Green and blue infrastructure empowers local governments to design the high-quality integrated urban systems of tomorrow

In the fight against climate change, combining Green and Blue Infrastructure (GBI) planning strategies with urban systems integration is a promising strategy for reducing carbon emissions and waste production whilst strengthening cities’ ecosystem services. In particular, GBI is well suited for integrating food, water and energy into a single system called the Nexus. Creating the Nexus will increase efficiency and reduce environmental strains. The IFWEN project therefor fills an important knowledge gap by demonstrating which types of GBI and ecoservice are connected, as well as showing policy-makers how GBI can be used as an instrument for transformative change.

Why is a global study of GBI useful and why is it a good tool for urban systems integration?

As a part of the SUGI FWE NEXUS call, funded by JPI Urban Europe and Belmont Forum, IFWEN (Understanding Innovative Initiatives for Governing Food, Water and Energy Nexus in Cities) had partners spanning North and South America, Europe, Africa and Asia. This put the project in an exceptionally strong position to analyse global and regional trends in GBI usage. A global approach is not only advantageous for researchers but also policy makers. It offers policy makers a starting point for understanding how GBI can achieve the dual goals of increasing efficiency in delivering urban services at low-cost whilst meeting national and international climate commitments. It does this by giving them a clear and comprehensive overview of the climate-friendly benefits of GBI, called ecosystem services or ecoservices, and demonstrating how within a well-designed system, ecoservices could be tailored to tackle a range of issues, including flooding and food insecurity. 

However, the first thing IFWEN’s work does is show decision-makers why GBI is a natural fit for urbans systems integration. GBI is rooted in using nature-based solutions for urban development, and since nature does not recognise man-made boundaries, nature-based solutions naturally tend to impact multiple urban systems. Urban agriculture, for example, in its efforts to increase food security will always impact water and energy as well. So, if GBI is consciously and carefully used in urban systems integration, it could be a strong tool for making the Nexus both well-optimised and environmentally friendly.   

Since nature does not recognise man-made boundaries, nature-based solutions naturally tend to impact multiple urban systems.

The project’s coordinator, Jose A. Pupim de Oliveira, says the global scope of the project has produced three key outputs. The first is a broadly applicable conceptual framework to guide decision-making processes, helping policy makers identify the advantages and trade-offs of distinct types of GBI and mitigating the potential risks of using GBI when designing for urban systems integration. The second output is an extensive review of GBI trends across the world, showing decision makers where GBI innovations are occurring and what kinds of problem they can tackle, giving them key insights into how it is being underutilised. Lastly, the project has produced a model showing the types of learning mechanisms that policy makers need to adopt to bring about transformative positive change when using GBI.

A conceptual framework to guide decision-making for more integrated and resilient cities

IFWEN’s conceptual framework is designed to help policy makers clearly understand the positive and negative impacts of different types of nature-based infrastructure. Besides demonstrating risks and benefits, the framework shows the kinds of ecoservices that different types of natural infrastructure produce and their relevance to nexus building. For example, the visual representation of the framework (shown below in Figure 1) demonstrates that street trees (planting trees along streets) provide a natural cooling service, decreasing energy demand for building refrigeration. The framework also highlights the degree of connectivity between each nexus element (food, water and energy) and their relationship with seven distinct types of GBI (shown in the left column titled GBI in Figure 1). For instance, it shows that urban energy systems are connected to multiple types of GBI, whereas urban food primarily connects to a single form of GBI, urban agriculture. 

Figure 1: A visual representation of the conceptual framework

IFWEN’s analysis of GBI’s effects on the Nexus, published in the Journal of Clear Production, shows that these effects are heterogeneous across global cities, varying according to their size, income and geographic location. The paper highlights the positive transboundary effects of different GBI on food, water and energy systems, thus emphasising the importance of integrated planning. This is key to optimising synergies and reducing trade-offs in urban GBI design and implementation, with positive multiplier effects on local and regional food, water and energy resources.

