If water in a watershed moved from an ocean what would happen to the ground water?

Answer 1

I am not sure I understand your question.

If you mean what is the water cycle? The oceans evaporate, clouds carry the water over land, it rains, the water flows back to the ocean.

If you mean what happens to an area that is flooded by ocean water? The salt in the water would likely destroy the crops but it may or may not affect the drinkability of the ground water depending on the geology of the area. If the source of the local groundwater is above the flooded area the source water could still be untainted.

Answer 2

I'm not sure what you mean, so I will answer in two ways:

If water moves from the ocean onto the land (as in the case of higher ocean levels from global warming), then the water seeping through the soil into the groundwater may contaminate the aquifer with salts.

I suspect you mean this, though ....

If the water all runs off to the ocean, then the ground water would not be replenished. The amount of water in the aquifer would be reduced.