The PetaJakarta.org project aims at advancing our capacity to understand and promote the resilience of cities to both extreme weather events as a result of climate change and to long-term infrastructure transformation as a process of climate adaptation. PetaJakarta.org is a pioneering web-based platform that harnesses the power of social media by gathering, sorting, and displaying information about flooding for Jakarta residents and governmental agencies in real time. It allows situational information to be collected and disseminated by community members through their location enabled mobile devices, and shared with emergency response agencies. We argue that PetaJakarta.org is, in essence, a self-organizing socio-technical system that couples people, mobile technology and autonomous sensors in a complex network of information. As a consequence, we need to explore the various dimensions of computational justice that characterize this system in order to identify its opportunities and challenges.