Urban Agglomeration and Supporting Capacity: The Role of Open Spaces within Urban Drainage Systems as a Structuring Condition for Urban Growth

Urbanisation greatly changes the natural environment—city growth may cause urban sprawl, increasing land consumption and infrastructure demands, with consequent built and natural environments degradation. To face this challenge, the supporting capacity of the natural environment needs to be addressed in the urban planning process. This chapter will particularly discuss urban drainage role in the planning context, integrating engineering, urbanism and landscaping in order to set the basic conditions towards a sustainable city development. Urban drainage systems (and the related urban rivers) play a crucial role in city planning, once it intermediates the needs of the built environment, providing safe areas free from flooding, and the demands of the natural environment, giving space and passage to floods. This particular feature gives to the drainage system a spatial structuring characteristic and it provides opportunities to revitalise city areas, improving biodiversity and recovering environmental values. On the other side, a city open spaces system is the main reserve of urban areas for sustainable urban drainage interventions. The adequate land use planning and consequent management of these open spaces shall be in the core discussion to produce integrated and functional solutions for built and natural environments

Sistemas de espaços livres e drenagem urbana: um exemplo de integração entre o manejo sustentável de águas pluviais e o planejamento urbano

In the last decades, the traditional view of urban drainage has been modified by an integrated approach of sustainable urban drainage management and urban planning. Open space systems appear as actors of environmental integration, providing opportunities to create multifunctional projects, combining drainage solutions with the urban growth and the union of fragmented areas. In this work, the object of study is Xavier de Brito Square, located in the Tijuca neighborhood, in the city of Rio de Janeiro. Considering its surroundings and the most affected areas by floods, this work proposes a route along the Maracanã River, to connect Xavier de Brito Square to other adjacent squares, seeking to improve the connection between the urban space and the river, integrating the existing open spaces. In addition, sustainable urban drainage measures were proposed, such as permeable pavements, rain gardens, and detention basins. With the aid of mathematical modeling, it was possible to analyze the effects of the proposed measures facing flood events.Nas últimas décadas, a visão tradicional do projeto de drenagem vem sendo modificada por uma abordagem integrada de manejo sustentável das águas pluviais e planejamento urbano. Os sistemas de espaços livres surgem como atores de integração do ambiente, configurando oportunidades de criação de projetos multifuncionais, por exemplo, acumulando funções para soluções de drenagem, organização do crescimento urbano e união de áreas fragmentadas. O presente trabalho tem como objeto de estudo a praça Xavier de Brito, localizada no bairro Tijuca, na cidade do Rio de Janeiro. Após reconhecimento do seu entorno e análise das áreas mais afetadas por inundações, optou-se por formalizar um percurso ao longo do Rio Maracanã, buscando melhorar a relação entre o espaço urbano e o rio, e estabelecer a integração dos espaços livres, conectando a praça Xavier de Brito às demais praças adjacentes. Além disso, foram propostas medidas de drenagem urbana sustentável ao longo do percurso escolhido, como a utilização de pavimentos permeáveis, jardins de chuva e bacias de detenção, por exemplo. A partir de modelagem matemática, foi analisada a resposta da região às inundações com a aplicação das medidas propostas

Environmental Protection Areas as a Strategy to Increase Flood Protection in Metropolitan Regions: A Case Study in Maricá, Rio de Janeiro, Brazil

In peripheral countries, the lack of adequate urban planning associated with natural dynamics intensifies the existing vulnerabilities of the environment, causing physical and material losses. Therefore, this research aims to discuss the potential use of Environmental Protection Areas as a tool to drive urban growth with a low-impact development, helping to mitigate urban floods and bringing nature into the city landscape. The municipality of Maricá, located in the metropolitan region of Rio de Janeiro, Brazil, is taken as a case study. The method proposed to drive the regional environmental planning and management can be described as a three-stage method coupled with the adapted SWOT Matrix, following: the diagnosis, the prognosis, and the action plan. This process points to the definition of a Hydrological Interest Area that would allow not only the restoration of local vegetation and a better interaction of the population with the watercourses, but also the recovery of areas that have been gradually impacted by the urban expansion. The method presented in this research allows its application in different urban contexts, once it has the objective of recognizing the strengths, weaknesses, opportunities, and threats to allow the elaboration of sustainable actions and guidelines

An Integrated Plan to Sustainably Enable the City of Riohacha (Colombia) to Cope with Increasing Urban Flooding, while Improving Its Environmental Setting

This paper describes the emblematic situation of a Colombian coastal town seriously threatened by flooding and presents the whole process undertaken to elaborate an integrated action plan to cope with this problem, while improving the natural and built environment. Such a plan is a product of a project, winner of a National Colombian call for climate change initiatives, which included a thorough modeling process based on the MODCEL urban flood model, an articulated participatory process including a specific structured inquiry mainly aiming at providing data suited for model calibration, a creative phase to propose candidate alternative solutions and a quite integrated evaluation exercise which supported the transparent choice of the most sustainable plan alternative. The approach and the experience can be valuable for many other cases in Colombia and around the world, particularly in developing or emerging countries where data are scarce. The added value of this paper lies in showing a whole, integrated process, well articulated, where all pieces are indispensable but simple enough to be replicated in many cases. It merges the fundamental participatory component with an equally fundamental technical-scientific component of characterization, modeling and integrated evaluation. The multiple steps of the process are illustrated with sufficient detail to allow the reader to grasp what was actually done and why, providing a practical guide for other cases