In our cities, the urban poor—those least responsible for greenhouse gas emissions—bear the brunt of climate change and other urban crises.

 Over 1 billion people live in informal settlements, a number projected to triple by 2050. These communities are at risk due to their locations in environmentally degraded or hazard-prone areas, overcrowded living conditions and limited access to basic services and infrastructure. Most residents work in the informal economy, lacking financial buffers and social safety nets, making it hard to adapt to changing climates.

Despite these risks, climate adaptation planning often follows a top-down approach, driven at national or sub-national levels. This approach relies on climate models that present averages which can obscure the local nuances and uncertainties of climate impacts. There’s limited focus on engaging with or collecting disaggregated data about informal settlements, where the risks are highest. As a result, adaptation investments are poorly targeted, missing key insights and opportunities to minimize the impacts of extreme weather, protect vulnerable groups, reduce poverty, and preserve ecosystems.

For real, lasting change and avoid maladaptation, we need to complement top-down with  bottom-up approach to climate adaptation—one that includes and empowers the communities most at risk as equal partners. Here’s why:

• Information matters. Understanding who lives in these settlements, what they need, and what risks they face is essential to crafting solutions that work.
• Communities are part of the solution. In many rapidly growing cities, majority of the population live in informal settlements (e.g., Nairobi, Kampala). Recognizing and involving these communities can lead to innovative, locally tailored solutions.
• We need scale. Top-down planning alone can’t deliver the locally-led adaptation we need. But when it's complemented with grassroots action, we get a more integrated and effective approach.
• Maximize financing. Residents of informal settlements spend a substantial amount of their income coping with and recovering from climate conditions. That’s a huge financial strain for communities already struggling with daily needs —and a missed opportunity to direct that spending toward more long-term adaptation.
• Promote shared ownership. When communities are involved in shaping solutions, they’re more invested in seeing results. Local-level decision-making and collaboration structures can drive inclusive cities.

Importantly, people in informal settlements aren’t just waiting for help. They’re already responding to climate challenges in the best ways they can.  Take Kombo and Kwa Pakacha settlements in Dar es Salaam, for example. Here, residents can spend up to one third of their income coping with the impacts of climate conditions. At the household level, people try to balance the costs of climate shocks alongside meeting the costs of everyday life. At the community level, organized savings groups and networks can help improve housing and reduce climate exposure. While individual and community efforts help, long-term adaptation requires complementary government investment in infrastructure, service improvements and tenure security.

Photo credit: Centre for Community Initiatives, CCI Tanzania

So, how do we bridge the gap between local action and big-picture planning?

One promising approach is Results-Based Finance (RBF). A World Bank report on “Community-led Climate Adaptation in Informal Settlements”—authored with the International Institute for Environment and Development (IIED) and the Centre for Community Initiatives (CCI) Tanzania—explores how RBF can enhance program impact and overcome key challenges in supporting community-led adaptation:

• Improve targeting and incentivize institutional change. RBF can better target underserved areas and residents of informal settlements. It can also build government capacity and support new partnerships with community-based organizations.
• Filling data gaps. Many informal settlements don’t show up in official records. RBF can support community-led data collection, providing a clearer picture of who’s at risk and what’s needed for evidence-based climate adaptation planning.
• Piloting new solutions. RBF rewards outcomes, allowing delivery partners to pilot new approaches, measure what works, and scale up workable solutions.
• Leverage public and private finance. RBF can reduce investment risks, making it easier to mobilize investment for community-led adaptation. It can remove cost barriers that limit extending public services into informal settlements and incentivize household and community-level collective investment in small-scale adaptation measures.

The scale and complexity of climate adaptation with rapid urbanization and escalating risks cannot be overstated. By connecting strategic investment in infrastructure, driven by national and city governments, with mobilized grassroots action, we can achieve more cost-effective and impactful urban climate adaptation. Inclusive approaches, such as community-led data collection and the co-design of locally led climate adaptation solutions with organized communities, are essential. When combined with innovative climate financing like RBF, these approaches can bridge the climate financing gap for the most vulnerable areas, strengthen institutions, and foster new patterns of collaborative working.

Related

• Report: Community-Led Climate Adaptation in Informal Settlements
• Urban Development at the World Bank
• International Institute for Environment and Development (IIED)
• Centre for Community Initiatives (CCI) Tanzania