Hybrid infrastructures, hybrid governance: New evidence from Nairobi (Kenya) on green-blue-grey infrastructure in informal settlements

Abstract

In expanding informal neighborhoods of cities in sub-Saharan Africa, sustainable management of storm and wastewater drainage is fundamental to improving living conditions. Planners debate the optimal combination between "green" or natural infrastructure, traditional "grey" infrastructure, and "blue" infrastructure, which mimics natural solutions using artificial materials. Many advocate for small-scale, niche experiments with these approaches in informal settings, in order to learn how to navigate the intrinsic constraints of space, contested land tenure, participation, and local maintenance. This paper reports the benefits and limitations of implementing and managing local green, blue and grey infrastructure solutions in an urban informal setting. We studied ten completed public space projects that featured urban drainage infrastructure in the informal neighborhood of Kibera, Nairobi. The analysis drew from ten surveys with project designers and seven semi-structured interviews with site managers. The studied spaces featured different combinations of green, grey, and blue drainage infrastructure that have evolved over years of operation, maintenance, and change in the settlement. All projects featured participation in design, mixed design methods, hybrid infrastructure, and community governance models with potential to interact successfully with municipal actors. Results show that involvement in the co-development of small-scale green infrastructure changed people's valuation, perception, and stewardship of nature-based systems and ecosystem services. These results have implications for the larger scale adoption, integration, and management of urban drainage infrastructure. They also suggest that hybrid systems of infrastructure and governance constitute a resilient approach to incremental and inclusive upgrading.