Water that is provided by a spring is accessible either before or after it reaches the ground’s surface. When spring water is exposed it is a form of surface water and when not exposed, it is a form of ground water. Where it is accessed dictates how the water should be treated.
A properly constructed spring source can provide the best of both worlds: the protection of ground water and the easy access of surface water. Often springs have not been developed properly and are just open surface water; these types of springs are very susceptible to contamination. If possible, a spring should be developed in the same way you would develop a shallow well.