Urban planners can address sustainability by leveraging urban potential for people and nature but face significant challenges in integrating diverse knowledge and facilitating collaboration. Geodesign, as a methodological approach, has the potential to support collaborative urban planning by managing the ‘boundaries’ between diverse knowledge holders. However, there is a paucity of empirical evidence and systematic assessment of its contribution to ‘boundary work’. The latter refers to the efforts to navigate the interface between diverse stakeholders engaged in co-producing knowledge for sustainability. This paper aims to evaluate how a geodesign process facilitates knowledge co-production through boundary work and to assess the scientific credibility, political saliency, and procedural legitimacy of its outputs in sustainable urban planning. We adapt and further develop recent conceptual frameworks of geodesign from a boundary work perspective and propose a systematic, adaptable, and replicable framework and protocol for assessing boundary work in future applications. We tested our approach in a case study of a collaborative geodesign process for ambitious urban transformations with nature-based solutions in the Skarpnäck district of Stockholm, Sweden, involving fourteen planning stakeholders in a two-day workshop. The findings indicate that all geodesign steps facilitated enhanced communication by promoting discussions and collective reasoning, although to varying degrees. Participants acknowledged contributions to knowledge co-production and decision-making by mediating between different perspectives and opinions. Data quality was identified as a critical factor affecting perceived credibility. Reservations were expressed regarding the translation function. Recommendations for future applications include co-designing the geodesign process, improving capacity and skills, and facilitating more integrated planning.

Advancing towards urban futures in which both human communities and ecosystems can thrive requires transformative change (TC). Spatial planning can serve as a backbone for inspiring and fostering the desired transformation of cities. However, to support this transformation, the challenge for spatial planning is to create unconventional plans that account for the complex trade-offs and interactions of different scenarios through participatory procedures. A promising approach for addressing this challenge is geodesign, since it couples spatial co-design with impact simulations. This paper aims to explore how, and with what effects, a geodesign process can support the co-creation of transformative urban plans that enhance biodiversity and ecosystem services while meeting urban development goals. A geodesign process was developed and deployed for a case study neighbourhood in Stockholm, Sweden. Two scenario storylines were developed: one that follows the current city plan, and another one where the most transformative elements of the plan are further emphasized. Fourteen planning stakeholders divided into three groups translated the storylines into actual land use changes and explored the impacts of the two scenarios. The study findings indicate that the geodesign process enabled participants to develop transformative plans that address housing needs while also promoting biodiversity and ecosystem services through nature-based solutions. Participants showed high perceived desirability of TC scenarios in Skarpnäck but were mostly sceptical regarding the plausibility and probability of future implementation. Changes in perceived plausibility, desirability and probability comparing before and after the geodesign process were minor, with some inter-group variation. We recommend practical applications of geodesign to strategically involve key stakeholders throughout study conceptualization, scenario development, and model generation for better consideration of context. Enhancing geodesign tools for userfriendliness is also crucial. We suggest geodesign research to focus more on understanding its impacts on participants as well as scaling up for addressing complex challenges in metropolitan and landscape planning.

Water and land, cities on the waterfront. Throughout centuries human settlements along the water have searched for a well-balanced relation and have produced some of the most beloved european cities, wonderful and prosperous port cities, that are now at risk. They are facing threats brought by the increasing strength of natural phenomena and disasters. To overcome these challenges what needs to be done? The most relevant questions address how, when and what are the priorities. Settled along the waterfront of rivers, seas or oceans, each waterfront city holds specific challenges and requires adaptative measures. While new risks emerge, simultaneously new opportunities to re-imagine these cities and their urban waterscapes come forward.

In the early 21st century, communities inherited waterfronts mainly shaped during the 20th century, which were built on land- fill, using concrete and creating hard surfaces. New opportunities flourish when these areas envision the transition from such rigid, controlling infrastructures to solutions based on adaptation and integration of natural systems. A critical analysis of human actions on the natural environment has the potential to produce alterna- tives that integrate new strategies with ecological functions, favouring smooth systems and a more comprehensive and integrated approach to nature.

The shrinking of biodiversity, unprecedented climate swings and the raising costs of maintenance are symptoms of a planet struggling with climate change. To re-establish a healthy condition, cities seek to develop strategies of adaptation to make the built environment more resilient to face floods, droughts, high tides, tropical hurricanes and urban heat island effects.

