Purity: Ruling on Non-Flowing Spring Water Replenished Upon Use
Practical Laws of Islam as per the teachings of Ayatullah Sistani
Ruling 29
The water of a spring that is not flowing but is such that if water is taken from it water gushes out again is not ruled to be flowing water, meaning that if an impurity comes into contact with it and the water is less than kurr, it becomes impure.
-Ayatullah Sistani, Practical Laws of Islam, Purification (Taharah)