Maybe the city is sinking rather than the sea rising.
My opinion exactly. Water seeks its own level. If the water level has risen one foot in NYC, then it has risen 1 foot everywhere else in the world that has a coastline.
The problem as I see it is that there are too many people in Manhattan. Manhattan is an island and the weight of all these people is causing one end of it to depress; therefore the water level only appears to rise.
If NYC is not careful, the whole of Manhattan will simply tip over.
Similar to Guam!