Wastewater produced in Behesht Zahra Cemetery where dead bodies including Covid-19 victims are washed does not enter the Tehran sewage collection network, deputy head of the Supervision Department in Tehran Province Water and Wastewater Company said.
“The facility has its own wastewater treatment plant and is equipped with a special grid that is separate from the capital’s sewer network,” Mohammadreza Karami Nezhad was quoted as saying by ISNA.
The plant’s chlorination system is controlled via online tools and TPWWC monitors the wastewater plant on a daily basis, he said.
Under Islamic law, corpses are typically washed with soap and water before burial. Washed and disinfected with sodium hypochlorite, the bodies of those confirmed to have coronavirus at the time of death are sheathed in black bags and their graves are covered with calcium oxide — lime — to prevent contamination of soil and underground water.
“The graveyard’s effluent is recycled in a special facility and transferred to water green spaces in the vicinity (south Tehran).”
Wastewater is managed in compliance with stringent hygiene rules to protect the environment, he noted, adding that unlike other wastewater facilities where chlorine level is 1.2 milligrams per liter, in the huge cemetery’s sewage treatment facility the (chlorine) level is kept at 2.3 milligrams per liter to ensure that pathogens (coronavirus or other viruses) do penetrate and infect underground water resources.
Chlorine, a strong oxidizing and disinfecting agent, is used as the main disinfectant in water treatment.
According to the senior water official, the risk of transmission of viruses including coronavirus through wastewater systems is low due to the fact wastewater treatment plants treat viruses and other pathogens. Viruses are particularly susceptible to disinfection.
The expansion of wastewater networks has been a top priority as it helps prevent pollution of underground water and reduces the need to tap into dwindling underground water tables.
Operating Plants
“Currently six wastewater treatment plants operate in Tehran producing 45,000 cubic meters of sewage a day.”
The output, which complies with environmental norms, goes to south Tehran for farming and is suitable for watering green spaces and industrial use.
Tehran Municipality uses groundwater for green spaces and overuse over decades has resulted in the rapid decline in groundwater levels as large parts of the country grapple with chronic water shortages.
Recalling that wastewater plays an important role in curbing loss of water resources in many countries, he said: “The TPWWC is ready to provide 45,000 cubic meters of wastewater to districts 1, 2, 3, 5 and 6.”
Tehran’s wastewater treatment plants are located in Shahrak-e Gharb, Shahrak-e Mahallati, Ekbatan Town, Zargandeh, Qeytariyeh and Sahebqaraniyeh districts.
An estimated $2 billion has been spent on expanding wastewater infrastructure in the capital that is home to at least 10 million people. Of the 9,000 km wastewater pipelines designed for the capital, close to 7,000 km are in place.
Treatment Capacity
TPWWC reports say 220 wastewater treatment plants are operating in Iran and total sewage treatment capacity has reached 11 million cubic meters a day.
An additional 32 plants are in different stages of construction and are planned to come on stream by 2021.
Over 63,000 km of wastewater pipelines have been laid in the past several years and 295 cities are now connected to the sewage grid.
Approximately 7.5 billion cubic meters of usable water is produced annually, of which 4.3 bcm is wasted. Less than 25% of wastewater is recycled -- a setback that demands proper response and responsibility from those in charge of water affairs.
