I live in sc. our tide change is 7' to 9' where does all that water go and come from?

Answer 1

Due to the gravitational pull of the moon and the sun , the same water on the earth goes up an falls down. due to this , the water from the ocean comes closer to the shore during high tide and goes away from the shore during low tide.
Practically, the water comes from the same ocean itself.

Answer 2

As the earth spins on its axis relative to a nearly fixed moon, the gravitational attraction of the moon draws up a bulge in the ocean waters under the moon. Because the earth spins the bulge moves around the earth causing a high tide under the moon and a low tide elsewhere (except there is a second bulge on the opposite side of the earth because there is less moon gravity there). The bulge is dragged up onto shore and in a bay that narrows the effect can be magnified. The sun's gravitational attraction causes a lesser tide than the moon and the sun and moon either work together or against each other causing the tides to vary in height each cycle of cooperation.

Answer 3

the water remains in the sea, however because of the moon's gravity, it rises at a point in the sea closest to the moon thereby falling at other places and so on.

Answer 4

the ocean