2012) complements that floods can be described as the overflow of a large amount of water on an area of land, which is usually not submerged. This can result either from exceeding the local drainage capacity or from a combination of extreme hydrological and meteorological events with influence by anthropic factors. Floods cause a sudden and very intense barrier when it comes to space and time, and display very short periods between precipitation and the subsequent inundation of the river. Due to the rapid rise of water levels and the high speed by which sediments and debris are transported, floods represent an extreme threat to life, property and infrastructure. Vargas, Werneck and Ferreira (2008) point out that the principles of current employed drainage controls aim at draining precipitation as quickly as possible. This concept is based on flow channeling, which is more expensive and causes major secondary flooding when channelings accumulate and have its peak further downstream. As previously mentioned, floods and inundations have been thoroughly studied and discussed in scientific literature. The possible relation between the occurrence of floods and inundations and the increase in rainfall due to natural climate changes caused by the greenhouse effect has significantly raised awareness for these issues (JOTHITYANGKOON et. al. 2013).
Floods in urban areas can occur due to: 1) Heavy rainfall over long periods of time and overflowing waterways caused by the hydrological cycle unbalance in regions upstream urban areas.
2) Excessive portions of land and the subsequent sealing of surfaces.
3) Illegal occupation of permanent sanctuary preservation areas (áreas de preservação permanente -APPs) such as floodplains, known inundation areas and wetlands. 4) Obstruction of pipes through debris and sediment. 5) Inadequate drainage facilities. 6) Urbanization itself when the increased flow is due to plumbing and waterproofing.
Considering urban drainage, sewage can become a major inducing flood and erosion factor, especially in hilly areas with human settlements (VARGAS; WERNECK; FERREIRA, 2008).
In order to obtain a more complete and thorough understanding of flood hazards, it is necessary to integrate human and natural systems, such as the interrelationship between human activities and natural phenomena (CREUTIN et. al., 2013). As previously mentioned floods can be caused by natural factors and be amplified by anthropic factors through the interaction between social and environmental systems (vide supra). For some authors, e.g. Ribeiro (2008), the most vulnerable flooding areas are those most vulnerable in socioeconomic terms, such as the part of the population with low or no income who cannot reside in safer locations.
Nevertheless, not all population segments with low income or irregular occupations inhabit areas vulnerable to floods (FREITAS; CUNHA, 2013). Some affected neighborhoods accommodate predominantly residents from middle and highincome brackets as in Atibaia, which is the target area for this study.

METHODS
The objectives of our study are: Simultaneously, a process of disorganised occupation can be observed. This highly dynamic process has intensified real estate speculations and it is favored by welldeveloped traffic routes (HOEFFEL et. al., 2009;SEIXAS et. al., 2012), as the easy access via the Dom Pedro I and Fernão Dias highways has amplified the impacts towards urbanisation and population growth within the city.  The Atibaia river basin is the home of one of Brazil's main industrial centers.
Apart from also being densely populated and a major agricultural area, it is almost exclusively responsible for the water supply to the cities of Atibaia (90%) and Campinas (95%). As the Atibaia River is also one of the main rivers feeding the Piracicaba river basin, it is responsible for the water supply for almost 4.5 million people in 60 towns in the region. Despite its strategic importance for the region, the Atibaia River is heavily polluted. About 90% of the urban domestic sewage and 20% of the industrial waste generated in the region are disposed untreated into the river (COMITÊS PCJ, 2010). The core area of this study is the part of the hydrographic basin of the Atibaia River, which lies within the boundaries of the Atibaia municipality. A summary of floods that caused damage and a conclusive analysis of its intensity in the period of 2002 is presented below:     as the importance of secondary disasters and the emergency management agency staff's lack of preparation were classified as average. The level of vulnerability for the scenario and the community was considered very important. The evolutionary pattern of the disaster was classified as sudden and unpredictable, with a tendency to increase, resulting in a total level of high disaster intensity (SEDEC, 2011).

