According to NOAA, sea level rise rates were much higher along the East Coast prior to 1970. In fact, there was no change in sea level along the East Coast from 1970 to 1990.
Tide gauges around the Chesapeake Bay indicate that the relative sea level in the Bay is rising at twice the average global rate of 1.8 mm per year
for now, the net change of sea level in the middle Atlantic area is zero
It is important to remember that tide gauges are primarily a navigation aid. As such, many of these tide gauges are located near ports and other growing population centers. In turn, it is possible that these sites are subject to local land subsidence caused by ground water extraction; an activity known to be increasing around the Chesapeake Bay in recent decades [Gornitz and Seeber, 1990; Holdal and Morrison, 1974]. Changes in the elevation of the land on which the tide gauges rest would also appear as a changes in the relative sea level.
Tide gauges measure sea level changes relative to the land on which the the tide gauge rests. By itself, a tide gauge cannot tell the difference between local crustal motion and sea level changes. The following figures illustrate this point. The dashed red line is at a constant height in all figures. In the first figure, the water level is fixed but the land has fallen.