“Since the beginning of the current water year [Sept 22, 2020], 379 mcm of water has entered the dams, which is 4% less compared to the 396 mcm in the same period last year,” ILNA quoted Mohammad Shahriari as saying.
“Water inflow in dams has been declining sharply. While 91.9 mcm of water entered the dams from Feb 19 to March 6 last year, the flow has fallen to 51 mcm this year -- down 45%,” he added.
Referring to less rain as the reason for the decrease in dam levels, he said: "Since the beginning of the water year, we have had 191 mm of rainfall in the province, which is 24% less than the same period last year when Tehran registered 252 mm.”
Pointing to the significant decline in rainfall in the 16-day period (Feb 19-March 6) this year compared to a year ago, Shahriari said, "Last year we logged 85 mm of rain in the period while this year it was 5.2 mm. This means more than 90% decrease in rainfall that has impacted the runoff and the amount of water entering the dams resulting in a reduction of 64 mcm of water level in Tehran reservoirs.”
The five dams supplying Tehran include Taleqan, Latyan, Mamlou, Amir Kabir and Lar. Together they can hold 2 billion cubic meters of water.
Giving a breakdown, Shahriari said Taleqan and Mamlou now have 268 mcm and 145 mcm, respectively.
The storage level in Taleqan Dam is now 8 mcm less than last year and in Mamlou, it has declined by 40 mcm.
Amir Kabir Dam holds 101 mcm of water, down 4 mcm compared to last year. Water behind Lar and Latyan is 24 mcm and 28 mcm, respectively. The two dams have registered declines of 4 mcm and 8 mcm compared to a year ago.
Tehran Regional Water Company is struggling to implement water infrastructure projects because of cumbersome regulations and the bloated bureaucracy plus the lack of cooperation from state bodies like the Department of Environment and municipality.
Giving an example, he said the DOE does not allow TRWC increase water transfer from Lar Dam to the east of the capital as the dam is a habitat for red spot trouts, “an issue that can and should be resolved if they (DoE) cooperate”.
Tehran’s population density is 973 per square kilometer, which is 20 times over and above the national average. With nearly 13.5 million people, the capital has 16.5% share of the total population.
Tehran accounts for less than 1.1% of the country’s land area, but is home to 16.5% of the population and 45% of the industrial base.
Shahriari hoped that with better rains in the first two months of spring, the water situation will improve. Potable water consumption in Tehran Province jumped to 626 million cubic meters in the last water year that ended on Sept. 22, 2020. Farmers and industries consumed 14% and 8% more water compared to a year ago.