Abstract: The complexity of water management requires an explanatory framework that is able to capture the multidimensionality of the relations between nature and society increasingly mediated by the state. The evolution of water problems in the Baixada Fluminense, a wetland
area situated to the north of Rio de Janeiro, provides a paradigmatic example of how water management becomes incorporated into the fluid politics between state, nature and society. The local experience is examined by making use of the strategic‐relational approach (after Bob Jessop)
expanded to urban political ecology. The concept of “trialectics” is proposed as an ontological representation of the interconnections between the state apparatus, class‐based relations and the socionatural elements of the water cycle. The empirical results show that, in
a situation of precarious water supply, regular flooding and severe river degradation, state interventions have tended to favour certain groups and areas, which only intensifies the politicisation of water management.