To deal with this topic, an ambitious collaborative research network, funded by the Research European Agency Horizon2020 — RISE Marie Skłodowska-Curie Actions, was created to imagine Sustainable Open Solutions on Waterfront Cities facing Climate Change (SOS Climate Waterfront). The initiative acts asa unifying force, drawing together universities and stakeholders spanning Portugal, Poland, Greece, Sweden, Italy, the Netherlands, and Turkey. At its core, the research project summonses the exper- tise of researchers, PhD students and postdoc researchers to uplift scientific excellence through a global partnership.Its primary focus lies at the intersection of waterfronts facing climate change in five key european cities: Lisbon, Gdansk, Rome, Stockholm and Thessaloniki, located in the Atlantic Ocean, the Baltic, the Mediterranean and the Aegean Sea. This multidisciplinary project put together a series of workshops, field work and conferences that served for sparkly ideas and enlightened thinking among the international team, municipal representatives, and a diverse array of experts. Participants covered various fields such as architecture, urban planning, environmental engineering, meteorology, law, economics, landscape, and others. These collaborative workshops involved immersive site visits, in-depth discussions, and targeted efforts on specific sites.

Collectively, the insights produced by this collaborative network offer a wide spectrum of possibilities, earnestly addressing the multifaceted challenges encountered by urban waterfronts in this era of extreme climate challenges. Participants hailing from diverse fields contributed to a cohesive body of knowledge geared towards birthing creative solutions, effectively spotlighting the material and immaterial exponentially rising costs associated with adapting to and mitigating the damages.

The emergent concept of ‘urban porosity’ stands as a pivotal framework, capable of fostering flood absorption, temperature stabilization, and the curbing of energy consumption. To face these present challenges, resilient urban environments include the inte- gration of circular economy principles and the activation of civil so- ciety towards sustainable practices and safeguarding biodiversity, implied through the concept of ‘porosity’. The flow of information between disciplines depends on the interdisciplinary exchange, enhancing the metaphorical meaning of this new concept.

The selection of five European Waterfront Cities aimed to cover a wide range of situations. Lisbon, Rome, Stockholm, Gdansk, and Thessaloniki were the main laboratories. The re- search on Lisbon’s Great Metropolitan Area addressed pivotal queries surrounding sea level rise, coastal dynamics, and human interactions within waterfront regions. Rome and the river Tiber dealt with coastal systems, historical approaches and dynamics in progress covering current transformations along the seaside and the riverfront. Stockholm, recognized as Europe’s fastest-growing city, grapples with pressing climate change challenges at its wa- terfront. Proposals across three urban sites were explored, each holding profound implications for the city’s waterfront landscape. Gdansk provided insights on how to integrate water management considerations into urban design and planning, since the growing amount of impermeable surfaces results in flooding and pollution of surface waters. The lowering level of the groundwater table im- pairs the growth of vegetation and saline intrusion into the coastal aquifers. Thessaloniki adopted a comparable approach, emphasizing the criticality of resilience for specific waterfront sites. Here, global and local expertise converged to envision transformative urban design solutions tailored to natural yet-to-be-rehabilitated waterfronts, with a keen emphasis on adaptive strategies amid urgent climate challenges.

In this publication, to address the complexity of this emergent topic, the editorial board selected original high-quality papers presenting current research, accommodating a broad spectrumof approaches ranging from speculative, informal investigationsto conventional scientific research, included in the organizationof the three chapters of this book. The first regards “sustainable strategies and cultural heritage” as local geographic and historical resources that stand as potent tools geared toward confronting the current and forthcoming societal and environmental conditions. The second chapter, on “urban waterscapes”, covers an imperative need to consider interdisciplinarity and consequent emerging chal- lenges. The third and final chapter on ‘porosity’ explores case-studies and the opportunity to fortify cities with greater resilience amid the dynamic new necessities for a “sponge-built environment”.

“Sustainable Strategy and Cultural Heritage” explores concepts and projects relating water to landscapes and cultural heritage, focusing on the impacts of the contemporary uses. History without geography is meaningless. Each cultural landscape and the way each community relates to its particularities sustains the re-signification of elements of value, new functions or conservation of heritage buildings and sites.

This first chapter gathers articles that privilege the discussion of anthropic transformation, including how tourism and economic factors impact and influence the public space.

Generations that preceded ours have tested and built many solutions which proved to be resilient and some are still active. There are records of artefacts and strategies that were well adapt- ed and yet built with simple low-tech resources.

