Strengthening urban resilience through nature: the potential of ecosystem-based measures for reduction of landslide risk in Rio de Janeiro

Ecosystem-based measures have a high potential to replace or build on engineered solutions for Disaster Risk Reduction (DRR) and Climate Change Adaptation (CCA), not only in rural but also in urban areas. Based on the case study of Rio de Janeiro, Brazil, this working paper reveals the potential for implementing such ecosystem-based measures to protect informal settlements. These so-called favelas are often located on steep slopes and therefore prone to landslides that are triggered by heavy rainfall events. Deforestation and land degradation, inadequate infrastructure and ongoing informal building activities are additionally exacerbating risks.

Different – formal and informal – actors are already involved in urban disaster risk reduction; however, structural measures are mostly limited to engineered approaches and not yet aligned with the urban reforestation program. The two major constraints hindering a more efficient landslide risk management and the inclusion of ecosystem-based approaches that were detected in the study are a lack of coordination among the involved authorities as well as a lack of awareness of the potentials that ecosystem-based approaches offer. Investigations in the favelas Morro da Formiga and Morro dos Prazeres that are in the central and northern zone of Rio de Janeiro and severely affected by land and mudslides in the past, revealed a high potential for ecosystem-based measures for DRR and CCA that has hardly been tapped yet.

Based on literature surveys, expert interviews and site visits, a portfolio of suitable ecosystembased measures for urban DRR and CCA for selected marginal settlements in urban risk areas of Rio de Janeiro is compiled, with lessons for the city and beyond. The potentials detected range from household to urban level, and propose pure ecosystem-based measures, but also hybrid ones and social as well as administrative tools.