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Flip the City

Basic information

Project Title

Flip the City

Full project title

Flip the City: Making circular pavement tiles made from duckweed that grow into biodiverse greenery

Category

Shaping a circular industrial ecosystem and supporting life-cycle thinking

Project Description

Flip the City makes biodegradable tiles created from duckweed, an abundant aquatic plant in the Netherlands. With the same dimensions as standard pavement tiles, these circular, biodiverse duckweed tiles allows anyone to easily "flip" their grey surroundings into flowering greenery. Made locally and designed to nurture native species, duckweed tiles revive biodiversity one flip at a time.

Geographical Scope

Regional

Project Region

South Holland, Netherlands

Urban or rural issues

It addresses urban-rural linkages

Physical or other transformations

It refers to a physical transformation of the built environment (hard investment)

EU Programme or fund

No

Description of the project

Summary

Flip the City aims to transform grey, paved areas into biodiverse green spaces by creating biodegradable 'kroostegels' or duckweed tiles. The tiles are made locally from duckweed, an aquatic plant that is becoming overgrown due to climate change and artificial fertilisers. This disturbs and suffocates aquatic life in the Netherlands. The tiles contain a special seed mix that will grow into native flowers and plants, attracting biodiversity.

As 50% of all gardens in the Netherlands are filled with concrete tiles (Natural Biodiversity Center, 2019), this project is aimed at individuals who want to green their surroundings and municipalities & organisations that manage public spaces. By replacing standard concrete paving tiles with Kroostegels, anyone can easily transform urban areas into more natural, thriving ecosystems, while learning about native Dutch biodiversity.

In this respect, kroostegels integrate the NEB values of beautiful, sustainable, and inclusive. Our tiles beautify neighbourhoods with flowering biodiversity, provide a sustainable and circular solution to abundance of duckweed, and are inclusive by making biodiversity restoration efforts accessible to all.

In the long term, Flip's mission is to facilitate the widespread use of kroostegels across the Netherlands: to help restore biodiversity, mitigate urban flooding and the heat island effect, while tackling the nitrogen problem and bringing communities together to participate in the transformation of their living environment. Our project promotes circular thinking by transforming a current problem in Dutch waters into a solution for urban greening. Flip does this together with municipalities and its citizens by establishing a circular chain on a local level.

Each tile sequesters over 1600 grams of CO2, grows 31 species of plants, removes 45 grams of nitrogen from water, cleans 3m2 ofwater surface and can support 996 unique pollinators.

Key objectives for sustainability

Sustainability is central to the mission of Flip the City. Our project aims to create closed-loop systems that eliminate waste, regenerate ecology, and foster thriving communities. Flip the City works to achieve sustainability in the following ways:

- Circular materials: Kroostegels transform an abundant aquatic waste material, duckweed, into a valuable product that regenerates the environment. This circular approach eliminates waste and gives new life to an underutilized resource.
- Local and seasonal: Kroostegels are made using duckweed harvested from local waterways during seasonal overgrowth. This reduces transport emissions and supports the local economy.
- Restoring ecology and climate proofing: By replacing impervious surfaces with biodiverse, flowering tiles, kroostegels help restore damaged ecosystems in cities. This improves soil health, water drainage, microclimates, and biodiversity.
- Quantified impact: Each kroostegel makes a measurable positive contribution by sequestering carbon, absorbing nitrogen, increasing pollinators, and more. This allows us to continiously quantify our sustainability impact.
- Community participation: Kroostegels empower people to directly improve their surroundings. This fosters community buy-in and awareness of sustainability challenges like biodiversity loss and climate change.
- Accessible and inclusive: With our simple tile-for-tile swap, kroostegels make greening easy and accessible for all. This allows more equitable participation in sustainability efforts.

By innovatively diverting a waste stream into an ecological regeneration tool, Flip the City demonstrates how creative thinking can produce scalable systems-change. The project meets key sustainability objectives like waste elimination, ecosystem restoration, and community resilience. As it expands, Flip the City provides an exemplary model of local, circular sustainability.

Key objectives for aesthetics and quality

Aesthetics and human experience are central in the design and impact of kroostegels. Flip the City has developed the kroostegels to beautifully transform neighborhoods while creating rewarding experiences for communities. This is achieved through:

- Co-creative design process: The kroostegel design integrates input from diverse partners like industrial producers, government agencies, and citizen end-users. This human-centered approach results in an aesthetically pleasing, but also easy to manufacture, product that meets people's needs.
- Dynamic transformation: Unlike static masonry, kroostegels offer the experience of giving citizens the ability to witness nature grow and change with the seasons. This creates an engaging, but also educative living environment.
- Rewarding cultivation: Those using kroostegels can actively participate in greening through watering, pruning, customization, etc. This allows for a rewarding creative experience. We also offer custom seed mixes for specific regions
- Local relevance: Region-specific seed mixes in each kroostegel give people the opportunity to revive native flora. This connects to local heritage and identity.
- Ease of use: With our simple tile-for-tile swap, kroostegels make installing and maintaining urban biodiversity highly accessible and easy to use. This expands our participation efforts.