From the cultural heritage perspective, it is meaningful to ana- lyse projects that were tested over long periods of time, including adaptive heritage, cases that enhance the integration between landscape and heritage. At present, high levels of sustainable efficiency can be reached by using either high-tech or low-tech solutions, mainly learning from the past. In the second chapter, dedicated to “Urban Waterscapes”, the critical discussion within the interdisciplinary group is driven by a search for hidden, sometimes forgotten knowledge to shed light on local, resilient and low-tech solutions. New solutions emerge from the exchange of expertise between various fields of knowledge, such as geographic, social, environmental, etc. Sustainable transformation is often based on transdisciplinary approachesand emerging strategies must include the role of the communi- ties located along the water. Cross visions between cities lead to the exchange of best practices and are used to imagine beyondthe vulnerable physical reality. Risks of floods, high tides, obsolete infrastructures are part of cultural sites along the waterfront. Currently blue and green strategies search for low carbon energy, transition to soft edges and resilient design, mitigating urban heat islands effect. Increasingly relevant are some of the recent research projects that propose innovative resilience methodologies. At pres- ent they are delivered from interdisciplinary teams, also address- ing comparative cases that succeed to preserve and enhance the natural setting and the built environment.

In the third and last chapter, “Porosity”, articles present systems of resilience to adapt and mitigate effects of climate change, such as environmental planning addressing new patterns brought by extreme swings in the waterfront. The concept has been used across-disci- plines, blending architecture, biology, organic forms and processes providing productive conceptual frameworks. It highlights the tran- sition of the built environment from hard edges to soft edges, and focuses on emergent trends of new urban waterscapes that negoti- ate with nature. It includes future strategies able to act like sponges that are able to absorb without degrading. In fact, nurturing a sponge effect portrays the transition from the 20th to the 21st century.

The concept of urban "sponge effect" implies porosity, urban waterscapes, sustainable strategy and cultural heritage. It requires a profound shift in the way of thinking, from the prominent position of control over nature to a dialogue with nature that can be reinter- preted, producing new meaning and applications within a new con- text. This shift has profound implications in the way cities have been designed, in terms of dealing with green infrastructure, integrating nature, organizing regionalization, transportation, sustainable urban development and circular economy. Sponges take and give, are passive and active, thus opening a new realm of opportunities.

Authors were selected through a double-blind peer review process. Each article reveals a concerted collaboration between academic institutions, local planning authorities and cultural institutions fostering a transformative shift in urban thought. Continually pushing the envelope, this ongoing project serves as a catalyst for innovative approaches, aimed at effectively grappling with and adapting to the multifaceted impacts of climate change within urban landscapes. The theoretical discussion includes the selection of a series of innovative urban strategies to be implemented. How will solutions to adapt and mitigate enhance the resilience of cities?

This comprehensive initiative seamlessly integrates cutting-edge technology, meticulous data collection, and imaginative design, culminating in the development of resilient solutions with potential applicability at both local and european sites. Each of the selected cities has water as its backbone, having developed and adapted along the waterline, adding value to its community.

The far-reaching outcomes of this concerted effort have been disseminated through diverse channels, encompassing open-access databases, scholarly publications, and engaging exhibitions. Between chapters, the illustrations consist of design projects that were developed by the collaborative network of experts participating in the research project throughout four years. The five projects on display were conceived as responses to climate change in the five selected cities. Together, they illustrate solutions designed to deal with each city’s specific challenges, offering opportunities to strengthen their resilience, adapting to new climate patterns and minimizing the impacts of the climate crisis on the waterfront.

The projects conceived for the metropolitan areas of Lisbon, Gdansk, Rome, Stockholm, and Thessaloniki demonstrate both sensitivity and intelligence. Sensitivity to the unique geography, history, and local community of each city, and intelligence in inte- grating new climate patterns in the design, to mitigate their effects. They were developed by multidisciplinary teams composed of experts from academic and non-academic institutions.

They are presented through drawings, including maps and diagrams. The outline of the line, that holds together the solution. Drawings are a universal language that preceded the written word. The ideas illustrated in the five selected projects presented in the book are fundamentally the result of site-specific conditions. The approach itself is multidisciplinary, based upon many different schools of thought. They merge the gap between the material and the functional, the pragmatic and the imaginary/visionary looking at the important structures and signs of the problem from the perspective of discovering how they relate to collective activity.

