This research examines equity and justice impacts of inter-basin water transfers and urban water provision in the Kathmandu Valley of Nepal, providing new insights into how ancient water technologies and contemporary infrastructure projects not only can co-exist, but can also provide additional layers of household water security against the specter of a changing climate. Excavating the deep and hidden histories of the Kathmandu Valley’s native water systems illuminates how development is and can be much broader and more expansive than a mere transition toward industrial modernity, emphasizing instead the multiplicity of pathways that can create the enabling conditions for human societies to lives of meaning and value. Moving from water transfers toward greater water justice, however, will require a more wide-ranging, multi-faceted approach to water provision, one that better links new infrastructure projects with existing dimensions and networks of water use and where a wider range of voices are heard and respected. This research draws on ethnographic interviews, critical social histories and a polymorphous approach toward investigating (geo)political actors to illuminate the challenges of implementing new water mega-projects, while also emphasizing how the existence of multiple modes of water access and diverse forms of governance carries the potential to achieve greater water equity and justice.