Urban populations are rising all over the world. According to the United Nations 60% of global populations is projected to live in urban area’s by 2030. The formation of the urban heat island effect (UHI) and it’s impact on human health and well-being by the increase of heat stress in hard surfaced urban area’s has been described and measured by a multitude of studies. (Oke, 1989) The cooling ability of urban green infrastructures (Pauleit et al., 2020) with trees in particular is currently widely acknowledged. (Rahman et al., 2020). However, planting trees in city centres where they are most needed for a healthy and sustainable living environment still remains a challenge due to extreme growth conditions (Sjöman et al., 2018). Densely populated urban area’s are constantly developing and due to the limited above and underground space new planted trees rarely reach maturity. In addition the underground utilities with frequent maintenance, soil compression and the lack of nutrients further complicate healthy and consistent growth of tree canopies. (Ferrini et al., 2019) If we want our trees in the hardscaped everchanging urban environments of city centres to provide many of its benefits for the next generation, the technical design for planting, maintaining and strategically locating trees in urban area’s should be reassessed now.

Many cities in Sub-Saharan Africa struggle to access reliable and adequate quantities of potable water for diverse water requirements. Under pressure of climatic change, urbanization and economic development, freshwater resources are becoming scarcer. These pressures combined with outdated infrastructure, pose a giant challenge to the Greater Maputo Region to meet their water demand in 2050. This report aims at identifying and analyzing pathways, using stakeholder preferences, that support SUWM and bear the potential to close the supply-demand gap in 2050.

This report utilizes population and demand forecasting to determine the gap between future supply and demand. Hereafter, alternative technical, social, and environmental methods to augment the Greater Maputo Region’s water supply are identified through a literature study. Furthermore, two distinct methods are used to develop scenario’s that augment the supply demand gap. The first being a technical analysis using multi-criteria decision analysis and the second a serious game that is to be played with stakeholders. At last, these scenarios are used to develop a framework that is technically feasible and approved by stakeholder opinions in the serious game.

It was found that the population of the Greater Maputo Region will grow from 2,8 million in 2017 to 6,9 people in 2050. Furthermore, under the pressure of economic development, population growth and urbanization, water demand increased from 9 million m3/day in 2017 to 22 million m3/day in 2050. This increase in demand, in the case of a business-as-usual scenario, amounts to a deficit of 1,2 million m3/day in 2050. The sector that consumes most water is agriculture, followed by industries and households. Furthermore, under climate change precipitation decreases over time whereas temperatures increase. Especially during the dry period, more evaporation and less rainwater is expected, highlighting the need for alternative water supply methods to ensure a steady availability of water.

Alternative methods that support SUWM such as dams, stormwater harvesting, rainwater harvesting, wastewater reuse and desalination were found to be most suitable approaches to augment the Greater Maputo Region’s water supply. However, it was also found that these approaches are not very efficient without the right urban context and socio-political and economic measures. Economic and social-political measures should incentivize water savings and fair distribution.

Two distinct methods were used to create scenarios to close the Greater Maputo Region’s supply demand gap. The first, multi-criteria decision analysis showed that that in the case of a high weight attributed to the cost of approaches, rainwater harvesting, stormwater harvesting, and dams are the most suitable options given the selected criteria and their respective rank. Whereas in the case of a low weight of the cost, wastewater reuse, stormwater harvesting, and rainwater harvesting are the most suitable. The second, a serious game that mimics the WASH situation in the Greater Maputo Region which showed that players focus on sustainable, circular, solutions, but that they are hard to implement because of financial limitations.

Ultimately, this report indicates that both decision analysis and serious gaming provide valuable insights for enhancing water supply in an urban context. In this report, both methods indicate that there is a preference for circular (sustainable) approaches. Such an ideal, circular, and sustainable, water system in the Greater Maputo Region, was found to be supported by decentralization of the water sector. In this case, decentralization of the water sector to a neighbourhood scale shapes niches for sustainable water supply approaches and within these niches, the local context of the neighbourhood determines the type of water supply infrastructure that is most suitable. Furthermore, the technical approaches are to be supported by socio-political and economic measures. Altogether, a combination of SUWM supporting approaches supported by political and socio-economic measures can close the supply-demand gap in 2050.

