The well of Zamzam near the Ka'ba at the Holy Mosque of Mecca has never dried up and has over the year's always actually fulfilled the demand for water by pilgrims since some centuries ago.
The water of Zamzam has also held the same salt composition and taste ever since it first poured forth. The water has never been chemically treated or chlorinated as is the case with other water pumped into the cities.
According to a report by Al-Khataeb Al-Baghdadi culled by Ghana News Agency in Mecca, biological growth and vegetation usually take place in most wells thus making the water unpalatable and unfit for drinking owing to the growth of algae causing taste and odour problems.
The Zamzam well, however, has not got any sign of biological growth associated with other wells.
On the authority of Muhammed Al- Munkadrr from Jabir, he said that the Prophet Muhammed (peace be upon him) said "Zamzam serves the intention that it was drunk for. I drink it to prevent myself from the thirst on the Day of Judgement" and then he drank the Zamzam water.