Water in dams surrounding the capital in the last water year (Sept. 23, 2017-Sept. 22, 2018) has declined by 210 million cubic meters -- a 25% decrease compared to the corresponding period last year.
The Energy Ministry said precipitation in Tehran Province reached 256 millimeters in the 12-month period, showing a decrease of 21% compared to the year before, Mehr News Agency reported.
The decline in rainfall has caused the amount of water inflow into the five dams of the province namely Karaj, Latyan, Taleqan, Lar and Mamlou to fall by a massive 32% compared to the previous year.
Tehran experienced an unprecedented decline in rainfall last fall and winter that caused the total volume of water entering into the five dams to fall to 1.16 billion cubic meters, almost 560 mcm less than the figure in the year before, which stood at 1.72 bcm.
Furthermore, the current volume of water in the five dams amounts to 642 mcm, suggesting a 25% decline from the corresponding period last year.
Among the five dams in the province, Karaj Dam is currently 79% full. It has 144 mcm of water, 6% less than the volume the year before.
Lar Dam is suffering from a 61% decline in water storage compared to the last year. Now it stores 43 mcm of water, 68 mcm less than the previous year.
It can hold 960 mcm of water but currently, 95% capacity of the dam is empty. Located 70km northeast of the capital, the dam is used to supply drinking water and provide irrigation water to Tehran.
Hormozgan Surface Runoff
In the past 17 years, average rainfall in Hormozgan Province has declined from 185 mm to 136 mm and as a result, the province surface runoff has decreased from 13 bcm to 9 bcm, indicating a 30% decline, said the managing director of the Regional Water Company in the southern province.
Houshang Molaei said Hormozgan has had two successive decades of drought in the last 50 years and is now one of the most-parched provinces.
"Increase in the number of wells in the province to more than 25,000 in recent years has created a situation wherein harvesting of water resources now surpasses 1.5 bcm while the surface runoff this year is 400 to 500 mcm.”
Illegal wells estimated at 170,000 have become a major problem for the water authorities trying (apparently without success) to curb the high extraction and consumption rates, namely in the key agricultural regions.
Iran is facing the worst drought in half a century and large parts of the country will soon face severe water deficits as the water crisis worsens and no solution is in place.
Expansion of industries, population growth, mismanagement, waste…have far outpaced the amont of rainfall and the development of water technologies, leading to desiccation of wetlands and rivers.
In addition, per capita water use in metropolises such as Tehran exceeds 200 liters, whereas the global average is close to 150 liters.
Independent experts, environmentalists and academia insist that it is not only high agricultural consumption that has created the wholesale water crisis. Mismanagement of water resources, including multiple damming projects on major rivers, both in Iran and the neighboring countries, have made a bad situation worse by altering the natural water flow.
