The transience of populations reflects itself as the life cycle of the buildings. Constantly changing dynamics in the entities of a building also constantly effects the fate of the structure. Even with the proper treatment, the loss of its compatibility in functions with the deterioration of a structure becomes inevitable with the forces of various humanitarian, natural and ecological crises. The examined case that has experienced several phases of ephemerality in its lifetime is the North Brother Island in NYC that people abandoned more than half a century ago. In its many lives, the island has been a quarantine island, the site of one of the deadliest maritime accidents, a last resort housing solution for WWI veterans, and a forced rehabilitation center for young drug addicts. Today the island is occupied with a few abandoned public buildings, which are remnants of its troublesome past, and innumerable plants that have taken over the land after everyone left. And now it is facing its proclaimed sinking that is going to be happening in 100 years. This project is for the treatment of a more than human community in the isolated jungle off the coast of the dense cosmopolitan NYC. In an era defined by the environmental and climatic crises, architecture's long-standing obsession with monumental and immortal buildings has to leave a way for a humbler approach intending to provide habitats for more than one entity in the cycle of life. The design method to answer this problem is to consciously re-creating places on the island by using de-constructed materials from the former buildings of the island with the addition of biodegradable ones. By their dissolving in nature after the sinking, only the skeletons of the structure will remain as a ruin, but also as a new home for underwater life. In conclusion, this approach envisions a safe environment for nature and humans through the different stages of the island until the inevitable yet not to be feared sinking of the island, which will further become the starting point of the new urban infrastructure of underwater life.