Floodplain wetlands are among the most threatened ecosystems in the world. Anthropogenic alteration of river flow regimes has disrupted the inundation cycles that sustain these environments and is leading to serious declines in floodplain wetland condition. Management of inundation regimes using environmental water can regulate the type, quality and quantity of food resources that support diverse communities of wetland biota. We propose a general model of ecosystem productivity which outlines how energy quality and quantity influence ecosystem carrying capacity, and present a novel conceptual model of floodplain wetland energetics which demonstrates how management actions can drive processes to maximise productivity on this basis. The conceptual model describes how short- and long-term hydrologic regimes shape wetland habitat structure, which in turn influences primary production, resource quality, the efficiency of energy transfer among trophic levels, and the connectivity of basal energy resources through wetland food webs during an inundation cycle. We propose that long-term hydrologic maintenance of core wetland habitats will provide detrital-based energy refuges, that when hydrologically connected to intermittently inundated habitats that are fuelled by high quality algal food resources, will substantially improve trophic carrying capacity of wetlands.