“The overall plan is for constructing 9,000 kilometers of wastewater network of which 6,800 km are in place,” Mohammadreza Bakhtiari was quoted as saying by Mehr News Agency.
Pipe laying work has been undertaken in all 22 districts of the expanding capital to connect households and industries to the wastewater network.
Tehran Province has 15 wastewater treatment plants, seven of which are within Tehran City, according to Financial Tribune.
“The plants in the province are planned to produce 850 million cubic meters of water per annum by 2030,” Bakhtiari said.
With modern technology it is possible to reuse sewage effluent for drinking water needs, although this is usually only done in places with limited water supplies, such as Singapore.
However, in arid countries, like Iran, wastewater treatment plants provide water for farming and industrial needs.
Sewage treatment is the process of removing contaminants from municipal wastewater, containing mainly household sewage plus some industrial wastewater.
Physical, chemical and biological processes are used to remove contaminants and produce treated wastewater that is safe enough for release into the environment.
Expediting construction of wastewater treatment plants in Tehran is a priority of the TPWWC.
Construction Work Slow
Despite gradual expansion of the network, construction of plants has fallen behind. “So far only 45% progress has been made. Over the past two years, the focus is more on completing the sewage plants,” the official added.
Construction of Firooz Bahram Wastewater Treatment Plant on the western flank of the capital is underway. “It will cost $156 million and is expected to come into operation next year,” he said.
Expansion of sewerages helps prevent pollution of underground water resources and cuts the need to tap into dwindling underground water tables.
An estimated $2 billion has been spent on Tehran’s wastewater network since 1995. Completing the network and building treatment plants requires another $1.6 billion.
Tehran’s water reserves are estimated at 1.06 billion cubic meters, 70% of which comes from surface waters and 30% is groundwater.
National Status
Official reports say 220 wastewater treatment plants are operating and total sewage treatment capacity has reached 11 million cubic meters a day.
An additional 32 plants are in different stages of construction and will come on stream by 2021.
Over 63,000 km of wastewater networks have been laid and 295 cities are now connected to the national grid.
Approximately 7.5 billion cubic meters of usable water are produced annually, of which 4.3 bcm is wasted. Less than 25% of wastewater is recycled -- a setback that demands responsibility and response from those in charge of water affairs.
With help from knowledge-based companies and domestic manufactures, a part of the equipment for the wastewater treatment plants has been indigenized. But it is apparent that much more needs to be done.