The separation of drinking water pipes from treated non-potable ones is not economically viable in large cities like Tehran, the head of the state-owned Tehran Province Water and Wastewater Company (Abfa) said.
“Such a project requires laying at least 9,000 kilometers of new pipelines that is neither plausible nor economical,” Mohammad Reza Bakhtiari was also quoted as saying by ISNA.
The official declared that Abfa has no plans to separate drinking water pipes from non-potable ones, adding that reclaiming surface and groundwater resources in the capital city is more viable than establishing a new network to distribute treated and non-treated water.
“Implementing such a project in Tehran requires an investment of $3 billion with no long-term benefits, that is why the implementation of such a plan is out of question,” he said.
Bakhtiari believes that the money can be allocated to more urgent schemes, such as dam building and other supply-oriented initiatives that have been delayed for long.
Tehran Province accounts for 25% of Iran’s total annual water consumption, which is around 100 billion cubic meters.
Despite Bakhtiari’s remarks, of the total annual water consumption in Tehran (250 million cubic meters), less than 20% are used for drinking and the rest is consumed for performing household chores and watering plants.
However, the Abfa chief still insists on supplying more water to residents instead of tapping into unconventional water resources.
Dams supplying water to Tehran include Taleqan, Latyan, Mamlou, Karaj and Lar. The five dams together can hold 2 billion cubic meters of water, but the water stored in them is now less than 12% of their total capacity.
Almost 30% of potable water demand in the province can be met through dams and the rest must be extracted from underground resources, which are already in a bad state.
A survey of water consumption trend in the first half of the current Iranian year in Tehran Province (March 21-Sept. 22) shows that only 37% of households had normal consumption and other consumers were in the "high consumption" and "bad consumption" categories.
According to these statistics, 59% of the subscribers are heavy consumers, using 14 to 28 cubic meters per month, which is twice the defined consumption pattern, and 4% of the subscribers are considered high consumers as their consumption has exceeded 28 cubic meters per month.
According to reports, this category of subscribers alone consumes 10% of the total domestic drinking water in Tehran.
Consumption Pattern
Unsustainable consumption pattern seriously threatens water supply in the sprawling capital amid low rainfall and persistent drought.
Pointing to Tehran's water supply plight, Bakhtiari said most people realize the severity of the problem, so they must consume water more responsibly, such that the daily water consumption of Tehran’s residents should not surpass 250 liters.
“State and private organizations should also be compelled to use water more judiciously to help mitigate the impact of the unprecedented water shortage in Tehran,” he added.
In order to protect water resources, which have been decreasing due to the continued drought in recent years, the water supply of high consumers is cut off during certain hours of the day. This measure will continue until they reduce their consumption and follow the pattern.
Reports say close to 500,000 heavy consumers have been notified by Tehran Regional Water Company to reduce their consumption level by at least 25%, otherwise their water supply will be cut off.
Desertification, climate change, illegal water wells, wasteful farming practices, water-intensive industries in arid regions and injudicious water use in households are known to have a far greater impact on the worsening crisis.
Reportedly, there are 13,000 legal and 32,000 illegal water wells in Tehran Province alone.
“Injudicious consumption across Tehran Province over the past 15 years has taken a toll on water resources to such an extent that we’re using 150 million cubic meters of renewable water more than we should,” the official said.
Referring to programs to help reduce consumption, Bakhtiari said households should be encouraged to use domestic water-saving accessories (ranging from shower heads to taps, flush reducers to bathwater diverters) as it can cut consumption by 30%.
Heavily Subsidized
Water is heavily subsidized in Iran. While urban consumers pay 43% of its real price, only 23% of the production costs are paid by rural residents.
The production of 1 cubic meter of water for urban use costs 4 cents while supplying the same to rural areas costs higher.
Non-potable water sources include rainwater, reclaimed/recycled water and grey water. While non-potable water is not suitable for human consumption, it can be used for a myriad of other applications, such as toilet flushing and cooling tower of power plants.
Water supplies are finite while future demand on that water is infinite.
As populations continue to grow we can’t keep using precious, treated drinking water to flush toilets and urinals, to irrigate landscapes or for other huge water consumers like cooling tower make-up that can easily use “less than potable” water.
It has been said that in future decades, the supply of clean fresh water will be far more important to the people of the earth than the supply of oil could ever be.
