Kerala is one of India's most vulnerable states in India when it comes to climate-induced disasters. Kerala's public health department grappled with a flood of unprecedented magnitude in August 2018. Situating the flood in the context of Kerala's state and society, this paper addresses three questions: What was the level of flood-prevention preparedness? What were the public health effects and how were they managed? Finally, what policy lessons were learned? Drawing from reports of relevant national and state agencies responsible for disaster management as well as first-hand accounts of nongovernmental organizations and media coverage, this paper argues that while Kerala's flood-prevention preparedness was far from ideal, its postflood response in mounting a rapid and effective rescue and relief operation as well as in preventing a public health crisis was commendable. The paper also shows that impressive achievements in climate-disaster health management can be achieved through a decentralized and participatory public health system in which coordinated public action is managed by a capacious state with the active collaboration of civil society.