By facilitating creative personal connections between people and nature in cities, Flip the City provides an inspirational model for harmonious, human-centered design. The project's exemplary leveraging of aesthetics and experiential quality fosters community pride, stewardship, and belonging.

Key objectives for inclusion

Flip the City aims to make greening and sustainability as inclusive and accessible as possible. Key objectives supporting inclusion include:

- Affordable products: Kroostegels are priced competitively (€10,-) compared to other greenery options (moss of the same dimensions cost easily €50,-), with the goal of maximizing adoption. This enables people across most income levels to participate.
- Inclusive production: The manufacturing process involves partnerships with social enterprises and works completely locally per region. This spreads economic benefits inclusively.
- Locally-tailored solutions: Tile seed mixes are specially designed to suit each region’s climate and ecology. This allows broad accessibility across diverse geographies.
- User-friendly design: With our simple tile-for-tile swap, kroostegels are designed for easy DIY installation by anyone. This makes urban greening highly accessible.
- Collaborative governance: Flip the City co-designs solutions with diverse stakeholders including municipalities, businesses, non-profits and citizens. This facilitates inclusive decision-making.
- Scalable model: The decentralized production model enables replication across communities, allowing broad access to sustainability benefits. We’re currently expanding our efforts throughout the whole of the Netherlands

By empowering people across society to directly participate in greening their environments, Flip the City provides an exemplary model of inclusion. The project decreases barriers through affordable pricing, collaborative processes, and human-centric design, enabling a just transition for all.

How Citizens benefit

Flip the City has pursued an inclusive, collaborative approach that engages citizens, communities, and civil society organizations in multiple ways:

- National media coverage has helped spread awareness of the kroostegel concept to the general public across the Netherlands. This has helped us spark interest and ideation around urban greening and biodiversity restoration efforts.
- Partnerships with municipalities, water authorities, provinces, schools, and other entities facilitate pilot projects, local duckweed sourcing, and research. This has enabled a localized implementation and impact approach.
- Outreach to neighborhood associations, environmental groups, and community centers promotes grassroots participation in greening initiatives using kroostegels. This has driven community buy-in.
- Seeking input from end users on tile design and functionality ensures the product meets local needs and preferences.

This multi-stakeholder involvement at national, regional, and local levels is key to Flip the City's model of creating shared value. By actively engaging citizens and partners, the project builds awareness, garners support, empowers change-makers, and ultimately drives scale and impact across society.

Physical or other transformations

It refers to a physical transformation of the built environment (hard investment)

Innovative character

Flip the City prides itself on 3 key innovative aspects:

1. Quantified sustainability impact. Detailing measurable positive effects per tile across categories like carbon sequestration is innovative among biodiversity restoration efforts
2. Leveraging natural processes for sustainability. Allowing the tiles to biodegrade over time and nourish native plants is an innovative way of working in concert with natural systems, while also using the eutrophied waters of the Netherlands to collect duckweed that cleans up the water - a systemic approach.
3. Transforming an abundant waste material into a regenerative product. Converting rapidly growing duckweed from a nuisance aquatic weed into a circular tile material is a novel waste-to-resource approach uncommon in mainstream greenifying efforts.

Disciplines/knowledge reflected

Flip constitutes highly cross-disciplinary approach, from its founders to collaborations:

- Biology/Ecology: Experts assisted in identifying optimal native plants and seeds for each region and climate. This ensured that the tiles promote biodiversity in a sustainable way.
- Engineering: Engineers advised us on the tile composition, durability, manufacturing processes, and automation. This enabled effective production scaling.
- Design: Product designers shaped the tile form factor, visual aesthetics, and end user experience. This made the product appealing and user-friendly.
- Business: Strategists assisted in developing partnerships, distribution models, marketing, and funding opportunities. This helped bring the concept to market.
- Public Policy: Government entities provided insights on regulations, municipal procurement, and local needs. This facilitated public adoption.
- Sustainability: Experts guided materials selection, circularity, and impact measurement. This aligned the project with green goals.
- Social Sciences: Students as behavioral experts advised us on the benefit of community activation and engagement tactics. This has driven grassroots participation.

Regular cross-disciplinary workshops and collaborations ensured continuous integration across fields. By combining expertise in biology, engineering, design, business, policy, sustainability, social science and more, Flip the City is able to develop holistic nature-based solutions tuned for real-world implementation.

