Cristina Santos

By Cristina Santos and Cristina M. Monteiro

This chapter intends to make an extensive review of the influence that Green Roofs (GR) have on the quality and quantity of stormwater. These aspects are very important to define the benefits and the disadvantages of this nature-based solution that is being implemented worldwide to improve the sustainability of urban areas. Previous studies show that the characteristics of GR (such as dimensions, the composition of the different layers and the type of plants) have a major influence on the quality and quantity of the GR runoff. Despite the proven benefits in urban stormwater management, in some reported cases, the quality resulted worst and for some GR conditions, the effect on rainwater retention was minimal. They are key elements to make resilient cities so a clear understanding of their functioning and development is fundamental to avoid and minimize potential impacts of malfunctioning of these nature-based structures.

Part of the book: Urban Green Spaces

By Cristina M. Monteiro, Cristina Santos, Jaran R. Wood and Kim Rosenbom

In recent decades, the increase of building systems and the consequent impermeabilization of the inner-city environment, poses several negative environmental risks, especially those regarding global warming and water management. Urban green infrastructure (GI) provides benefits to urban inhabitants, but their potential depends on their suitable implementation, under the responsibility of different stakeholders. Nature-based solutions (NbS) are an effective means to restore vegetation urban areas contributing to its sustainability and resilience. The use of NbS infrastructure helps to reduce flood incidences, furthermore contributing to the mitigation of the urban heat island effect and air pollution reduction. Several NbS such as green roofs and green walls, rain gardens, infiltration trenches and permeable pavements, are being implemented worldwide as an effective strategy to improve the environmental performance of densely populated urban cities. Lightweight Expanded Clay Aggregate (LECA®) has been widely incorporated in several innovative urban GI solutions due to their key characteristics (e.g. lightweight, porosity and good drainage), developing a crucial role in stormwater management and water runoff quality. This chapter aims to report the potential influence that several NbS have on urban stormwater management, considering several case studies using Leca® LWA—demonstrating their engineering benefits and innovative properties.

Part of the book: Urban Green Spaces