From a theoretical approach based on political ecology and environmental justice, we assess how forestry development has generated socio-spatial dynamics of environmental degradation and water scarcity in southern Chile. Through historical-geographical and ethnographic methods, we discuss how and why the spread of forestry plantations has significantly influenced social and environmental degradation of the Mapuche's modes of living. In response, during recent decades a political articulation of a Mapuche social movement is observed. Their demands include land, autonomy, rights and opportunities to frame their own development strategies. Within the internal diversity of this movement, a key principle is reversing the spread of environmental degradation by recovering the native forest and its natural water cycles, which have been disrupted significantly by the increasing of forestry plantations. We explore these dynamics of the Mapuche movement from an environmental justice approach.