Rainfall in Catchment Areas Is Down 45%

EghtesadOnline: Precipitation in Iran's six main catchment areas has decreased 45% since the beginning of the current water year that started on Sept. 22.

News ID: ۷۵۱۵۵۳

22 November 2020

The Iran Water Resource Management Company said 23 millimeters of rain (37 billion cubic meters) fell over the last 60 days, down 45% compared to the same period in 2019, the Energy Ministry news portal reported.

Iran is divided into six primary and 31 secondary catchment areas. The six major basins are Central Plateau in Markazi Province, Urmia Lake in the northwest, Persian Gulf and Sea of Oman in the south, Hamoun Wetlands in the east, Karakum basin in the northeast and Caspian Sea in the north.

The Caspian Sea in the north had the highest rainfall at 67 mm so far, yet 33% lower than the year before when 101 mm of rain fell in the picturesque and touristy region.

Although the Persian Gulf and Sea of Oman basin in the south received 51 mm of rainfall in the period (60 days) in 2019, it fell to 27 mm in 2020 down 47%.

Karakum basin in the northeast had 15 mm of rain, down 50% compared to the previous year.

Moreover, close to 13 mm of rainfall was registered in the Central Plateau in Markazi Province less 56% compared to a year ago. The least amount of rain fell in the Hamoun Wetlands in the east reaching 6 mm down 66% compared to 2019.

Conversely, one basin received more rain. Urmia Lake basin in the northwest with 50 mm experienced a 194% rise in the 60 days compared to 2019 when 17 mm of rainfall was registered.

Tehran Deficit

In related news, the website quoted Mohammad Shahriari, a deputy at Tehran Regional Electricity Company, as saying that Tehran’s water deficit is considerable.

Due to low rainfall, Tehran dams now hold 695 million cubic meters of water down 12% or 100 mcm compared to this time last year. Five dams supplying Tehran include Taleqan, Latyan, Mamlou, Karaj and Lar. Together they can hold 2 billion cubic meters of water.

Giving a breakdown, Shahriari noted that Taleqan and Mamlou dams hold 271 mcm and 170 mcm respectively. However, stored water behind Karaj, Lar and Latyan is 120 mcm, 85 mcm and 49 mcm, respectively.

Potable water consumption in Tehran Province jumped to 626 million cubic meters in the last water year that ended on Sept. 22.

Referring to water use in other sectors, the official said farmers and industries in the region consumed 14% and 8% more water compared to a year ago. He did not provide figures.

“Water and wastewater infrastructure in the province, including the ageing infrastructure, which is a major source of seepage, is in dire need of renovation.”

According to Hassan Razavi, managing director of Tehran Regional Water Company, the 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”.

He is of the opinion that “If the water and wastewater infrastructure does not improve, political and social unrest would be inevitable.”

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.