Each design proposal emerges from the methodology adopted. When experts holding complementary disciplines are engaged in dialogue, at first there is a moment dominated by a cacophony while facing a complex number of parameters that need to be combined. It is chaotic and unpredictable before reaching a common ground. Ideas are shared in a cross-pollination of visions among partners from public and private, academic and non aca- demic sectors in different countries.

The problems and threats are real and expanding rapidly. Solu- tions emerge from dialogue; they are creative and depend on the combination of such interdisciplinary fertile discussion. Coming from various fields of knowledge, each contribution has its own perspective and need to combine each expertise to the common vision. The formula that sustains each of the five projects succeeds to expand new perspectives and discovers new ways of designing that cannot be described in words alone. Only multidisciplinary teams composed of open-minded experts could develop such per- tinent, sustainable and inclusive design.

The richness of the solutions presented is the result of a dialogue process, which opens up new alternatives also useful for other european cities. The proposals aim to build new infrastruc- tures that integrate nature, and its ecological systems, instead of trying to limit and control. They promote solutions where there is a dialogue relationship rather than a power relationship over climate manifestations. The names assigned to the five projects reflect this perspective: “Vine as a Spine” in the Metropolitan Area of Lisbon, “A leaf on the water” in Gdansk”, Let it Ti(be)r” in Rome, “The Arc” in Stockholm and “Clean the soil” in Thessaloniki. All share an innovative approach, promoting contemporary strategies for urban resilience. They are inspired by the geomorphologic conditions of each waterfront area, regarding their transformations by industrial-ization, throughout the 20th century.

The content produced for this book is the result of a wide international collaboration, aiming to share a body of knowledge through text and drawings. In times of uncertainty, researches have followed a methodology that has been useful for the scientif- ic community, and can be extended to stakeholders, decision makers and to the general public interested in waterfront cities facing climate change. The Sustainable Open Solutions (S.O.S) presented within this publication are different from the common S.O.S mean- ing (Save Our Souls), which is normally associated with a last call for help. Instead, the premises of the research carried out privilege successful initiatives to highlight positive ideas that may build an inspiration for the future.

Introduction

The waterfront of Stockholm, one of Europe's fastest-growing cities, stands at the forefront of climate change challenges. As such, there is a pressing need for innovative solutions and resilient urban design. The SOS Climate Waterfront research project gathered international experts and local representatives, coming from different disciplines to work together in May-June 2022 to discuss, explore proposals and design Sustainable Open Solutions (SOS).

This book explores three urban sites in Stockholm, holding significant implications for the city's waterfront— Lövholmen, Frihamnen, and Södra Värtan. During the workshop, SOS Climate Waterfront participants, mainly European researchers, analyzed future challenges, raised new questions, and depicted solutions, which can now contribute to cross-country comparisons in a larger EU-framework.

The three sites are not only driven by the demand for more housing but also face crucial issues related to cultural heritage, climate change, landscape ecology, and social development. Achieving a delicate balance between these aspects and economic interests presents a significant task for the city. The waterfront of Stockholm holds substantial relevance in the context of climate change and its impact on coastal areas. Thus, analysis of the Swedish context, based on data collected and on-site knowledge sustains a deeper understanding of the challenges and opportunities that lie ahead.

Stockholm is expected to be affected by the impacts of climate change, including temperature increases, changing precipitation patterns, and the potential for more frequent cloudbursts. While the rising sea level is a long-term challenge rather than an immediate concern, increasing risks of extreme weather events and flooding were taken in consideration.

Stockholm rests on two different bodies of water, at a location where the Baltic Sea (Östersjön in Swedish) with brackish water meets Lake Mälaren, which is an important provider of freshwater for the larger Stockholm area. As the lyrics of a popular contemporary Swedish song (by Robert Broberg) describe it: “the city is full of water”. However, to ensure that the ecological and chemical status will be maintained, in facing future challenges in terms of urbanisation and climate change, much attention has been paid to ensure the preservation of the water quality of the Mälaren Lake, a vital water source for two million people.

The city values its water and continuously invests in improving the situation (e.g. the new sluice at Slussen). The activities carried out in the SOS Climate Waterfront workshop in Stockholm integrated this relationship to water as well as the continuing land-rise, the balance of which adds complexity to the sea level modelling and therefore also to the anticipations and scenarios for the future.

