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Berlin, Potsdamer Platz
News
27 August 2026
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Water Sensitive City

What does a Water Sensitive City look like in practice? Lessons from 9 cities in Europe and beyond

As summer draws to a close, Europe has once again experienced major water-related challenges, with water scarcity, heavy rainfall and localised flooding affecting many regions. How can urban areas cope with these challenges and what does a Water Sensitive City (WSC) actually look like in practice? Two new reports of the WSC Partnerships dive into these questions, exploring several case studies and offering insightful lessons.

The WSC principles are reflected in various urban interventions that can serve as best practice examples for cities across the EU. These include, for instance, public squares that temporarily store stormwater during heavy rainfall (Rotterdam), a network of green roofs, permeable surfaces and rain gardens required through the planning system (Dublin), or a naturalised river corridor integrated into a public park (Singapore). But some of the features that make a city water sensitive are less immediately visible: governance arrangements, financing models, digital platforms, pricing mechanisms and ways of involving citizens.

A new report developed under the Urban Agenda for the EU Water Sensitive City Partnership by EUI expert Ana Contreras Escribano examines good practices from nine cities: Barcelona, Berlin, Dublin, Elche, Rotterdam and Tallinn in Europe, alongside Nanaimo, Singapore and Melbourne as international benchmarks.

The cases were selected to represent different geographical contexts, city sizes and governance structures, and to explore dimensions including infrastructure, citizen science and behavioural change, governance, digitalisation, financing and capacity building.

Water-sensitive infrastructure

Infrastructure is the most widely represented dimension across the nine case studies. The examples range from naturalised waterways and multifunctional public spaces to catchment-scale flood management and digitalised water networks. One common feature is the combination of green and grey infrastructure rather than reliance on either approach alone. The shared lesson across all infrastructure cases is that pilot projects with strong public visibility are the most effective pathway to scaling.

Singapore's ABC (Active, Beautiful, Clean) Waters Programme is the most comprehensive infrastructure reference, delivering 2.7 km of naturalised river corridor at Bishan-AMK Park through bioretention, constructed wetlands, and rain gardens integrated into a public park. The programme applies Sponge City principles at city scale, making ABC features mandatory in all new developments.

Rotterdam's Water Squares are one of the most iconic hybrid infrastructure innovations: multifunctional public spaces storing up to 1,700 m³ of stormwater per square during storm events while functioning as recreational spaces year-round.

Elche's Clot de Galván wetland re-naturalisation, supplied entirely with recycled water, illustrates how 100% wastewater reuse can drive ecological restoration alongside water management.

Berlin's Potsdamer Platz demonstrates the longevity of integrated green-grey systems. Artificial lakes, green roofs, and infiltration systems have operated without flooding for over 20 years, with stormwater reused for tree irrigation during drought.

Melbourne's Elizabeth Street Catchment Study applies a catchment-scale approach combining dual-use water harvesting tanks, permeable surfaces, and green roofs to achieve up to 80% flood depth reductions in central urban areas, demonstrating that addressing flooding at its origin, not only downstream, transforms investment efficiency.

Dublin mandates Nature-based Solutions, including green roofs, permeable surfaces, rain gardens, SUDS, and constructed wetlands, in all new developments through its City Development Plan, making it the strongest regulatory NbS mandate.

How can citizens become part of water-sensitive transformation?

The report also examines how data, citizen participation and incentives can influence the way people interact with urban water systems. Across the cases, however, sustaining citizen involvement remains difficult. Nanaimo, Berlin, Rotterdam and Melbourne all identify maintaining interest over time as an unresolved challenge, suggesting that engagement requires continued programming rather than one-off activities.

Barcelona's ENFORCE project is the most institutionally advanced citizen science case in the group. The Horizon Europe initiative deploys a living lab methodology at urban beaches to engage beachgoers, schools, and universities in monitoring and reducing coastal waste impacting water quality. What distinguishes Barcelona is the institutional infrastructure behind it: a dedicated Citizen Science Office at city level, participation embedded in regulation through Decidim, and citizen-generated data feeding directly into public ordinances.  

Nanaimo demonstrates the most measurable long-term behavioural outcome: a 50% reduction in per-capita consumption over 20 years, achieved primarily through progressive block-rate pricing rather than campaigns. This suggests that financial incentives can be a powerful and sustained mechanism for behaviour change.  

Melbourne highlights the most effective engagement channel: working with existing trusted community groups rather than building new structures from scratch, reaching communities through river festivals already embedded in local identity.  

