A Landscape Analysis and Pre-Feasibility Study of Urban Nature-Based Solutions to Reduce Flood Risk and Strengthen Resilience in the City of Kigali, Rwanda


WB and the City of Kigali (CoK) collaborate within the RUDP II project to improve urban areas in Kigali including the mitigation of flood effects, upgrading of low income areas, improving environmental conditions and so on. One of the studies carried out under RUDPII was to analyse the potential positive effects of urban nature based solutions in Kigali to mitigate floods, but also to enhance social and environmental conditions. This study was commissioned by the World Bank to a consortium led by Defacto urbanism and included HKV as subconsultant. The study analysed the flood risk in Kigali, developed a long list of nature based solutions (NBS), assessed the NBS in terms of effect on the flood risk, but also the effect on other functions such as social, cultural and environmental. The project also in particular looked at future urban and climate developments and proposed a plan how to address adverse impacts through NBS. A roadmap towards funding of large scale NBS was also provided by the consultant.

HKV provided hydrological expertise, where Job Udo was included as hydrological key expert. HKV applied a distributed hydrological model and hydraulic 1D2D model to assess the current impact of floods, the future impact of floods and the impact with NBS applied. HKV in particular analysed what type of NBS measures are effective under which urban typology. These insights were used to scale up NBS on city wide scale. HKV also developed an unit effect database that enables the client and beneficiaries to assess different sets of measures and their potential effect.

The project results are used to design and implement NBS for a number of areas within Kigali.

It should be noted that the level of detail used and (large) scale applied to model nature based solutions in Kigali is internationally unique.