Multi-stakeholder collaboration in improving city resilience: A case study of Malang City's adaptation to flood risk

Enhancing Malang City’s flood disaster resilience is critical due to significant environmental degradation. Frequent flooding in the Klojen, Kedungkandang, and Lowokwaru Sub-districts, is driven by land-use changes, massive development, and urbanization, which limit water infiltration. This study analyzes how multiple agencies collaborate to improve resilience, using a qualitative case study approach to gather specific, in-depth information, with thematic analysis used to map the data alignment. The study structured the collaboration context and identified the distinct roles of key agencies. The DPUPRPKP (Department of Public Works, Spatial Planning, Housing, and Settlement Areas) is responsible for drainage; it conducts regular evaluation and maintenance of the city's drainage system to advance flood prevention. BPBD (Regional Disaster Management Agency) acts by installing 24 Early Warning Systems at flood-prone sites to alert and prepare the community. The DPUPRPKP uses a channel return period—academic and BPBD-derived metrics guiding infrastructure capacity—while BPBD relies on regional and city vulnerability maps to assess risk and guide response. Regarding spatial and temporal interventions, DPUPRPKP implements sudetan (artificial diversion channels) at targeted inundation points to reduce immediate risk, while BPBD utilizes the Brantas River flow strategy for long-term mitigation and maintains short-term coordination with the Brantas River Basin Authority (BBWS) to ensure response readiness.