Methodology used

Flip the City has taken an iterative, systemic, and entrepreneurial approach towards creating kroostegels

- Iterative development - The project evolved through three years of testing and refinement in partnership with users, experts, and stakeholders. This allowed continuous improvement of the product, business model, and implementation strategy based on real-world feedback.
- Systems thinking - Kroostegels are designed holistically, recognizing how elements like materials, partnerships, distribution, employment, and public policy are interconnected. This enabled a systemic approach to sustainability.
- Circular design - Following circular economy principles, the tiles transform waste into value, regenerate ecology, and are loc ally produced, used, and composted. This eliminates externalities.
- Entrepreneurialism - Leveraging partnerships, market-based funding, and communications outreach drove adoption. This balanced purpose and viability for scalability.
- Research-backed - Scientific studies by partner universities quantified the tiles' environmental benefits. This validated the evidence-based approach.
- Community co-creation - Collaborating with local citizens, associations, job programs etc. tailored solutions to needs and gained buy-in. This ensured inclusive development.
- Interdisciplinary - Integrating diverse fields of biology, design, business, policy and more created holistic solutions. This bridged science, enterprise, and community.

By taking an adaptive, collaborative methodology combining research, business principles, and stakeholder participation, Flip the City was able to develop replicable systemic solutions optimized to revitalize communities and nature.

How stakeholders are engaged

Flip the City has taken an inclusive, collaborative approach to engage diverse stakeholders:

Local level:

- Neighborhood associations and municipality action groups helped promote local greening initiatives using kroostegels. This drives hyperlocal community participation.
- End users gave input on tile design and functionality. This ensured the product meets on-the-ground needs.

Regional level:

- Partnerships with municipalities and water authorities enabled pilot projects, tile distribution, and duckweed harvesting. This facilitated localized impact.
- Students from applied sciences schools and universities assisted us with research and development. This brought about specialized technical expertise and new ideas regarding supply chain models for duckweed.
- Collaboration with social enterprises drove scale in manufacturing and distribution. This expanded impact.

National level:

- Media coverage raised broad awareness across the Netherlands. This sparked nationwide interest and ideation.
- Engaging public entities like provinces provided funding opportunities. This enabled growth and sustainability.

Our multi-level involvement with stakeholders brought critical resources, knowledge, promotion, and legitimacy at each stage of the project. By actively engaging diverse stakeholders, Flip the City is able to design specifically localized solutions while also driving broad adoption for national impact.

Global challenges

We quantify our solution by looking to which sustainable development goals we contribute to:

1. Biodiversity - Local solution: Transforming grayspaces into ecosystems with native plants helps restore biodiversity in cities (SDG 15, 11).
2. Water Management - Local solution: Allowing drainage through tiles reduces flooding risk and replenishes groundwater (SDG 6, 11).
3. Climate Resilience - Local solution: Evaporative cooling and carbon sequestration mitigate urban heat island effects and emissions (SDG 13, 11).
4. Water Quality - Local solution: Duckweed harvesting improves water quality by removing excess nutrients (SDG 14, 6).
5. Circular Economy - Local solution: Tiles repurpose waste into regenerative materials, demonstrating circular principles (SDG 12, 9).
6. Local Economy - Local solution: Sourcing duckweed and production locally provides jobs and community benefits (SDG 8, 11).
7. Education - Local solution: Tiles raise awareness of ecosystem processes and sustainable solutions (SDG 4, 15).
8. Carbon Sequestration - Local solution: Duckweed sequesters CO2 at rates exceeding forests, then tiles store carbon (SDG 13, 15).
9. Nutrient Capture - Local solution: Duckweed absorbs excess nitrogen and phosphorus in waterways (SDG 12, 15).

By tackling these interconnected environmental, economic, and social challenges locally, Flip the City contributes to a more sustainable future globally.

Learning transferred to other parties

There are several key elements of our Flip the City project that make our project transferable and replicable across contexts and borders:

- Circular tile material - The technology of transforming locally harvested duckweed into biodegradable tiles can be replicated in regions where duckweed is prevalent. This can extend beyond the scope of the Netherlands, into regions like France and Germany
- Co-creative design process - The methodology of co-designing solutions with citizens, experts, and stakeholders can be applied in diverse contexts to drive further inclusive innovation. We’re currently looking at using our methodology for the design of new renegerative products
- Communications strategies - The awareness, education, and marketing approaches are essential to our company: we focus on being as transparent as possible to inspire other circular entrepreneurs and customers to grow biodiversity or build similar systemic circular design solutions.
- Hyper-localized production - Our kroostegels can be made anywhere! The simplicity of using duckweed and creating our tile allows for a distributed manufacturing model which can easily be adopted into localized facilities and labor is replicable across scales. We’re currently producing in our own small workplace in South Holland, but are actively looking to extend this across regions into workplaces for people with distance to the labor market.

Keywords

Biodiversity
Sustainability
Circular Economy
Urban Greening
Community Engagement

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