Ain ez Zarqa explained

Ain ez Zarqa (also spelled Ayn ez Zarqa or Ain-el-Zerqa) is a natural artesian karst spring located south of Hermel in the Beqaa Governorate, in central Lebanon.^[1] Producing an average of 3,435 gallons per second, it is the main source of the Orontes River.^{[2] [3]} Because of its heavy flow, it is characterized as a first-magnitude spring.^[4] It sits beneath the caves at Deir Mar Maroun, an ancient monastery carved into the cliffs that surround the spring.^[5] Melting snow from these nearby heights supplements the spring's large groundwater reservoir, in the Jurassic and Cretaceous strata. It is estimated that the spring's phreatic zone reservoir contains as much as 10 billion cubic metres of storage. As a result, its flow has been less affected by overpumping and drought than other springs in the Orontes river basin.^[6]

References

1. Book: Lebanon. 1 March 2012. Bradt Travel Guides. 978-1-84162-370-2. 215–. Paul Doyle. 15 October 2012.
2. Book: Natural Wonders of the World. Reader's Digest Association, Inc. 1980. 0-89577-087-3. Scheffel. Richard L.. United States of America. 34. Wernet. Susan J..
3. Book: The Oxford Handbook of the Archaeology of the Levant: c. 8000-332 BCE. Steiner. Margreet L.. Killebrew. Ann E.. 2014-01-16. OUP Oxford. 9780191662546. 376. en.
4. Edgell. H. S.. 1997-09-01. Karst and hydrogeology of Lebanon. Carbonates and Evaporites. en. 12. 2. 220–235. 10.1007/BF03175419. 130137144. 1878-5212.
5. Book: History of Baalbek. Book Tree. 1999. 978-1-58509-063-1. 49–. Michel M. Alouf. Tedd St Rain. 15 October 2012.
6. Book: Karst without Boundaries. Stevanović. Zoran. Krešić. Neven. Kukurić. Neno. 2016-04-14. CRC Press. 9781498787734. 54–57. en.