Currently, the level of non-revenue water in Iran is 25%, which means that a quarter of the 6 billion cubic meters of water annually supplied to the network is wasted, a water resource management expert said.
“The major part of water loss is in the field of agriculture, which is due to the lack of irrigation and drainage networks. This has caused water to be wasted in various ways and instead of feeding farmlands, it either leaks into the ground or evaporates,” Mohammad Ebrahim Raisi was also quoted as saying by ILNA.
Non-revenue water is water that has been produced and lost before it reaches the destination. Losses can be real losses (through leaks, sometimes also referred to as physical losses) or apparent losses (for example through theft or metering inaccuracies).
Giving an example, Raisi said, “If water is supplied to farmlands through the pipeline, 110 cubic meters of water will be sent to supply 100 cubic meters, but if we transfer water from a concrete canal to supply the same amount of water, 130 cubic meters must be sent because a part of the water evaporates on the way. If it is an earthen canal, 150 cubic meters of water should enter the canal because other than evaporation, a part of water goes into the ground.”
The expert noted that the establishment of modern irrigation and drainage networks can help eliminate part of the water loss in farming and increase irrigation efficiency from 30% to 60%.
The establishment of modern irrigation and drainage networks can help eliminate part of the water loss in farming and increase irrigation efficiency from 30% to 60%
Speaking about the industrial sector, he said this sector has prevented the water loss to some extent by carrying out recycling projects.
“Water loss in the urban sector is high. Money is spent on treating the water that is collected behind the dams and transferring it to the cities. But according to statistics, between 15% and 20% of the water are lost on the way,” he added.
This lost water was called unaccounted-for water in the past, which was the difference between the quantity of water supplied to a city's network and the metered quantity of water used by the customers.
“The name was later changed to non-revenue water. For example, of the total 125 cubic meters of water transferred to a subscriber, about 100 cubic meters reach the destination. This happens while the utility spent money on transferring the whole 125 cubic meters, but the subscriber only pays for 100 cubic meters,” Raisi saidd.
“The most important reason for this loss is that we did not invest enough in the pipelines. Instead of defining new water resources, the authorities should replace worn-out pipes and save water by preventing wastage.”
Although it is impossible to completely prevent water loss, it is feasible to reduce it. There is no such thing as ‘zero wastage’ even in the most developed grids in the world. The average wastage rate in developed countries is 15%.
The goal of reducing water wastage in Iran cannot be accomplished unless 10,000 kilometers of the water grid are rehabilitated.