In this book, the authors explore innovative strategies and design proposals to tackle these challenges while preserving the cultural identity and heritage value of the sites. Researchers from various European cities, supported by experts and academic lectures, analyze extensive input materials and information, ranging from planning documents and historical records to consultation reports and city visions. By drawing upon multidisciplinary backgrounds and experiences, the researchers identify the socioeconomic and environmental qualities of each site, ultimately developing site design concepts and solutions that address climate change challenges, the maintenance of cultural identities, and the protection of biodiversity.

Throughout the book, the proposed designs emphasize the importance of finding a balance between preserving cultural heritage, the values of local communities, the stimulating economic growth, and promotion of sustainable urban development. Key elements include the reuse of existing infrastructure, the integration of green-blue schemes, the improvement of biodiversity, and the creation of vibrant and multi-functional neighbourhoods that connect people to each other and their surroundings.

While design solutions present promising approaches, their implementation and the institutional challenges that may arise in specific city contexts remain external to the results presented here. The book acknowledges the need for further research and highlights the shared recognition among the workshop participants regarding the gaps and blind spots in their findings.

The following chapters of the book delve into climate change in Sweden, the role of culture and arts in the environmental movement, and specific case studies and design proposals for each site. By exploring these diverse perspectives, this book aims to contribute to the ongoing discourse on sustainable urban design and planning, to inspire innovative approaches in addressing complex challenges faced by Stockholm in the future.

PART 1 of the book offers a comprehensive understanding of climate change in Sweden, street fishing in Stockholm, and the role of culture and arts in the environmental movement in the Nordic Region and internationally. Furthermore, the lessons from Stockholm and its surroundings in this report draw on presentations, by professionals and researchers from various fields, made during the workshop. Some of these lessons have been written into interesting articles, introduced below.

The chapter “Climate change in Sweden” by Magnus Joelsson from the Swedish Meteorological and Hydrological Institute (SMHI) provides an updated analysis with data and the context for discussing climate change in Sweden. The text makes the distinction between weather and climate, referring to the expression “Climate is what you expect, weather is what you get” that Mark Twain is said to have coined. Moreover, calling for actions by emphasising that the trend of climate change is expected to continue, both globally and in Sweden. What will happen in the far future still depends on our actions, now and in the future.

The contribution entitled “Urban nature does not stop at the waterfront, neither should urban planning, a case study of street fishing in Stockholm” raises questions about how planning and strategies for waterfront areas in cities should consider more perspectives from a wider group of interests. It discusses how urban dwellers live with water, with a focus on recreational fishing and what this use entails. The authors (Anja Moum Rieser, from KTH Royal Institute of Technology, Wieben Johannes Boonstra and Rikard Hedling, both from Uppsala University) go beyond the human-centric view and expand the gaze to other species’ needs and also incorporating the body of water in planning for the urban waterfront areas.

The chapter “The role of culture and arts in the environmental movement in the Nordic Region and internationally” by Elisavet Papageorgiou and Iwona Preis from Intercult, discusses artistic perspectives on sustainability and climate change. This focuses on how art and culture can raise awareness, provide inspiring actions, and promote social cohesion around sustainable practices. Drawing on experiences from projects aiming to invite and engage community dialogues, they argue that artistic strategies can challenge dominant narratives and promote alternative visions for a sustainable future.

The contribution “Sense the Marsh” by Thelma Dethelfsen from KTH The Royal Institute of Technology, emphasises the importance of architecture and landscape design in creating adaptive and resilient strategies to manage flooding and sea level rise. The study focuses on how designs can encourage interaction and awareness with the surroundings. Thereby highlighting the interfaces between humans and nature and raising questions about how flooding can be used as a quality and catalyst to attract more people to an area. The resulting design provides an opportunity to experience nature though the design and architectural solutions, situated on the border between human, non-human species and nature.

In PART 2, readers will explore the detailed design proposals developed by different groups for the urban sites in focus. These proposals aim to intertwine sustainability, cultural identity, and economic interests, offering insights into the potential for resilient and vibrant urban spaces.

By assessing existing conditions on three sites analysed in Stockholm, including Lövholmen, Frihamnen, and Södra Värtan, the teams participating in the workshop actively contributed to the analysis of the sites and development of design solutions for the areas, in the end forming strategies for better preparedness for future challenges and better lives for the inhabitants.