This paper focuses on the regeneration and reuse of remnant wasted structures, lands in Rotterdam into future ecological hotspots to foster biodiversity, improve the quality of people and species’ lives. Due to a phenomena of pressing urbanization undergoing in the city, the majority of the old industrial, harbour areas or structures are demolished and replaced by new ones with different functions and forms so that the memory of the past urban structures gets erased. Some lands instead are used and then abandoned or even never used and left uncultivated. These, usually covered by wild vegetation, can host a high range of biodiversity, especially in not polluted soils. So what is the future of the Wastescapes in the city of Rotterdam? The reuse and regeneration of abandoned spaces in the city can offer great potential for urban biodiversity and also for the improvement of socialization. For example, a wasted space can also be converted into a community garden where people can meet up and explore nature. The sense of belonging to a place is fundamental and it can be discovered again via urban landscape design. Any space can represent a point of integration and be perceived with its own identity. Citizens should be led to understand that a space can represent a place of sensorial and mental experience. At large scale, the transformation of four critical industrial areas along the River Maas into new ecological hotspots leads to the increase of urban vegetation (biodiversity), the depollution of the soil, water and air. At medium scale, a Southern area of intervention is chosen : Waalhaven and surroundings. This represents a crucial crossing point where the contrast between city and harbour/industry is much stronger and more evident . At small scale, the district of Oud Charlois is chosen as an experimental area to intervene and test the success or failure of the intervention. The design framework applied to the project site represents a resilient, efficient, sustainable, circular system that can adequately show the potential of Wastescapes in the city in urban, social and ecological terms. This consists in the selection of particular zones of intervention where various design eco-components are applied according to duration, scale, site issue. This “Toolbox” represents a set of flexible urban elements capable of promoting biodiversity, addressing climate change and easing urban fragmentations. In particular, the quality of people and species’ life is improved by some processes of phytoremediation of polluted soils which, combined with plant gradients, can lead to the improvement and enjoyment of the urban environment (water, soil, air).

The Rotterdam urban fabric is built in an area of amalgamation of very interesting landscape conditions surrounding it. Defined by the rich natural and cultural history, this structure has been home to different habitats for a variety of flora and fauna. However, the urban core disconnects these areas due to the lack of diverse ecological green and blue networks. The urban core of Rotterdam is abundant with characterless and unused spaces that can be termed as urban voids. The paved and stony surfaces, large infrastructure, abandoned structures, etc in these spaces heat up the unbuilt (or are they really ‘unbuilt’) spaces and create hotter environments. This, with the changing climate also poses a risk of disasters like flooding, heat islands, and habitat loss. These Urban voids are not designed for ecology and resilience to the changing climate. This project envisions creating an ecological spatial design framework through landscape architectural principles for the urban fabric of Rotterdam by making use of the urban voids, thereby also making it resilient to climate change. This is achieved by identifying the urban voids on a regional and local scale and intervening at the right degree with the desired toolbox of landscape architectural principles generated through case studies of different typologies. The voids are extended into the surrounding habitat conditions so that the ecological connections become stronger. Theories, mainly the patch-matrix-corridor theory, create the backbone of the framework strategy. Target species based on the relevance and location of intervention are identified and incorporated in design generation. Design elements tackling issues of heat islands and flooding are incorporated in site design based on the existing situation on site. These are combined with the local characteristics of cultural, ecological, and functional layers. This results in creating a landscape design framework for the Rotterdam urban area connecting the ecological biotopes around the region and catalyzing climate change resilience in the region, by making use of the urban voids. The design will look at creating a network through the urban area on a regional scale by studying the overall regional ecological composition. This is important to create a larger network for biodiversity and ecosystem services in the Rotterdam region that is home to different types of habitats, evolved through historical, natural, and cultural processes. This will be followed by detailed spatial design on local scales in the urban voids by taking into account the various characters native to these voids, like the morphological, socio-cultural and ecological values. This will result in the creation of a toolbox of different typologies that could be used to reanimate these voids ecologically as well as for climate resilience. These new spaces will bring identity to these spaces and use them to create new local flows respective to the area of design.