Assessing Knowledge and Perceptions of Blue–Green Infrastructure among Local Government Officers in the Municipal Corporation of Greater Mumbai

Urban flooding in rapidly urbanizing coastal megacities is increasingly intensified by climate variability, declining permeability, ecological degradation, and infrastructure pressures. In Mumbai, India, flood management continues to rely predominantly on conventional grey stormwater infrastructure despite growing international advocacy for Blue-Green Infrastructure (BGI). However, limited research has examined institutional readiness and governance conditions shaping BGI design, planning and implementation within Indian municipal systems. This study investigates institutional knowledge, perception, and implementation readiness regarding BGI within the Municipal Corporation of Greater Mumbai (MCGM) through a mixed-methods approach combining informal interviews with senior municipal officials and a structured survey administered across the Storm Water Drains (SWD), Planning, and Gardens departments. The findings indicate that Mumbai’s stormwater governance framework remains largely engineering and drainage-capacity oriented, with flooding increasingly recognized as a multi-causal challenge associated with high-intensity rainfall, reduced permeability, drainage limitations, tidal interactions, and rapid urbanization. While institutional responses continue to prioritize grey infrastructure interventions, the interviews and survey findings reveal growing openness toward ecological and hybrid grey–green approaches within future flood-management planning. The survey findings demonstrate widespread institutional awareness regarding flooding occurrence and strong willingness toward BGI implementation across departments. However, technical understanding related to BGI multifunctionality, hydrological performance, implementation mechanisms, and limitations under extreme rainfall conditions remained comparatively uneven across institutional groups. The Planning Department demonstrated comparatively stronger conceptual understanding of BGI and ecological planning approaches, while the SWD and Gardens departments demonstrated comparatively stronger implementation willingness despite lower technical familiarity. The study identifies an important institutional gap between conceptual understanding and implementation readiness within the MCGM and highlights the need for integrated governance, technically grounded hydrological capacity building, and context-specific ecological planning approaches. The findings contribute empirical insights into governance transitions shaping hybrid grey–green stormwater management within dense tropical coastal megacities and support the development of integrated ecological and climate-resilient urban flood-management frameworks.