Lövholmen is located in the north-western part of Liljeholmen, one of the major developmental centres in Stockholm. The area is currently a closed-off industrial site, but the municipality’s intention is to redevelop it into a mixed urban space with homes, workplaces, shops, schools, and more. It's expected that 1500 new homes will be built in the area. Many of the current industrial buildings are empty and in bad shape. While some of these will be replaced with housing, other industrial buildings have heritage value and should be protected during the development, after which a new use should be found for them. Frihamnen is, together with the Södra Värtan project, part of the larger development of ”Norra Djurgårdsstaden”, the Stockholm Royal Seaport. Frihamnen is located to the south of Värtahamnen and is in turn strongly connected to Loudden in the south. The municipality plans for the area to contain approximately 1700 homes, 4000 workplaces and 75,000 m2 of retail and office space. Some of the existing businesses in Frihamnen will remain, but much of the existing infrastructure is planned to be removed. The harbour no longer handles freight shipping, but passenger ships will continue to depart from the harbour (Frihamnspiren).

Södra Värtan is planned to contain 1500 apartments, 20 preschool departments, 155,000 m2 of office and retail space, as well as 10,000 m2 of parks and a 600 m long waterfront walkway. The new development is intended to co-exist with the activities in the harbour, which creates challenges such as the blocking of noise stemming from the cruise ships. The walkways along the waterfront are planned to have shops and restaurants.

The contributions of the articles, together with the SOS Climate Waterfront teams’ analysis of the three sites in Stockholm, provides relevant and timely interdisciplinary efforts to co-create novel solutions and future strategies to manage the climate challenges ahead.

The solutions relate to the history of the urban territory, actors involved (or those excluded) and changes, over time, of planning ideals. A key theme is how to plan by creating inclusive strategies for the future by involving representatives of diverse interests, competences, and future visions for the sites. The consequences of climate change are affecting these different stakeholders and citizens in a wide range of ways, so including them in the process is crucial. This also includes the inclusion of future generations’ views on urban transformation. The largest challenge is to create new, novel solutions where these human interests, as well as those of local nature and non-human species, can be incorporated, in an effort to plan and design for a mitigation and management of the consequences of climate change.

As we embark on this journey of exploration and innovation, we invite readers to delve into the pages of this book, where interdisciplinary research, creative design, and a shared commitment to sustainable urban development and decarbonisation strategies converge. Together, let us envision a future where cities thrive, harmoniously balancing their heritage, environment, and economic aspirations.

The term nature-based solutions (NBS) has gained traction in recent years and has been applied in many settings. There are few comprehensive assessment frameworks available that can guide NBS planning and implementation while at the same time capturing the short- and long-term impacts and benefits of the NBS. Here a recently presented framework, which builds on the theory of change and was developed to assess NBS at different phases of the project cycle, was applied to seven diverse case studies. The case studies addressed water quality and quantity issues in peri-urban areas across the global north and south. Framework indicators covering the sustainability dimensions (environmental, social and economic) were assessed at three stages of the framework: context, process and results. The work sought to investigate the following research objectives: (1) Can this framework be robust and yet flexible enough to be applied across a diverse selection of NBS projects that are at different phases of the project cycle and address different kinds of water challenges within varied ecological, social and economic contexts? (2) Is it possible to draw generalisations from a comparative analysis of the application of the framework to the case studies? Results showed that the framework was able to be applied to the case studies; however, their diversity showed that NBS projects designed in one context, for a specific purpose in a specific location, can not necessarily be transferred easily to another location. There were several process-based indicators that were universally significant for the case studies, including expertise, skills and knowledge of the involved actors, roles and responsibilities of involved actors and political support. The result-based indicators were case study-specific when environmental indicators were case study-specific, and important social indicators were environmental identity and recreational values. Overall, the use of the framework benefits the recognition of the implementation's advances, such as the change in context, the processes in place and the results obtained.