A review identifying GBI trends in developing countries and centres of innovation

The project also carried out an extensive analytical review of GBI research in 120 cities from across the world, identifying trends and innovations in developing countries. The global scope of the review and its focus on developing countries was especially important since two-thirds of the world’s population currently live in these countries. Mitigating climate change will depend heavily on the trends adopted in urban centres within these middle-income countries. So, good GBI practises found within one of them is likely to be widely applicable and beneficial to sustainable development. The review shows that GBI is still overlooked as a development strategy. Nonetheless, existing GBI scholarship does reflect regional concerns. For instance, 34% of GBI research in Africa focuses on urban agriculture. This is unsurprising as food security and employment are significant concerns within the region. On the other hand, 42% of the research in Asia focuses on green spaces and 22% on green infrastructure, reflecting spatial planning and land distribution concerns within the region’s high-density cities. Correspondingly, in Latin America and the Caribbean, where there are serious inequality issues, GBI research addresses problems such as environmental justice. 

GBI’s potential for regional development is underutilised

IFWEN’s analysis also shows that GBI’s potential for regional development is currently being underutilised. For instance, despite flooding and water sanitation being critical issues for Asia’s high-density cities, academic research favours conceptual models such as Flood Risk Management (FRM) and Water Sensitive Urban Design (WSUD) over GBI solutions. These concepts are not applied within an integrated perspective, such as the Nexus, overlooking GBI’s emphasis on multifunctionality and connectivity. In this regard, China stands out as an exception. 16% of GBI research in China focuses on the novel Sponge City concept. The concept adopts a holistic approach, connecting green spaces and waterways to create cities that benefit from several environmental services. These services include absorption capacities that simultaneously reduce the urban heat island phenomenon, improve water sanitation and decrease the risk of flooding. 

Uncovering the importance of sectoral diversity in creating transformative change

Another project goal was to discover what kind of government learning could make GBI an efficient strategy for transformative change. The research analysed data from 82 cities spanning 30 countries using statistical modelling. The result was a model showing statistically that internal local government learning mechanisms, such as hiring expertise or internal training, are only positively associated with incremental change. Whereas external learning mechanisms, like training delivered by NGOs and research produced by universities, are significant in producing transformative change. 

When there is no sectoral diversity, external learning has a negative impact on transformative change.

Notably, the model also shows that when there is no sectoral diversity, external learning has a negative impact on transformative change. Sectoral diversity refers to collaborations between public, private and non-governmental organizations. Directly, external learning mechanisms have a statistically negative impact on the possibility of local governments learning from GBI research and producing transformative change. However, this negative impact is neutralised by an increase in the sectoral diversity of stakeholders involved in a GBI project. Jose elaborates that the nature of GBI requires “specialists of all kinds to come together, so it makes sense that increased sectoral diversity is more likely to bring the best out of GBI.”

Global impact showing how GBI can empower local governments

ICLEI’s (Local Governments for Sustainability) participation in the IFWEN project means that the project’s results will be disseminated on a global scale. ICLEI is a transnational network of local and regional governments with over 2,500 members representing local governments in over 125 countries. ICLEI will disseminate the project’s guidelines for developing GBI projects focused on nexus building, along with its other findings. This partnership has also led to the creation of eight case studies for each of IFWEN’s partner cities, contributing to a greater understanding of GBI and nexus interactions. These case studies identify the capabilities and potential for innovative nexus approaches and offer lessons for future implementation. All eight case studies are freely available online.

IFWEN’s work has been fruitful enough to produce sustained momentum beyond the initial project. Having secured a Take-It-Further grant from PEGASuS (Program for Early-Stage Grants Advancing Sustainability Science), the project will work with GLOCULL (another project from the SUGI/NEXUS call) to pair eight cities together for mutual learning objectives. Jose says, “this means cities like Sao Paulo in Brazil can learn from Gangtok in India about effective composting, and Gangtok can learn about marketing urban agricultural goods from Sao Paulo.”

GBI presents local governments with tools for combating climate change, since GBI is about land use (unlike energy provision) it is usually determined directly by local governments.

The key point Jose makes about the project is that it is the first long-term effort to properly examine the impacts of GBI on nexus building. This project has shown that GBI offers opportunities to build more robust interconnections between food, water and energy systems. GBI also presents local governments with tools for combating climate change, since GBI is about land use (unlike energy provision) it is usually determined directly by local governments. Jose gives an example in São José dos Campos, where the municipal government does not control the food market and a state company is responsible for water provision, but the local government does have leverage on land use, which they are aiming to use to build more climate-friendly and integrated urban systems. Finishing on the big picture objective of the project on finding innovations and trends, Jose says, “our work shows that you do not always need rocket science to solve these problems; there are low-tech solutions available. We need to make sure they are not the exception.”  




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