Water levels were monitored by hydrograph, which in more recent times has changed to a digital monitoring system that tracks the water level, electric conductivity, pH, Eh, and temperature.
Islamic tradition further holds that Hagar and Ishmael found a spring in Mecca, the Zamzam well, from which the Jurhum wanted to drink, and that after their ousting by the Khuza'a tribe, that the Jurhum collected the treasures dedicated to the Kaaba and destroyed the Zamzam well so that nobody would find it.
Many religions also consider particular sources or bodies of water to be sacred or at least auspicious; examples include Lourdes in Roman Catholicism, the Jordan River (at least symbolically) in some Christian churches, the Zamzam Well in Islam and the River Ganges (among many others) in Hinduism.