Plains Running Out of Fossil Water

Estimates show Iran holds 500 billion cubic meters of fossil water, of which 300 bcm is fresh water.
Of the total volume of fresh water (300 bcm), close to 170 bcm has been consumed (the rest is depleting rapidly) and normal rainfall will not be able to replenish the diminishing ancient freshwater.
The term fossil water, or paleowater, refers to underground water reservoirs that have been geologically sealed. The water cannot be replenished and may have been locked in for thousands of years. This water is a finite resource and often comes with dangers in addition to the water running out after the population has come to rely upon it.