Absolutely but typically two wells, one to pull water from and one to put the cooled water down. You also need a minimum amount of water flow, depending on the unit and how much heat your home needs.

They're considered better than air-to-air heat pumps which become less efficient as the outside temperature goes down. Ground source units remain efficient in cold weather as the water in the well is below the frost line (only the top few feet of the soil freezes). They cost four or five times more than a typical air-to-air unit though so aren't as common.