This is a study of the social and ecological transitions around erstwhile agriculture-centered water bodies at the periphery of a rapidly expanding city. It critically engages with the concept of horizontal and vertical (scale) conflicts through an empirical study of the various processes and challenges faced by different users in the context of the Ossudu tank/lake, a water body near Puducherry city in South India. The study finds that in the transition to the urban sphere, local use for recreation rises in importance, while environmental concerns and real estate demands form opposing pressures on the lake area. Issues of power, marginality, and justice mirror and strengthen each other both on the horizontal and vertical axes, determining the future of the lake. It is argued that the neoliberal recreation paradigm leaves out the urban working class, while at the same time being a part of shifts in natural resource management that disempower and alienate dalits, landless, and nomadic communities. The study highlights the need to bring users rather than uses to the forefront of rediscovering the continuing purposes of these water systems.