Climate change inherently creates a political stalemate, even as waters begin to creep onto lower Manhattan congress is unable to pass policy. New York City will flood and any effort to prevent this is too little, too late. Only such a catastrophic event could create the will to change the city ata macro scale, so for the second time, in 2050, New York will reconsider its urban strategy.Z_grid first a foremost assumes that the city is too valuable - in building stock investment, history, symbology, and trade relations - to be abandoned outright. The city will remain and we can either better it in the face of adversity or allow it to limp on. The necessary changes cannot be top-down, but they can be shaped by policy. Buildings must remain individual, privately-owned, and disparate and in typical New York fashion will be retrofi t rather than rebuilt. At its most fundamental level, Z_grid consists of a collection of building scale bridges, linking the towers of the city and adding a third dimension to the grid, increasing stability, democracy and unity with in the city.The skyscraper is already an illogical typology, essentially a half mile long cantilever, but when the city is over-run with water, this illogic type becomes impossible. Such isolated structures cannot resist the hydrostatic loads of the ocean currents, they must be reinforced. Relatively few entities own the bulk of the building stock in the city, thus linking towers to each other is both a viable and much more cost effective means of reinforcing the buildings. The resultant a decentralized, rhibsome-like structure that is far more stable, but could be sculpted to create other benefi ts as well.The gird was once considered to be the most democratic urban organization, but in it the public realm is confi ned to a single ground plane, the farther one gets from that plane, the more expensive valuable and private that area becomes. As the city fl oods, that plane extrudesto become a public volume, capable of being accessed equally and unilaterally. No part of a building is more than a few inches of glass away the public realm. Similarly, within the buildings, a multiplicity of public “ground” planes disperse throughout the trucks of the city. Not only is onenever more than ten stories from a public level, movement in the city is faster and easier than ever.With most buildings occupying the area below the ocean waves, no longer is it contradictory for the densest area of the city to be the greenest. The concept of the centralized park is disseminated into a multitude of fractured parks linking rooftops while allowing light to filter down to the city below.Finally, for the first time ever, we see the city united as single metropolis. No one refers to Manhattan, as there is no east river, its beds gradually filled with buildings. Downtown Manhattan and Brooklyn merge into a single entity and other points of high density emerge elsewhere withinthe city.