The purpose of this study is to imagine how water might transform the city, creating both dwelling space and sublime experience. This project developed from an examination of the variety of important roles played by fountains, both as urban water-supply infrastructures in Baroque Rome, and as works of visual display and pleasure, supporting civic life in urban environments. This thesis proposes new forms in the design of fountains, from small to large-scale architectural and infrastructural interventions, along the High Line in New York City. These designs explore the boundary and environmental conditions by which water shows its various properties according to season, scale, and effect. The designs should engage and impress city-dwellers, not only because of their size, but also due to their exquisite and advanced technology. Once these principles are employed, fountains should create spaces for dreaming, for the creation of memories and for the revitalization of city life.