Land Planning and urban waters in Maceió/AL 1

Transcription

1 12 th International Conference on Urban Drainage, Porto Alegre/Brazil, September 2011 Land Planning and urban waters in Maceió/AL 1 Nadja Barros Fernandes¹*; Regina Dulce Barbosa Lins² and Vladimir Caramori B. Souza³ ¹ Faculdade de Arquitetura e Urbanismo, Federal University of Alagoas, Campus A.C. Simões, Av. Lourival Melo Mota s/n, Cidade Universitária. CEP: , Maceió, AL, Brazil. ² Center of Technology, Federal University of Alagoas, Campus A.C. Simões, Av. Lourival Melo Mota s/n, Cidade Universitária. CEP: , Maceió, AL, Brazil. *Corresponding author, nadjabarros@gmail.com ABSTRACT This article focuses on the relationship between land planning and the management of urban waters in the city of Maceió, capital of the State of Alagoas, in the North-east of Brazil. The geographical area studied is the catchment area of the creek Reginaldo, which lies completely within the urban area of Maceió. The area is studied with a focus on the way in which the instruments of regulation of the use and occupation of the urban land have taken into account the management of rain water. The article starts from the premise that an urban river catchment area is an important territorial unit for environmental analysis in the process of urban planning, but acknowledges that this concept has not yet been effectively incorporated into planning actions, and that understanding the interaction between its components allows us to characterise the pressures of the urban environment on the hydrological cycle. The period studied is between 2005 and 2009, these being the years of adoption of Maceió master plan (Plano Diretor) and its complementary laws. The studies demonstrate that in Maceió the conception of urban drainage, or its absence, is dominated by the hygienist focus, and that four years after passing the Master Plan for Urban Development, the plan has not been capable of imposing changes on the conditions of the use and occupation of land, with a view to minimising the impacts of urbanisation on the urban drainage system of Maceió. KEYWORDS Land use planning; urban drainage; urban waters INTRODUCTION The manners of appropriation, organisation and management of urban space are capable of provoking alterations in water bodies, and in their dynamics. Among the negative effects of these alterations to the urban environment are: the degradation of the quality and the reduction in the quantity of water, the reduction in the rate of recharge of the aquifer, the increase in surface run-off, and the consequent floods. With each passing day flooding events have become more frequent in Brazilian cities. In the majority of cases these are a consequence of the very process of urbanisation, and of the continuing hygienist approach of the drainage systems, with an almost exclusive emphasis on the hydraulic efficiency of the drainage networks, and of the serious interference cause by solid wastes. 1 We thank Chris Scott for his translation of this paper. Fernandes et al. 1

2 The situation becomes more critical because of the prevailing social exclusion, which pushes the homes of the poorer populations into environmentally fragile areas, such as valley bottoms and steep slopes (Figure 1), which, as they are not provided, among other things, with the infrastructure for basic sanitation, generate greater pressure on the natural environmental conditions. These processes in turn have indelible impacts on the built environment. Figure 1. Occupation of hillsides and areas liable to flooding in the Reginaldo creek catchment. Source: Fernandes, A situation of socio-spatial inequalities, reflected principally in the segregation of low income populations, has been the result of Brazilian processes of urbanisation and development: product and producer of forms of appropriation and organisation of space strongly characteristic of a form of urbanization full of risks. In the interpretation of Rolnik (2008), the irregular settlements multiply in fragile terrain or in areas in which urbanisation is not [formally] possible, such as steep slopes and areas liable to flooding, [ ] eternally without the infrastructure, equipments, and services which characterise urbanity. In this context, the alterations in the physical urban environment have resulted in the degradation of the quality of the soil, air, vegetation, and especially, water. In Brazil, according to Maricato (2001), the lack of control over the use and occupation of the land has resulted in a predatory and irrational form of occupation which has resulted in problems which are unacceptable at the start of this century: floods, landslides, water pollution, epidemics, etc.. The increase in impermeable areas and the occupation of Permanent Preservation Areas [Áreas de Preservação Permanente (APPs)], in general areas inadequate for human occupations, are most frequently, in the case of Brazil, the result as much of the inability of the population to buy adequate land/housing in the formal market, as of a mistaken housing policy which has not given priority to the reservation of sufficient public land suitable for such housing. Castro (2007) calls attention to the fact that the growth of urban areas has provoked a series of changes in the environment which are reflected in the hydrological cycle to the extent that they alter the state of urban waters in various ways: regime, quality and quantity. These changes, in turn, have an impact directly on the system of urban drainage. 2 Land Planning and urban waters in Maceió/AL