Floods
As initial response actions to minimize the impacts of the floods emergency assistance was provided. Later, a series of studies were initiated, which focused on identifying the causes of the floods, and developing measures to avoid them.
Emergency measures included removing silt from the Atibaia River in four times.
However, although these actions probably will be beneficial for human, the risks and vulnerabilities in the short term, isolated local actions, as in this case, are unlikely to solve the problem in the long term. According to Hardoy and Pandiella (2009), governments tend to focus on quick responses to emergencies and recovery, while the implementation of preventive disaster strategies are left for an uncertain future.
Intensifying the problems arising from these disaster events was a conflict regarding the reactivation of PCH Atibaia, which is located in a rural district in the county. Some residents argued that the dam of the PCH was supposedly restricting the natural flow of the river and should be responsible by flooding the urban area of Atibaia. This hypothesis was supported by the report of an engineer, who was hired by a commission of affected residents (AMBAE). Conversely, a preliminary study presented by the DAEE concluded that the PCH should not be hold responsible for the floods. The minimal backwater, resulting from the dam could not account for the events of the observed magnitude (SSRH, 2012). Disasters should be managed by emergency services in accordance with the urgency that the risk demands it. They must be performed in accordance with operating procedures defined earlier, as decisions need to consider and coordinate the various management policy organizations responsible for the disaster area.
The necessity to use environmental planning in order to minimize the impacts caused by unplanned urban expansion becomes even more obvious, as well as the necessary implementation of management programs, which consider actual local characteristics, vulnerability concepts and environmental risk assessments.
Methodological approaches to manage environmental risks include the identification and analysis of risks, the definition and implementation of preventive measures for accidents and risk reduction, planning for contingency situations, public information and training as well as social mobilization for self-defense.

CONCLUSION
Floodings and inundations cause multiple socioenvironmental impacts. They are driven by an intense urbanization process, which often occurs without adequate territorial planning. The occupation of APPs needs to be evaluated considering various aspects, which involve proper planning laws in order to set clear criteria for territorial management. An active surveillance service should be established, so that these occupations are effectively inhibited in the future. Unfortunately, improper approval of parcellations, which are often motivated by other interests and mostly legitimized by the local government, are hard to prevent. These areas, once regulated and approved by the land use and occupation laws, feature an infrastructure, which favors occupation by more privileged social groups. The illegal occupation subsequently leads to low building standards, but even these low-standard buildings hamper future removal. Illegal occupations in areas with elevated risk and vulnerability levels should be closed considering the restrictions imposed by environmental legislation, but often these issues are ignored due to real estate interests, which involve various social factors. The municipality has to monitor these areas, so as not to allow their occupation, and simultaneously provide alternative housing schemes for the communities. The mapping of risk areas and the implementation of appropriate management strategies would allow a significant decrease of disaster risks. Still, most municipalities do not have a program for flood prevention, or a contingency plan to act timely after flooding events, even though these may be recurring problems. Another problem to tackle is that prevention and flood control measures usually correspond to changes, improvements and structural and technical work, which often do not involve the communities affected. Involving communities to create and develop flood prevention and reaction schemes is important in order to ensure efficient and effective protection in the short and long term. The continuity of these processes is also very important, so that the population of these communities be better prepared to confront repeating floods and thus reduce damage. The difficulty in the creation and implementation of programs of flood control and prevention is the fact that these phenomena are not always predictable in Brazil. They are influenced and depend on a variety of intricately correlated factors, as the concentration of precipitation per time and area, level of urbanization, soil permeability, waste volumes on public roads and rivers and others.
Therefore, the formation of interdisciplinary teams, which can discuss and analyze the problems of flooding in a broad and integrated context, as well as the implementation of studies that allow improved understanding, techniques and procedures, is essential for the development of plans, programs and measures to prevent, combat and control flooding.