Four dams supplying Tehran, namely Taleqan, Latyan, Mamlou and Karaj, are either full or on the verge of overflow, and only one has less water, Seyed Hassan Razavi, managing director of Tehran Regional Water Company said.
Heavy rainfall since the start of the current water year, last September, which reached record levels in the past two months plus melting of snow in the catchment area of the dams, have increased the water in dams to levels unseen in decades, ILNA reported.
Tehran dams together can hold 1.93 billion cubic meters of water. With the recent rains and floodwaters entering the huge structures, there is now 1,000 mcm of water stored in the five dams. This volume is up 34% compared to 660 mcm last year.
Taleqan Dam, 135 kilometers northwest of Tehran, overflowed at the weekend. With the ongoing inflow of water to the reservoir, “it is forecast that the overflow will last for a month,” ILNA quoted Razavi as saying.
With a storage capacity of 420 million cubic meters, Taleqan Dam is one of the five major structures that supplies drinking water to Tehran Province that is home to 13 million people.
With the reservoir full to the brim, its overflow valves were opened at the weekend. A part of the water in the dam is being diverted to farmlands and fields in nearby Qazvin Province.
Located in Qazvin Province, it is a hydroelectric dam with an installed electricity generating capacity of 18 megawatts.
Latyan and Mamlou Almost Full
“Latyan and Mamlou dams are on the verge of overflow,” Razavi said. “Mamlou needs 30 mcm to overflow, which is expected in a week”.
Situated 30 km southeast of Tehran, Mamlou Dam has a capacity of 250 mcm and currently holds 220 mcm of water. It provides south Tehran with potable water and helps meet the need of large farmlands in Varamin and Pakdasht in the vicinity.
“Latyan Dam is 90% full and will be maintained at this level for possible floods in the coming weeks,” the water official was quoted as saying.
Built on Jajrood River, 25 km northeast of Tehran, Latyan Dam can hold 95 mcm of water. It now has 80 mcm. There is a 45 MW hydroelectric power station adjacent the dam.
Karaj Dam Could Overflow
Karaj Dam, built on Karaj River in Alborz Province, 63 km northwest of Tehran, has a capacity of 205 mcm. It now holds 160 mcm.
“It has been intentionally maintained below capacity because of the possibility of flooding. But we expect it to overflow in less than a month,” the official said.
The dam is the main source of drinking water for Tehran. It also supplies to 50,000 hectares of farmland near Karaj, center of Alborz Province. A nearby power plant has a capacity of 90 MW.
The only dam which has little water now is Lar Dam, 70 km northeast of the capital.
Located at the foot of Mount Damavand in Amol County, Mazandaran Province, Lar can keep 960 mcm of water but currently has only 120 mcm water.
Although the water volume is not as significant as the other four dams, it has grown four times compared to a year ago.
“A large amount of snow has covered the catchment area of Lar Dam,” Razavi said. Therefore, when the snow melts in the coming weeks, “we expect to have the highest level of water in the dam since it began operation in 1982”.
Iran suffered from decades of drought and low precipitation and last year was the driest in half a century.
The primary purpose of the dam is to meet Tehran’s needs but prior to the water reaching the city, it is used to power the Kalan and Lavarak hydroelectric power stations, which have a combined installed capacity of 162.5 MW.