3 12 th International Conference on Urban Drainage, Porto Alegre/Brazil, September 2011 In the urban context one of the principal pressures on the drainage of rain water comes from the way in the subdivision and occupation of the land has been carried out. The practice of the indiscriminate subdivision of the land is one of the principal sources of environmental problems of Brazilian cities, including Maceió. In this way urbanisation exercises pressure on the urban waters which results in the alteration of the state of these waters. On the other hand the management of urban waters, especially the drainage and handling of urban rain water, is intimately linked to the integrated handling of three of the four elements of basic sanitation: the drainage of sewerage, urban cleanliness, and the handling of solid wastes. The understanding of the overlap of waters in the urban environment with other systems which exist in the city is of overwhelming importance for their handling, to the extent that in considering this interrelationship it is possible to minimise the negative impacts on the natural and constructed environments including their populations. Consequently this article has the aim of investigating how the instruments of urban regulation have considered the handling of rain water in the city of Maceió, with emphasis on the relationship between the use and occupation of urban land and urban drainage. To reach this proposed goal both the Master Plan for Urban Development, approved in 2005, and the Maceió Urbanism and Building Code, introduced in 2007, were analysed. These are instruments of urban policy capable of guiding important changes in the management of water in the urban environment. Given the facilities which these instruments of urban control provide one can identify the real perspectives, if the instruments were effectively implemented, of obtaining a reduction in the environmental and social aggravations caused by inadequate practices of handling the elements which affect the quality of rain water and, consequently, urban drainage. The municipality of Maceió, the empirical reference for this study, has an area of km², of which km² are in the urban area, with this being around 45% of the total area. The census carried out by the Brazilian Institute for Geography and Statistics [Instituto Brasileiro de Geografia e Estatística (IBGE)], in 2010, identified a population of 932,608 inhabitants in Maceió, with 931,984 of those people (99.93%) living in the urban area. Finally, it is emphasised that since it was founded Maceió has maintained a close relationship with its waters: the natural port of Jaraguá and the existence of rivers, of the Mundaú Lagoon, and of natural canals and water channels, have been decisive factors for the founding and growth of the city. Of this set of water resources, we he highlight the creek Reginaldo, above all because it is the principal water course of the catchment being studied, and for being completely included within the urban area. METHODS We adopt the concept of urban drainage defined by Porto et al. (2001), the collection of measures which have the object of minimising the risks to which the populations are exposed, reduce the losses caused by floods and enable an harmonic, articulated and sustainable form of urban development. Primary and secondary data were used as sources for the research. In the exploration of primary sources the research involved examining official documents, photographic records, maps from the Master Plan for Urban Development (MACEIÓ, 2005) and the Urbanism and Building Code (MACEIÓ, 2007), the digital mapping of the urban area of Maceió, satellite images and by making visits to the field. Fernandes et al. 3

4 In the exploration of secondary sources we opted for the reading of texts which considered the overlap of urban planning with the four components of basic sanitation. We sought out authors who undertook analyses of the socio-environmental and territorial context with a focus on planning and water management in urbanised areas. We evaluated how the Master Plan of Maceió, the principal instrument of the municipal urban and environmental development policy and the Urbanism and Building Code, which complements that Master Plan, define their directives bearing in mind the actual situation and the implications of the forms of use and occupation of land given the drainage conditions in the basin under study. Three facts were determinant in defining the Reginaldo creek catchment as the geographic reference for the study undertaken. The first is that it is a totally urban basin, as presented in Figure 2, with a drainage area of 26.5 km², in which live around 10% of the population of the municipality of Maceió, and which has a socio-environmental importance in the context of the city. The second refers to the heterogeneity of the standards of use and occupation of land in the area covered by the basin, with settlements of populations of low, medium, and high incomes. The third fact refers to the identification of some of its areas as being areas of risk (MACEIÓ, 2007a) because they contain high densities of population in inadequate places, such as: areas in valley bottoms and on slopes, which are subject, therefore, to the consequences of precipitation and landslides and which interfere directly in the dynamic of the urban waters. Figure 2. Delimitation of the Reginaldo creek catchment in the urban area of Maceió. Source: Base Map of Maceió (MACEIÓ, 2000), adapted by Chris Scott (cwscott.br@gmail.com) RESULTS AND DISCUSSION The first decades of the 19 th century witnessed the beginnings of the development of Maceió, whose urban interventions in water environments were marked by the influence of hygienist thinking, and which resulted in alterations to the original environment of the city, above all through systematic actions of land reclamation and drainage (CAVALCANTI, 2002). That 4 Land Planning and urban waters in Maceió/AL

