Mainstreaming nature-based solutions for climate resilient infrastructure in peri-urban sub-Saharan Africa

Despite a growing recognition of the importance of designing, rehabilitating, and maintaining green infrastructure to provide essential ecosystem services and adapt to climate change, many decision makers in sub-Saharan Africa continue to favour engineered solutions and short term economic growth at the expense of natural landscapes and longer term sustainability agendas. Existing green infrastructure is typically maintained in more affluent suburbs, inadvertently perpetuating historic inequalities. This is in part because there remains a lack of fine-grained, comparative evidence on the barriers and enablers to mainstreaming green infrastructure in peri-urban areas. Here, we developed an analytical framework based on a review of 155 studies, screened to include 29 studies in 24 countries. Results suggest eight overarching categories of interconnected barriers to green infrastructure in peri-urban areas. Using a combinatorial mixed method approach, we then surveyed households in nine settlements in drought-prone Windhoek (n=330) and seven settlements in flood-prone Dar es Salaam (n=502) and conducted key informant interviews (n=118). Peri-urban residents in Windhoek and Dar es Salaam indicated 18 forms of green infrastructure and 47 derived ecosystem services. The most frequently reported barriers were financial (40.8%), legal and institutional barriers (35.8%) followed by land use change and spatial trade-offs (33%) and finally ecosystem disservices (30.6%). The most significant barriers in Dar es Salaam were legal and institutional (22.7%) and in Windhoek were land use change and spatial trade-offs (24.4%). At the household level, the principal barrier was financial; at community and municipal levels the main barriers were related to design, performance, and maintenance; while at the national level, the main barriers were legal and institutional. Embracing institutional cultures of adaptive policymaking, equitable partnerships, co-designing futures, integrated landscape management and experimental innovation have potential to scale long term maintenance for urban green infrastructure and foster agency, creativity and more transformative relationships and outcomes.