Cities across sub-Saharan Africa face escalating climate risks — droughts, extreme heat, and frequent floods — that threaten public health, livelihoods and economies. By 2050, the share of urban residents in Africa facing at least eight days a year over 35 degrees C will rise from 66% to 85%, worsening heat-related illnesses and reducing worker productivity. Meanwhile, land-use changes are accelerating biodiversity loss, weakening essential ecosystem services.

With sub-Saharan Africa’s urban population expected to double by 2050, cities must address infrastructure gaps to protect vulnerable communities and ensure a climate-resilient future. This will be especially critical for the 60% of the region’s urban population that live in informal settlements, as they are particularly susceptible to climate risks.

The Green-Gray Infrastructure (GGI) Accelerator works with cities in sub-Saharan Africa to address climate resilience challenges by delivering effective, context-tailored climate and infrastructure solutions. It offers cities technical assistance across the arc of project development — from feasibility to financing, and from pilot implementation to scale and replication. Through the effective scaling of nature-based solutions (NBS) and GGI, these cities will become more livable, equitable, inclusive, resilient, and vibrant.

Green-gray infrastructure leverages the benefits of natural “green” infrastructure like forests and mangroves with traditional “gray” infrastructure like seawalls and water treatment plants. Through this approach, cities can strengthen their existing infrastructure systems while building their climate resilience, protecting biodiversity and enhancing natural ecosystems.

The initial cohort is comprised of 11 cities across seven countries in sub-Saharan Africa: Addis Ababa and Dire Dawa, Ethiopia; Kigali and Musanze, Rwanda; Johannesburg and Gqeberha, South Africa; Bukavu and Uvira, the Democratic Republic of Congo; Nairobi, Kenya; Kumasi, Ghana; and Brazzaville, the Republic of Congo.

The GGI Accelerator builds long-term resilience by providing cities with comprehensive support in five key areas:

  1. Policy Guidance & Institutional Development: We support cities to institutionalize NBS and GGI through equitable strategies and policies, improved regulations, and alignment with climate and water resilience goals. Regionally-tailored research and access to technical experts raise awareness about NBS’ climate and socioeconomic benefits and drive buy-in from governments, donors, and communities.
  2. Project Development & Implementation: We provide guidance on NBS and GGI through strategic risk and opportunity assessments, as well as gender and social equity (GESI)-responsive participatory planning. Cities receive technical assistance on locally appropriate NBS species selection; establishing enabling conditions to advance projects toward feasibility; community and stakeholder outreach; and monitoring, evaluation, and learning (MEL) systems.
  3. Funding, Finance, & Economic Analysis: We connect cities with funders and investors, develop business cases, and support financial structures to facilitate transactions, improve project bankability, and unlock sustainable funding. We also host investor roundtables to develop innovative financial approaches and accelerate investment.
  4. Peer Learning & Capacity Building: We facilitate peer-to-peer learning exchanges where cities share best practices, foster collaboration, and strengthen technical skills for planning, implementation, and maintenance.
  5. Communications & Stakeholder Engagement: We enhance visibility and build momentum for NBS and GGI adoption through outreach to policymakers, communities, and investors, helping cities secure critical buy-in and scale impactful solutions.

The GGI Accelerator is led by WRI Africa, Cities4Forests, and the Urban Water Resilience Initiative, with support from DANIDA, and WRI Ross Center for Sustainable Cities. It aligns with the SUNCASA project, funded by the Government of Canada.

Cover image by Ninara/Flickr