5 12 th International Conference on Urban Drainage, Porto Alegre/Brazil, September 2011 influence is still present in innumerable attitudes of the State and of the maceioense population in their daily life, such as: the filling of areas liable to flooding, the modification of the natural drainage canals with the straightening and lining of the natural bed, the disposal of sewerage and rubbish in the water courses with the belief that the movement of the waters would take responsibility for carrying it to the mouth (IDEM). The standard of urbanisation observed in Maceió and the way in which the use and occupation of the land has occurred have been the principal elements of pressure on the physical environment, and especially on the water courses and urban drainage. According to Lins et al. (2004), the city [Maceió] grew in a [territorially exclusive] and environmentally predatory way, guided by powerful specific interests and, an almost total, lack of public interest in its processes of planning and management. Maceió grew and the drainage interventions were always directed toward an increase in hydraulic efficiency, with the connection of the micro-drainage network to the natural drainage canals, as described by Accioly and Souza: With respect to superficial drainage, the result is an intense process of impermeabilisation of the soil, without control, with systems of drainage based on an increase in the hydraulic efficiency of the networks and with a high level of degradation of the urban water bodies. The consequences are observed in frequent and progressively more critical floods in the urban area (ACCIOLY and SOUZA, 2007). This situation is seen in the Reginaldo creek catchment which is one of the principal environmental systems of Maceió. The city has fifty neighborhoods and seventeen of them are totally or partially within the Reginaldo basin and its growing urbanisation has increased the soil imperviousness. In the valley of the creek Reginaldo, problems of floods, collapsing dwellings, landslides, erosion, water pollution and endemic health problems, have been registered. The low income population localised in the basin lives on steep slopes and valley bottoms, almost always without the provision of infrastructure and public services. This situation compromises the conditions of urban waters. In the context of urban drainage it can be seen that territorial planning does not consider the drainage basin as an element of reference, in spite of this being a basic principle established in the laws of Water Resources (Law No /1997) and of Sanitation (Law No /2007). It can also be seen that there has been an attempt to minimise the pressures and impacts of urbanisation on the hydrological processes, by means of the establishment, in the Master Plan for Urban Development, of minimum levels of permeability for plots. However, the result of this attempt has been absolutely inefficient because of the standards of occupation of urban land proposed: the limits for impermeabilisation are valid only for plots larger than 1200 m 2, which represent an insignificant percentage of those in the basin. One asks oneself: whether what was planned was fruit of a misunderstanding of the problem to be resolved, or whether the solution was linked to other interests, of a land ownership and/or real estate nature, which were in fact uninterested in its efficiency. The level of permeability foreseen in the Urbanism and Building Code does not represent an instrument which promotes the reduction in the surface run-off and the consequent infiltration of rain water. On the contrary, it induces an increase in the impermeabilisation of the soil, the result of which will be, among others, an increase in the surface run-off currently observed and the aggravation of the socio-environmental damage. In other words, this urban parameter is meaningless for the reality of the Reginaldo creek catchment and for other urban areas, given that it determines that plots with an area of less than 1200 m 2 are exempt from any control of permeability. Furthermore, the pattern of subdivision of land, above all in the basin studied, corresponds to the existence of plots the great majority of which have an area of less Fernandes et al. 5

