Issues of disaster and governance in the Brahmaputra Basin of India have been part of different debates within the epistemic boundaries. This study of a social–ecological regime shift, from a prosperous paddy cultivated region within the north bank of the Upper Brahmaputra Valley to a sediment deposited wasteland, unravels the complex relations between narratives of a problem and purposeful action. It is found that policy and practice solutions may not always be grounded in the problem situation but can be shaped by wider discourses and social learning. The study illustrates the continuation of engineering solutions without deeper understanding of their influence on social dynamics, the typification of community behaviour with an ignorance of cultural legacies, and a lack of prioritization of adaptation needs in the novel social–ecological conditions of the region. The conceptual frameworks of flood control debates contribute to distinct discourses influencing policy and praxis, while the discontented riparian community is motivated, by actors influenced by identity and space politics, towards political autonomy. Such influences of opposing discourses may reinforce the narrative of a trust gap between the Indian polity and its Northeast Region. The study further identifies a latent capacity for flexibility in the community, which requires more attention from policy and praxis to explore management solutions in such a complex social–ecological system. The paper argues for science, policy and practice engagements in such contexts and the use of transdisciplinary heuristics for their design to facilitate shared understanding. Copyright © 2017 John Wiley & Sons, Ltd and ERP Environment