Hydrogeology is a branch of geology that deals with the study of the distribution, movement, and quality of water in the subsurface. Hydrogeology is concerned with understanding the occurrence, movement, and storage of groundwater in aquifers, which are geological formations that contain water. Hydrogeologists study the properties of rocks and sediments that control the movement of water, the interaction between groundwater and surface water, and the impact of human activities on the quality and quantity of groundwater resources. Hydrogeology is an interdisciplinary field that draws on geology, physics, chemistry, mathematics, and engineering to address a wide range of environmental, geological, and engineering problems.
Hydrogeologists are involved in attempting to solve some of the big questions facing the world today, including sustainable water supply, food and energy production; environmental protection; and coping with climate change. They work closely with a wide range of people, from individual farmers and well owners; to other scientists and engineers; to agronomists, sociologists, economists, policy makers, regulators and planners.