When drilling a water borehole, whether you encounter fresh or saltwater depends on various factors, including the geological conditions of the area and the hydrological cycle. Here are some key factors that determine the type of water you may encounter: 1. Aquifer type: The geological composition of the underground rock formations plays a significant role in determining the water quality. Aquifers are underground layers of permeable rock or sediment that can hold and transmit water. Different a