"An estimated 278 million cubic meters of water was used in the period in the capital. The figure was 267 mcm last year," Mohammadreza Bakhtiari was quoted as saying by ILNA.
Soaring temperatures during the past two weeks (35°C and above) has made households and businesses crank up cooling systems that are very water-intensive. Majority of homes use the traditional water coolers.
The weatherman has forecast Tehran's temperature to reach over 40 degrees Celsius in the next few days, Financial Tribune reported.
"Close to 3 mcm of water is used in Tehran on a daily basis," Bakhtiari said.
Referring to global standards, he said a 4-member family's average water use is 15 cubic meters per month in the world, whereas in Tehran it is 30 cubic meters for almost 40% of households.
Bakhtiari went on to say that high consumers fill their swimming pools with potable water and are regularly warned to refrain from such practices.
"When necessary, water will be cut," Bakhtiari warned. Energy experts including Qasem Taqizadeh Khamesi, a deputy manager at the National Water and Wastewater Engineering Company, say cutting water supply should be the “last option” and only when all other alternatives have failed.
According to Khamesi, 7.3 bcm of water is extracted from 303,000 illegal wells nationwide and sealing them can produce better and sustainable results.
Users pay 10,700 rials (10.7 cents) for one cubic meter of water, Bakhtiari said.
One main culprit that results in wasteful water practices, the official stressed, is the low price for both farming and drinking.
“Urban and rural consumers of potable water, for example, pay only 47% and 27% of the cost price of water respectively.”
Granting subsidies to agriculture, including for water, he said, is a norm in many parts of the world, but paying attention to how and to what extent this is viable from an economic point of view is very important.
Referring to water shortage, he noted that despite the heavy rainfall in April and May, water deficit in water reserves is close to 130 billion cubic meters.
"Not all rainwater can be stored because 20% of the capacity of dams should be empty to help control possible floods," he said.
Bakhtiari said even if dams are full, the infrastructure to supply water must be rehabilitated and developed.