While the capital Tehran’s low rainfall rate has adversely affected its surface and underground water reservoirs, the metropolis’s potable water consumption is about twice the country’s average consumption.
According to ISNA, in spite of the recent rainfall in Tehran, its precipitation rate has fallen by 15% and 34% compared with the long-term average and that of the last water year (ended Sept. 22, 2017) respectively.
The report added that Tehran’s annual potable water demand, met by five dams in the region (22%), surface runoff (20%) and underground water reserves (58%), is estimated at 1.1 billion cubic meters.
The news agency noted that based on the annual statistics, the city’s underground water resources have declined by 150 million cubic meters and the level of Tehran aquifer has fallen by 1.9 meters in the past 11 years.
A significant point is that of the 400 billion cubic meters of water reserves, annually 300 billion cubic meters evaporate, 90 bcm are used in the agriculture sector and less than 10 billion cubic meters are used in the residential sector.
Iran accounts for 1.1% of the world’s total population, but has only 0.32% of global renewable water resources. This is while 85% of the country’s areas are located in arid and semi-arid regions. Nematollah Torki, the head of Tehran's Management and Planning Organization, told ILNA in January that Tehran's water consumption is about 1.5 times over and above the national average.
"Water consumption has increased at an alarming rate not only in the city but also in the province of Tehran. The imprudent use of the dwindling resource will lead to water crises sooner or later," Torki added. The unsustainable and dangerous consumption patterns seriously threaten water supply in the sprawling capital, amid low rainfall and persistent drought.
Some experts and environmentalists denounce a widely-held notion that chronic water shortages can be alleviated only by higher precipitation.
Desertification, climate change, illegal water wells, wasteful farming practices, water-intensive industries in arid regions and injudicious use of water in households are known to have a far greater impact on the worsening crisis.
Tehran Province alone has 13,000 legal and 32,000 illegal water wells.
At present, water inflow into the dams indicates a 33% decline compared to the previous water year, the report said.
