The URWAN Checklist

A dedicated team is needed to manage the complex and multi-dimensional process of planning and designing effective NbS. This team should have a clear leader, a well-defined action plan, and enough funding to do its work properly. In addition, thematic or interdisciplinary working groups should be established to support the main team. By bringing together people with different skills, experience, and knowledge, these groups strengthen the planning process. They help ensure real stakeholder involvement, support co-design activities, address legal and regulatory requirements, confirm technical feasibility, and help build a strong foundation for the long-term management, maintenance and governance of NbS.

Stakeholder involvement is essential for NbS. It ensures that solutions respond to local challenges, needs, and values, while also building public support for their long-term maintenance. When stakeholders are engaged as partners and co-creators, interventions are better adapted to the local context, more widely accepted, properly maintained, and more equitable. Because NbS are often seen as new and complex, their success depends even more on public understanding and acceptance than traditional grey infrastructure. A participatory approach benefits communities by empowering people, strengthening social connections, and fostering a shared sense of responsibility.

It is important to select the most suitable and practical location for the NbS as the site can affect the long-term success of the intervention and determine who and what benefits from it. Poor spatial planning or choosing the wrong site can undermine NbS effectiveness, waste resources, and lead to unintended problems, including environmental injustice (when people are disproportionately impacted by environmental factors because of discrimination).

NbS are only effective, fair, and widely accepted when they are adapted to the specific social, environmental, legal, and institutional conditions of a place. A focused Baseline Assessment helps understand the challenges to be addressed and the local context within which the intervention(s) will be implemented. It helps support informed decisions, align actions with local priorities and strategies, and design strong, evidence-based solutions that work well in that specific location

Co-design supports the development of NbS that people understand, accept, and actively support. It helps identify priority challenges to be addressed and define clear, realistic outcomes from the outset, avoiding misunderstandings and unrealistic expectations. It also ensures that solutions remain flexible and adaptable to evolving urban and climate conditions over time.

A Feasibility Analysis helps check whether an intervention fits the local regulatory, social and environmental conditions. It looks at whether it can be properly maintained over time (including water, staff, community support, and technical skills) and whether it follows existing standards, regulations, and safety rules. Doing a Feasibility Analysis early helps avoid moving forward with solutions where the risks of implementation are greater than the expected benefits.

As ecological, social, and cultural systems are dynamic, a Risk Management Framework offers a clear and structured way to identify, assess, prioritize, monitor, and mitigate risks that could affect the successful implementation of the NbS. It also helps address any expected and unexpected impacts the intervention(s) may create. It looks at how these impacts are shared among different stakeholders and supports early action through corrective measures to reduce harm. Monitoring data also support adaptive management and ongoing improvement of performance over time.

Aligning the NbS with wider policy goals, action plans, and strategies helps strengthen institutional support and improve coordination across different sectors. For effective NbS, it is also important that the intervention(s) build on past or ongoing initiatives and existing infrastructure and look for synergies across different policy and governance levels (local to global) and economic sectors (e.g., tourism, agriculture, etc.).

Successful NbS need clear, open, and inclusive governance that involves different sectors and levels of decision-making, while connecting top-down priorities with bottom-up needs. A participatory governance builds trust and legitimacy, values local knowledge, promotes fair distribution of benefits, and supports long-term success.

NbS are designed to provide wide-ranging social, environmental, and economic benefits. They are expected to provide greater overall value than traditional grey infrastructure. However, municipal finance systems often underestimate their worth because decisions are made in silos and focus mainly on engineered interventions. Accounting for the wide range of NbS co-benefits and avoided harms—such as better public health, flood protection, recreational spaces, and biodiversity—makes a stronger case for including them in urban policies, planning, and investment decisions. Two approaches are usually used:

Cost–benefit analysis (CBA) measures the tangible costs, benefits, avoided damages, and wider co-benefits of NbS. It helps build strong investment cases and calculate cost-benefit ratios.

Cost-effectiveness analysis (CEA) compares the costs of alternative solutions that achieve the same outcome and usually takes long-term performance into account, not just short-term financial returns

The transparent and participatory assessment of how the NbS affect different stakeholders ensures that benefits and costs are fairly shared across stakeholder groups (distributional equity) and that the interventions are equitably placed across neighbourhoods (spatial justice). It prevents reinforcing social inequality or causing green gentrification, while building social trust and acceptance and long-term care of the NbS.

Financial feasibility and long-term sustainability are crucial because NbS take time to deliver real benefits and only provide lasting value if they are properly maintained throughout their life. Focusing only on initial investments, without planning for ongoing costs, maintenance, and eventual handover, can reduce effectiveness, shorten their lifespan, and weaken public trust—especially when benefits take time to appear. Including long-term financial planning from the start builds credibility and public support, even if implementation happens in phases or is delayed. Ensuring durability requires low-maintenance design, clearly defined roles and responsibilities (effective governance), secured multi-year funding, and sustained participatory and community stewardship processes that support NbS as enduring public assets.

Integrating NbS in public budgeting and planning helps ensure they continue beyond individual project cycles. This often means presenting NbS as supporting multiple policy goals, rather than just as separate environmental expenses. Even partial or gradual budget integration can increase institutional ownership and improve chances for long-term maintenance. Tools like fiscal incentives, subsidies, and supportive regulations can help turn pilot NbS projects into permanent budget commitments.