Investing in Africa’s Next Generation of Green-Gray Infrastructure
Oct. 20, 2026 - Around the world, communities are finding out that nature is not a luxury. Wetlands absorb floodwaters, upstream forests reduce flood risks and protect groundwater reserves while parks and tree-lined streets cool down neighborhoods, delivering tangible benefits to communities.
Yet nature-based solutions remain underused. In many places, decision makers rely on gray infrastructure, such as drainage pipes, to solve problems that nature can help address. Even when expertise in green infrastructure exists, financing is often the biggest obstacle. Nature-based solutions have historically been harder to monetize, making it more difficult to attract investments beyond grant funding.
The Ruzizi River Basin, which spans the Democratic Republic of the Congo, Burundi and Rwanda, shows both the challenges and the opportunities. Rain washes sediment from bare, degraded hillsides into Lake Kivu. That sediment reduces the capacity of the Ruzizi I hydropower dam, which supplies electricity to the city of Bukavu and surrounding areas, raising electricity and maintenance costs. Farmers also face reduced yields, threatening their livelihoods.
In response to these challenges, Bukavu’s administration is looking to invest in green infrastructure and nature-based solutions as alternatives to gray infrastructure. But the administration lacks the data needed to measure the potential benefits and develop a viable financing plan.
Many other cities across Africa face the same problem. Addis Ababa, Johannesburg, Nairobi need nature-based solutions to address urban challenges, yet potential investors lack the data to assess whether these projects could generate returns or reduce costs. Avoided costs are a key financial benefit of green infrastructure, but nature-based solutions can also generate revenue. Upstream restoration in the Ruzizi River Basin, for example, could reduce Bukavu's dredging costs by limiting the sediment that heavy rains wash into the reservoir. Restoration could also improve the dam’s performance and increase its capacity to store water, potentially boosting electricity generation and revenue.
Cities have a significant opportunity to scale up nature-based solutions and expand green infrastructure if they can identify their financing needs and determine where private capital could play a viable role.
Some interventions produce widely shared benefits, such as planting trees for cooler neighborhoods and improved air quality. But because these benefits are difficult to monetize directly, such interventions will generally require public budgets, grants or concessional finance. Other interventions can generate dependable revenue streams or contracted payments that attract private investment. In many cases, a blended financing approach combining multiple sources will be the most appropriate solution.
A 2025 report from the World Bank and WRI alongside the African Development Bank has highlighted the need for stronger project preparation, clearer measurement of benefits and stronger connections with funders and financiers.
Several African cities are moving in this direction. Johannesburg and Kigali have policies in place to draw in investments for urban greening and river management. Dire Dawa, an intermediary city, demonstrates that implementing nature-based solutions at scale is possible and can generate meaningful co-benefits, such as green jobs.
Connecting Cities with Partners and Finance
At the Oct. 13-14 Regional Green-Gray Infrastructure Roundtable in Kigali, WRI, alongside the International Institute for Sustainable Development, the World Bank’s Global Facility for Disaster Reduction and Recovery and Rwanda’s Ministry of Infrastructure brought together a cohort of seven cities with a pipeline of green infrastructure concepts. The roundtable connected them with partners and financing to advance their concepts toward implementation. The roundtable was supported by the SUNCASA project, funded by the Government of Canada.
With funders, investors and technical partners in the room, the Regional Green-Gray Infrastructure Roundtable gave cities a focused opportunity to prepare their concepts for investments. Project teams pitched their concepts to receive feedback, learned from peers on how nature-based solutions projects can help respond to different challenges, explored solutions through clinics, improved their concepts through cost benefit analysis and operations and maintenance capacity building sessions, and engaged in structured deal rooms designed to connect projects with sources of expertise and finance.
The Green-Gray Infrastructure Roundtable underscored that financing strategies must evolve beyond individual projects to drive lasting systems change. Such change often starts with a smaller, well-executed concept that demonstrates measurable results and builds confidence among funders, creating opportunities to attract additional co-financing and scale impact over time.
For financiers, the starting point is typically a clear understanding of the project's value including its economic and financial returns, resilience benefits, job creation potential, biodiversity gains and other measurable outcomes. Robust impact assessment and cost-benefit analysis are therefore critical to building a compelling investment case.
Yet raising capital for implementation is only part of the challenge. Lasting success depends on establishing sustainable funding mechanisms for ongoing operations and maintenance to ensure that the benefits of nature-based solutions endure long after the initial investment.
By bringing cities, technical partners and financiers together around these challenges, the Green-Gray Infrastructure Roundtable helped advance a shared goal: building a robust pipeline of promising nature-based solutions concepts ready for investment.