6 than 1200 m 2. We reinforce, therefore, that in this case the Master Plan has not succeeded in meeting the precepts of sustainability presented in its initial objectives and directives. The Master Plan of Maceió brings with it a preoccupation with the compatibilisation of urban growth with the natural environment and the search for sustainable development, however, it does not define the strategies and the actions which should be prioritised in order to reach the objectives proposed. Today, more than four years after its approval this environmental preoccupation has not moved past the level of rhetoric, as, in general, the actions implemented have not respected the conditions of the natural environment, being as they are the result of planning (which although it observes reality, still does not understand some of the complex relationships between man and nature) which, effectively, has a small or no impact on the sustainability of the systems of drainage. Although the Master Plan of Maceió presents an ample environmental discourse, in practice, it is not capable of proposing alternatives which promote the reduction of the impermeabilisation of the soil, whether in public or private buildings, or respect for areas of permanent preservation, such as steep slopes and valley bottoms, aspects which impact directly, and negatively, on the quality and quantity of urban waters. In synthesis, the urban reality of Maceió demonstrates that the presence of urban waters was ignored during its process of growth, and that the need for recognition of the increased importance of the functions of water in the definition of the directives for the use and occupation of land was barely considered. From the perspectives of urban planning and management one cannot identify efforts for the integrated resolution of the problems related to water in the urban environment, and for giving greater value to the hydrological cycle with a view to encouraging an urban (re)design which effectively incorporates some well established elementary principles as the focus for the sustainability of drainage systems: the use of the drainage basin as a reference; the minimisation of and compensation for the impacts of urbanisation on natural processes; the non-transference of impacts; the preservation of natural water courses; among others. CONCLUSIONS In the local case, the investigation opened by the theme is still situated in a new field of academic discussion and public policies, and is, therefore, of great importance in the research on aspects of contemporary urban reality, in its distinct dimensions and scales, and can point to new paradigms for the future of the inhabited space - territory and environment, and of public policies related to the management of space. The results obtained demonstrate that the restrictions on occupation foreseen in the Master Plan and in the Urbanism and Building Code have not had the capacity to modify the patterns of the use and occupation of the soil of the Reginaldo creek catchment to the extent that they were able to alter the degree of permeability of the plots. In other words, the directives of the Master Plan, especially those which refer to the degree of permeability, have not encouraged changes in a paradigm of urban growth rooted in the expansion of impermeabilised areas, with serious consequences for the increase in the frequency and magnitude of problems related to rain water. The environmental quality of the urban drainage basins of Maceió demonstrates that proposals which could minimise the impacts resulting from urbanisation are not implemented, given that they still only appear in very timid, and sometimes mistaken, forms in their most important instrument of territorial and environmental management, the Master Plan for Urban Development, and its complementary instrument, the Urbanism and Building Code. 6 Land Planning and urban waters in Maceió/AL

7 12 th International Conference on Urban Drainage, Porto Alegre/Brazil, September 2011 Furthermore public works have not incorporated the new paradigm for urban drainage. The public powers continue to approve and execute interventions (works) in areas of risk protected by the Forest Code, Law 6766, Law /2007, Law 9.433/1997, etc., in opposition to the idea of sustainability. An example of this is the project which is, today, being carried out in the same Valley of the creek Reginaldo, with a major road axis, housing programs, etc. The current Master Plan presents advances in relation to the previous norms. It points out important questions related to ways of overcoming the problems of urban drainage and environmental sanitation and incorporates the principles of the Statute of the City. However, the question is still treated in a generic way in the Master Plan while it is interpreted in an equivocal way in the Urbanisation and Building Code. Now, more than five years since its approval that Plan presents itself more as a protocol of intentions than as a norm with strategic elements which indicate more effective action. The directives of the Master Plan did not materialise in the Urbanisation and Building Code and the theme of urban drainage did not receive due attention during the formulation of proposals (LINS, 2011). The conclusions constructed from the empirical analysis of the Reginaldo creek catchment, highlight that: (i) the form in which the occupation of the land has taken place, and the absence of adequate levels of sanitation services, especially sewerage and the handling of solid wastes, have been the principal pressures leading to the degradation of that basin; (ii) in spite of these pressures, the institutional responses still do not recognise the relationship between urban planning and water management at this territorial scale; and last, but not least important (iii) although there exists an understanding of the relationship between the growth of cities and the questions linked to basic sanitation, the public policies in the field of urban drainage are not defined on the basis of a recognition of these relationships nor, even, of the distinctions between different scales of planning and management. The analysis of the territorial management of urban space, originating in a process of both planning and social practices, and in its interrelationship with urban waters privileges an integrated focus on space and urban services, and above all on the infrastructure of basic sanitation. However, the results of the research point to the need for urban planning to move closer to matters related to basic sanitation, given that this is still treated principally in the engineering and public health fields, as a way of modifying the traditional processes of urban and environmental management in Brazilian cities, which are frequently weighed down with equivocal beliefs. Finally, the discussion of the theme, and its associated problems, is more familiar in the domains of the engineering disciplines than in the field of architecture and urbanism where the understanding and analysis of the subject is still limited. The necessarily interdisciplinary approach, incorporating aspects from the technical to the political, which, even if in a preliminary way, emerges from the investigation undertaken here, simultaneously, on the one hand, enriches reflections on the relationship between territorial planning and urban waters in Brazilian cities, while on the other hand, it points to the complexities involved in overcoming disciplinary based approaches. In the field of architecture and urbanism the incorporation of environmental questions is still in its infancy, though with emphasis on the perception of the hydrological cycle. REFERENCES ACCIOLY, Marcus Patrick B.; SOUZA, Vladimir Caramori B. de. Avaliação do impacto da aplicação de diretrizes do Plano Diretor de Maceió sobre a geração do escoamento superficial. Estudo de caso: Fernandes et al. 7