Rotterdam's co-design model produces a different form of behavioural change: citizens who participate in designing a Water Square treat it as their own infrastructure, maintaining and protecting it over time. The annual storm surge festival is an innovative awareness tool that creates emotional connection to flood risk in high-risk communities.  

Tallinn provides the clearest evidence that data visibility drives behaviour: consumption fell by 6 litres per person per day simply as a result of customers seeing their own real-time usage through SmartFlow dashboards, with no campaign required.  

How do cities finance the transition to water sensitivity?

Cities not only need effective solutions, but also ways to recognise and fund benefits that extend beyond conventional water infrastructure.  Financing is one of the areas where the nine cases differ most from fully self-sustaining tariff models to cities with no structured revenue mechanism for climate adaptation investment.

The analysis reveals the absence of co-benefit quantification frameworks as a key bottleneck. Across the cases, the report identifies the urgent need for a shared methodology for quantifying co-benefits (for monetising ecosystem services, biodiversity gains, heat reduction, and social cohesion), in order to unlock political prioritisation and private investment for water-sensitive infrastructure at scale.

Nanaimo presents the most replicable and self-sustaining financing model: 100% of infrastructure funded through user tariffs, with full-cost accounting, annual recalibration, and a rolling 10-year investment plan. The key innovation is treating investment deferral,  made possible by demand reduction, as a quantified financial efficiency, not merely an environmental outcome.  

Barcelona achieves the best funding diversification in the group, combining municipal budget, national funds, EU Horizon, H2020, and private R&D collaboration, reducing dependency on any single source.  

Berlin orchestrates private investment through planning requirements, making on-site stormwater management a condition of development approval —, delivering infrastructure without public subsidy.  

Dublin uses the same mechanism at city scale: planning conditions and charging mechanisms transform private developers into the primary delivery vehicle for NbS across the full city.  

Elche has accessed NextGen EU funds through the PERTE mechanism, though the heavy bureaucratic burden of EU procurement has been the primary operational challenge — a warning for smaller municipalities across Europe.  

Melbourne faces the most acute financing challenge in the group: climate adaptation for water infrastructure has no direct financial payback within standard investment models, and there are no structured incentives for private investment. The city is actively exploring the insurance sector as a new financing partner with direct financial interest in flood risk reduction outcomes.  

What kind of governance makes a WSC possible?

The nine cases also demonstrate that water-sensitive transformation depends on how responsibilities are organised between institutions. Despite the different governance models, one difficulty appears across all nine cases: cross-departmental coordination, which is consistently cited as the biggest internal governance challenge, regardless of city size, country, or institutional model.

The PUB model, a single national agency with a full water cycle mandate covering supply, drainage, sewerage, and flood resilience,  eliminates the inter-institutional coordination friction that characterises all other cases. While not directly replicable in most European contexts, it provides a clear benchmark for what integrated governance can achieve.  

The city's three-tier coordination model is the most structured multi-level governance reference in the group: a cross-departmental steering group meeting every two months, monthly coordination meetings with two utility providers, and regular structured dialogue with State and national government. This layered, formalised approach is directly transferable to European multi-level governance contexts where fragmentation between local, regional, and national actors remains a persistent gap.  

Berlin and Dublin are the strongest regulatory governance references: both have legally mandated water-sensitive requirements in new developments, backed by dedicated coordination structures. These include the Regenwasseragentur in Berlin and a formal cross- departmental working group in Dublin.  

Barcelona: operates the most developed multi-level network, coordinating simultaneously across metropolitan (AMB), regional (ACA), and European levels, and participating actively in APE, AEOPAS, AMAP, and the Catalan Water Partnership. This demonstrates that network governance across operators and institutions provides resilience in crisis situations, as demonstrated during COVID-19 and the 2022–2025 drought.  

Rotterdam demonstrates the most genuine cross-departmental integration in practice, with Water, Green, Social, and Public Health departments meeting regularly around shared projects and co-designing solutions with communities. 

What role can data and digitalisation play?

The report finds considerable variation in digital maturity, ranging from operational digital twins to cities that are still developing their first integrated platforms. However, across the cases, the report identifies interoperability (connecting legacy systems, sharing information between departments and designing platforms that can serve multiple users) as the common challenge. The lesson is therefore not simply that a WSC needs more data, but that data needs to be connected to governance arrangements capable of using it. 

Barcelona and Singapore are the most advanced, both with operational digital twins, centralised data platforms integrating sensors, satellite, GIS, hydraulic modelling, and early warning systems, and citizen-generated data feeding into governance processes.  