Recent efforts to achieve social, economic, and environmental goals related to sustainability emphasize the importance of nature-based solutions (NBS), as grey infrastructure alone is insufficient to address current challenges. The majority of frameworks proposed in the literature fail to address the full potential of NBS, neglecting long-term results, unintended consequences, co-benefits, and their contribution to achieving global environmental agreements, such as the Agenda 2030, especially for water management in a peri-urban context. Here we present an innovative framework that can be applied to both NBS project planning and evaluation for several water-based challenges, giving practitioners and researchers a tool not only to evaluate ongoing projects but also to guide new ones. The framework considers three main stages of a NBS project: (1) context assessment, (2) NBS implementation and adaptation process, and (3) NBS results. This tool has the potential to be used to evaluate whether NBS projects are aligned with sustainability dimensions through a set of adaptable sustainability indicators. The framework can also highlight how the NBS targets are related to the sustainable development goals (SGD) and contribute to catalyzing the 2030 Agenda. The framework is an important tool for water management and other NBS types.

Nature-based solutions (NBS) represent the most recent of several "greening" concepts proposed to support spatial planning and decision-making towards sustainable metropolitan regions. Despite similarities, the concepts stem from different disciplines and policy arenas and reflect various models of people-nature relations. This paper aims to analyze the uptake of greening concepts in scientific planning literature focusing on (urban) nature and landscape in the metropolitan region of Stockholm, Sweden, over the last three decades. It investigates what changes this evolution has brought in terms of the topics adopted, methods applied, and types of planning support put into practice. We identified 574 articles that reflect substantial research on greening concepts in the Swedish planning context. The articles demonstrate an initial prevalence of biodiversity with later increases of interest in ecosystem services and NBS. A detailed analysis of the studies focusing on Stockholm revealed Population growth/densification, Green space management and Biodiversity conservation as the most commonly addressed societal challenges. The most frequently mentioned type of green and blue element is Parks and (semi-)natural urban green areas, including urban forests. Methods applied were mostly quantitative, while mixes with qualitative approaches were only apparent in ecosystem services articles. Half of the studies involved practitioners or decision-makers, but only four seemed related to real-life planning processes. Taken together, the influence of scientific literature on the uptake of greening concepts in spatial planning seems to have been limited. Future mainstreaming of greening concepts in Stockholm and beyond could benefit from available data, methods and experiences, but will require more active translation and boundary management. Further research into science-policy-planning interfaces at city scale is thus imperative to advance more sustainable pathways for people and nature in metropolitan regions.

Landscape approaches are important for planning of urban sprawl in peri-urban landscapes, continuously emerging in many metropolitan regions. In the case of Stockholm Region, land-take and incremental urbanisation is a continouous process, while the regional development plan has ambitions to steer the overall development in a sustainable direction. This plan contains a green infrastructure effort building on a set of green wedges, mainly serving as support to the needs of the city and suburbs and their citizens. This initiative differ from the later green infrastructure action plan provided by the county administrative board, related to the EU biodiversity strategy and guidelines. The latter has a different approach, mainly targeting biodiversity goals as well as ecosystem services. These approaches differ from each other in several ways while both have unclear roles when it comes to municipal planning on different levels. Furthermore, the municipalities have their own initiatives when it comes to green infrastructure and nature-based solutions and it is not clear how the different planning tiers are linked to each other, to planning and management, and to multifunctional landscapes. The aim of the REPLAN project is to investigate how the different green infrastructure initiatives are linked to planning, to each other on different scales, and whether they can serve multi-functional landscapes when it comes to biodiversity and different ecosystem services. The REPLAN project involves stakeholders and practitioners on different planning levels for co-producing knowledge, methods and strategies for green infrastructure and nature-based solutions to serve as tools for sustainable transition of metropolitan areas and their peri-urban landscapes.

The need for a transformation from conventional rainwater drainage systems towards Blue Green Infrastructure systems, designed as open spatial systems for sustainable rainwater management, is acknowledged. However, these systems are viewed as sociotechnical systems and, consequently, this transition has been slow. This paper focuses on the planning processes behind Blue Green Infrastructure projects in Stockholm and analyse them as transition experiments, addressing the question: what challenges and opportunities can be identified to enable the new systems to become a common component of rainwater management practices? Based on a literature review, this paper presents a methodological framework by identifying the key factors for facilitating or blocking sociotechnical change. These cluster around six categories ?? context, actors, instruments, processes, outputs and outcomes, and impacts. The paper used the framework to collect data and analyse three urban projects. Stockholm has remarkable strengths associated with moving towards new solutions, in terms of receptive contexts, human agency, space for experimentation, and a collaborative planning culture. However, there is a need for renegotiating the positional power of the actors involved in the planning systems in order to provide opportunities for water professionals to establish a stronger role in fitting the new solutions into the overall landscape, and urban planning processes and goals.