8 Residencial San Nicolas, Maceió/AL. VI Encontro Nacional de Águas Urbanas, São Paulo, USP- São Carlos, jun CASTRO, Leonardo M. Alvim de. Proposição de metodologia para a avaliação dos efeitos da urbanização nos corpos de água f. Tese (Doutorado em Saneamento, Meio Ambiente e Recursos Hídricos) Escola de Engenharia da UFMG, Minas Gerais, Belo Horizonte, CAVALCANTI, V. R. O imaginário local e o ideário higienista: os (des)caminhos da construção da paisagem maceioense. Anais do VI Encontro Nacional de Ensino de Paisagismo em Escolas de Arquitetura e Urbanismo. Construção da Paisagem Brasileira. Recife: CNPq, CAPES, Laboratório da Paisagem UFPE, v. único, Recife, FERNANDES, Nadja B. Planejamento territorial e águas urbanas em Maceió: O Plano Diretor e a bacia hidrográfica urbana do riacho Reginaldo. Dissertação apresentada ao Mestrado em Arquitetura e Urbanismo: Dinâmicas do Espaço Habitado. Universidade Federal de Alagoas. Faculdade de Arquitetura e Urbanismo. Maceió, f. LINS, Regina D. B.; CAVALCANTI, Verônica R.; SANTANA, Lucicleide; ZACARIAS, Paula; PENEDO, Rafaela C.; SOUZA, Natália J. Plano Diretor como instrumento da política de expansão e desenvolvimento urbano-ambiental sustentáveis: o (re) conhecimento dos vazios urbanos em Maceió. In: III Congresso Nacional de Meio Ambiente, 2004, Salvador. LINS, Regina D. B. Relatório Estadual de Avaliação dos Planos Diretores Participativos de Alagoas. In: SANTOS JUNIOR, Orlando Alves e MONTANDON, Daniel. (orgs.) Os planos diretores municipais pós-estatuto da cidade: balanço crítico e perspectivas. Rio de Janeiro: Letra Capital: Observatório das Cidades: IPPUR/URFJ, MACEIÓ. PREFEITURA MUNICIPAL. Base cartográfica de Maceió Plano Diretor do Município de Maceió. Lei nº de 30 de dezembro de Código de Urbanismo e Edificações do Município de Maceió. Lei Municipal nº 5.593, de 08 de fevereiro de Coordenação Municipal de Defesa Civil (COMDEC). Plano Municipal de Redução de Riscos. 2007a. MARICATO, Ermínia. Brasil, cidades: alternativas para a crise urbana. Petrópolis, RJ: Vozes p. ISBN PORTO, R.; ZAHED, Kammel: TUCCI, Carlos E.M; BIDONE, Francisco. Drenagem Urbana. In: TUCCI, C. (org). Hidrologia: Ciência e Aplicação. 2ª ed. 2ª reimpressão. Porto Alegre: Editora Universidade UFRGS: ABRH,2001. [p ]. 1ª edição ROLNIK, Raquel. Acesso ao solo urbano: limites e possibilidades. In: BRASIL. Ministério das Cidades; UFSC. Acesso à terra urbanizada: implementação de planos diretores e regularização fundiária plena. Florianópolis: UFSC; Brasília: Ministério das Cidades, p. (p ). 8 Land Planning and urban waters in Maceió/AL