Tallinn leads in a specific and highly transferable niche: network digital management through the SmartFlow platform, integrating SCADA, customer data, acoustic loggers, and the Martinek water loss system into a single environment. The city-wide political mandate for full meter replacement, rather than a pilot approach, is the key innovation, demonstrating that full coverage is achievable and delivers far greater value than incremental deployment.  

Elche is deploying OASIS as its primary digitalisation step, building a centralised platform integrating the full water cycle for the first time, a model relevant to the many European cities still at this transition stage.  

Rotterdam's Open Urban Platform, launched in January 2025, integrates water and socioeconomic data into a city digital twin developed collaboratively with the local university of applied sciences. It provides a model for co-produced urban data infrastructure.  

Berlin's Blue-Green digital planning platform, launching in September 2026, will provide cross-district planning support drawing on the Potsdamer Platz case as its founding reference.  

Melbourne's open data portal and GIS-based catchment modelling represent a targeted, publicly accessible digitalisation approach focused on flood management decision-making rather than full digital twin coverage. The shared gap across all cases is data interoperability. This includes the difficulty of connecting legacy systems, sharing data across departments, and building platforms that serve multiple actors simultaneously. 

Training and capacity building needs for becoming a Water Sensitive City 

Training and capacity building is the thematic area where the gap between need and provision is most acute across the cities. All interviewees identified training as a priority, but structured, sustained training programmes specifically focused on water-sensitive urban design remain rare.  The most cited preferred training formats across all nine cities are case-based learning and peer exchange.

Capacity building needs include cross-departmental water governance, quantifying the wider benefits of nature-based solutions, citizen engagement and co-design, financing, digital integration and catchment-scale planning.

Conclusions of the report

All cities demonstrate measurable results on water consumption, flood risk, and quality outcomes. The diversity of contexts, from Nanaimo's 150,000 inhabitants to Singapore's 5.9 million, confirms that WSC approaches are adaptable across scales.

Where cities have mandated water-sensitive requirements, uptake scaled rapidly. Voluntary approaches alone produce insufficient results. Berlin, Dublin, and Singapore offer three distinct but effective regulatory models.

Progressive tariffs (Nanaimo, Elche) consistently outperform awareness campaigns. Dublin's First Fix Free scheme illustrates that removing financial barriers to engagement can be as effective as incentivising it.

As shown by the case of Melbourne, addressing water challenges at the catchment origin can achieve up to 80% flood depth reductions and radically improves investment efficiency. This principle is directly transferable to European cities.

Cities with centralised platforms need the organisational capacity to act on data. Interoperability and cross-departmental sharing remain critical gaps even in the most advanced cities.

All nine cities identify citizen engagement as a top challenge. Co-design, financial incentives, and education from childhood are the most effective approaches identified. Community group partnerships (Melbourne model) are an underused channel.

EU funds enable pilots, but long-term sustainability requires municipal revenue models and blended finance. Melbourne highlights the insurance sector as an underexplored financing partner.

Melbourne's coordination model (city / state / national) demonstrates that structured, frequent, formalised coordination at multiple levels significantly accelerates implementation

 

How to strengthen citizen participation and drive behaviour change?

A separate Citizen Science Readiness Scan, developed under Action 7 – Community Engagement, looks at how citizen science and behavioural change can support water-sensitive transformation. It maps more than 20 initiatives and combines this with evidence from the nine city case studies.

Its main finding is that participation alone is not enough. The strongest approaches combine meaningful involvement, visible feedback on the results of citizen action, and links to public policy or decision-making. Financial incentives and real-time data also tend to produce more sustained behavioural change than awareness campaigns alone. The report also stresses that cities need the right conditions in place: dedicated staff, reliable data, trusted community partners, long-term funding and mechanisms that connect citizen participation with municipal decisions.

The broader lesson is that a Water Sensitive City is not only one where citizens receive information, but one where they can participate in shaping solutions and see how their actions contribute to tangible outcomes.

Within the framework of the Water Sensitive City Partnership, the Good Practices and Capacity Building Pathways for Water Sensitive Cities and the Citizen Science Readiness Scan reports were developed under Action 6 – Knowledge and Capacity Building, led by LEITAT - Applied Technology Research & Innovation Center (Spain) and Action 7 – Community Engagement, led by the City of Enschede - Gemeente Enschede (the Netherlands)

You can access the full reports and related resources below: