EghtesadOnline: The National Water and Wastewater Engineering Company of Iran will not allow Tehran Municipality to tap into underground resources in the sprawling capital for watering parks and greenspaces, the head of Tehran Water and Wastewater Company said.
"TM is allowed to use only treated wastewater to irrigate greenspaces," ILNA quoted Mohammad Reza Bakhtiari as saying.
“Tehran Municipality draws 150 million cubic meters of water from depleting underground resources annually. This is while the water crisis has been a serious concern for years. It uses 400,000 cubic meters of water every day, all of which are pumped from underground tables that are in bad shape.”
To help reduce this prohibitive amount, the Energy Ministry and TM signed a contract last September, based on which the latter is obliged to use recycled wastewater instead of the rapidly diminishing underground resources.
As per the contract, TM is required to meet its daily need from unconventional sources, namely treated wastewater.
Bakhtiari noted that TWWC is able to deliver treated wastewater to the capital’s municipality.
“Six wastewater treatment plants are up and running in Tehran, producing 500,000 cubic meters of processed sewage per day,” he said.
“The output, which complies with environmental standards, is piped largely to southern Tehran for farming and industrial use, and is also suitable for greenspaces.”
Recalling that wastewater is playing an increasingly important role in conserving water resources in most countries, he said, “TWWC is ready to supply at least 400,000 cubic meters of wastewater to municipalities” across the megacity that continues to expand despite the mounting urban problems.
Tehran wastewater treatment plants are located in Shahrak-e Gharb, Shahrak-e Mahallati, Ekbatan Town, Zargandeh, Qeytariyeh and Sahebqaraniyeh districts.
An estimated $2 billion have been spent on expanding wastewater infrastructure in the capital that hosts at least 13 million people.
Referring to the rise in water use in Tehran, Bakhtiari said daily consumption has reached 3.7 mcm, up 12% compared to 2019.
Daily water use in the province (240 liters per capita) is 20% higher than in other cities of Iran and 30% above other megacities with the same population.
The amount of potable water used annually in Tehran Province exceeds 1.4 billion cubic meters, accounting for almost 20% of the total freshwater consumption in the country of 80 million plus people.
The five dams supplying water to Tehran (Taleqan, Latyan, Mamlou, Amir Kabir and Lar) hold 790 million cubic meters of water, while the figure was 1.1 billion cubic meters last year.
The unsustainable and dangerous consumption patterns are threatening water supplies in the capital as has been the case in many parts of the country suffering from prolonged drought, falling precipitation and rising temperatures related to global warming.
The sharp decline in groundwater levels is having devastating consequences. Excessive pumping is harming groundwater tables and stopping wells from reaching groundwater. When groundwater is overused, lakes, streams and rivers connected to groundwater also start diminishing.
Overuse of groundwater can also lead to land subsidence, which occurs when there is loss of support below the ground. Destruction of vegetation, increasing possibility of dust storms, holes in the plains and higher salt content in groundwater are other grave consequences of overconsumption.
Energy Ministry data show that the earth is sinking in some plains of Tehran Province by about 0.5 millimeter every day while conditions are more critical in Shahriar and Varamin counties southwest and south of Tehran.