The second phase of Tabriz Wastewater Treatment Plant is to be completed by the end of the next Iranian year (March 2024).
A total of $10 million are to be spent on the project in East Azarbaijan Province, which will help raise the inflow of treated wastewater to the troubled Urmia Lake by 150%.
The new phase will increase the current water flow to the lake to 4 cubic meters per second, or 125 million cubic meters a year, Mehr News Agency reported.
The second phase of the development project is expected to increase the current capacity of the wastewater treatment plant [130,000 cubic meters per day] to 207,000 cubic meters per day, a large part of which will be diverted to the lake.
Instead of the conventional activated sludge process, the plant is equipped with step-feed aeration system in which primary effluent enters the aeration tank at several points along the length of the tank, rather than at the beginning or head of the tank.
Tabriz is a big city, with a population of 1.6 million, and produces a huge amount of wastewater, the treatment of which could feed the lake despite its long distance from the lake. Close to 70% of Tabriz's urban areas are connected to the wastewater system.
Developing wastewater facilities are in line with the guidelines of Urmia Lake Restoration Project that has tasked towns and cities in the vicinity of Lake Urmia’s catchment area to treat their wastewater and direct it toward the lake.
An estimated 60 million cubic meters of reclaimed wastewater enter Urmia Lake every year, part of which is from treatment plants in Naqadeh, Urmia, Mahabad, Miandoab, Salmas and Boukan in the northwestern province.
Located between the provinces of East and West Azarbaijan, Urmia Lake is a closed water body fed through 21 permanent and 39 seasonal rivers.
It started to desiccate 10 years ago due to a variety of factors, including the construction of a 15-km causeway to shorten travel time between Urmia and Tabriz cities and the construction of several dams that have choked off water supply from the mountains on both sides of the lake.
Other Measures
Despite efforts to transfer treated sewage from Tabriz to the lake, other plans, including the scheme to supply water from Kanisib Dam in Piranshahr, West Azarbaijan Province, to the lake through a tunnel is still lagging.
Deep cracks have appeared on the walls and ceiling of the 40-km tunnel that has been constructed to transfer water from the dam to the lake.
Although the project is complete, it cannot become operational unless the widening cracks are fixed.
The tunnel is part of a plan to restore a lake that has been struggling with serious drought for years, but now the whole scheme is lagging behind as the lake’s situation is worsening.
Once the second-largest saltwater lake in the Middle East, the lake attracted birds and bathers to bask in its turquoise waters. Nonetheless, in the early 1970s, nearly three decades of drought have shriveled the basin, shrinking it by a shocking 90%.
The tunnel, after it is repaired, will allow the transfer of 5 cubic meters of water per second from Kanisib Dam, located near the border with Iraq, to the lake.
With the completion of the project, 600 million cubic meters of water will be transferred to the lake.
Environmental advocates have warned about the deteriorating condition of Urmia Lake, a large salt lake that has shrunk in size because of repeated spells of drought, damming and unrestrained groundwater pumping in surrounding areas. The drying up of Urmia Lake has caused major dust storms in Iran in recent years.
Other measures have been taken to help replenish the lake, including the efficient management of surface and underground water in the lake’s vicinity, sealing over 4,000 illegal wells near the region and promoting sustainable farming on 6,000 hectares.
