Blue-Green Infrastructure (BGI) in Dense Urban Watersheds. The Case of the Medrano Stream Basin (MSB) in Buenos Aires

Abstract

Conventional urban drainage approaches have historically focused on the volume of stormwater to be displaced with the aim of moving it as fast and as far as possible from the city. They have also been negligent regarding water quality and the inherent value of watercourses to distinct forms of life in cities, from maintaining biodiversity to providing recreational space for residents. Contemporary responses to these issues point to a paradigm change: They seek to replicate the natural mechanisms of absorption and retention, with the aim of addressing pluvial drainage needs closer to the site of origin. This article aims to explore the extent to which such an approach could be accommodated in one dense and highly impervious setting in the Global South. Specifically, it compares urban morphology, land value, hydraulic performance, and politico-institutional conditions of grey and Blue-Green Infrastructure (BGI) scenarios in Buenos Aires, Argentina. The findings suggest that even in very dense and impervious urban basins it is possible to implement BGI with a significant effect in achieving urban-sustainability goals. Furthermore, the results demonstrate that it is possible to deculvert watercourses in line with Compact City principles through the development of hybrid BGI/grey-infrastructure systems.

A new landscape architecture : The living fences experience in Buenos Aires

“…Moreover, we found contradictions between the city government's stated intention to increase green coverage, through for example the high-profile programmes that have been launched in the past decade (e.g. Buenos Aires Verde), and the dearth of green (and blue) infrastructure approaches to address socio-environmental challenges and adapt existing city infrastructures (Kozak et al, 2020). At the society level, social and spatial inequalities shape the provision of and access to urban green spaces (Baxendale and Buzai, 2019; Perelman and Marconi, 2016), which results in a particular dearth of green in denselybuilt middle class areas and difficult local access to regional parks located in poorer southern neighbourhoods.…”

Management of Urban Waters with Nature-Based Solutions in Circular Cities—Exemplified through Seven Urban Circularity Challenges

“…Measures to promote permeability are also included in this category [28]. By implementing NBS throughout the city, it is possible to begin re-establishing a more natural water balance, reducing runoff peaks and volumes and promoting infiltration, retention and evapotranspiration [29]. Groundwater recharge is an important factor in securing the drinking water supply of many cities [30].…”

“…NBS has changed the approach of dealing with urban water [41]. The concept of circularity dictates focussing not only on waste valorisation (i.e., through treated wastewater reuse), but also on the treatment process itself, by using eco-designs such as the various NBS systems [29]. NBS as urban green infrastructure provides sustainable solutions to the pressing issue of water management in urban and peri-urban areas.…”

Going Green and Going Dense: A Systematic Review of Compatibilities and Conflicts in Urban Research

“…Finally, a large number of studies included in this review explored methodological frameworks or tools to foster dense and green cities, namely by facilitating the management of trade-offs between urban densification and the provision of green space, such as urban development models and scenarios [124][125][126][127][128][129][130][131][132][133], frameworks for multiscale or multicriteria assessment of green spaces in the context of urban densification [134][135][136][137][138][139][140], frameworks to optimize vertical gardening, green roofs or sky gardens [141][142][143][144][145][146], or new tools for understanding and measuring how urban design affects green space accessibility [147].…”