Green gutter as a Natural Based Solution for mitigation and adaptation strategy in urban environments

In recent decades, one of the most discussed topics revolves around the issue of climate change and how humans can act to address this problem in the urban environment, given the profound impact of this on human daily life. The overarching goal is the reduction of the causes and the sources of climate change, in order to promote the well-being of the environment, doing the best for it. However, this altruistic pursuit often contends with human predispositions toward self-interest, which are its first concern. A loftier pursuit entails not only mitigating the repercussions and proactively adapting to the yet evolving circumstances, but also doing it in the most natural and environmentally friendly way. Within this paradigm, urban environments emerge as ideal fields where to develop this prospect, particularly through the application of Nature Based Solutions. Urban areas represent focal points where the impacts of climate change will be intensively felt, as they are the heart of the problem, being both victims and sources of it. Numerous sources of pollution and their consequential impacts stem from human activity. Cities must enact integrated policies to achieve greater sustainability, resource efficiency, energy conservation, pollutant reduction, and effective water management. The main goal of this study is to evaluate the efficacy of a gutter as a prospective green wall, in managing water rainfall. The aim is to develop and propose a system capable of mitigating the risk of inundation and flooding, since it would be able to handle extreme rainfall events. The key targets assessed include the system's capacity to reduce peak flow, delay the arrival time of peak flow, and retain water. Additionally, the duration required for the system to completely empty and fully recover its operational functionality will be examined to estimate when it would be ready to manage the subsequent rainfall events. The experimental tests were carried out at the DTU, dept of Engineering Technology, Ballerup, Denmark. The experimental apparatus consists in a prospective green gutter filled with Rockflow by Rockwool’s company, a special type of mineral wool designed to be used in water delay systems, capable of dealing with heavy rain phenomena. The green gutter will represent a mitigation and adaptation strategy that, when integrated into an urban catchment, would serve and help as an additional measure to address climate change. Key finding is the ability to manage the shorter rainfall, so the most intense precipitation events. This could be a significant contribution to enhanced resilience against flooding and inundation, supporting sustainable urban development and climate change adaptation efforts. By effectively delaying peak flow and managing runoff, this system can contribute to establishing a comprehensive framework for water management within a larger project. This may involve incorporating multiple gutters within a catchment area, strategically distributed at key points.