EghtesadOnline: Every year 50 billion cubic meters of water is extracted from groundwater sources in Iran, a water expert said.
Noting that groundwater resources are valuable as reserves formed over long years, Mohammadreza Goldansaz said: "Due to arid and semi-arid climatic conditions in the country, dependence on groundwater a resource is high and rising. As these resources are non-renewable, we will face serious challenges when they are depleted,” ISNA reported.
Almost 60% of water for households and industries and 50% for farming comes from groundwater.”
Surveys of groundwater sources in the plains show that the trend is of the ascending order across the board, Financial Tribune reported.
The steep decline in groundwater levels has 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.
Groundwater overdraft may also lead to land subsidence as it occurs when there is loss of support below the ground.
Destruction of vegetation, increasing the possibility of dust storms, holes in the plains and higher salt content in groundwater are other consequences, the expert noted.
Goldansaz recalled that although all these problems and challenges have been observed in different parts of the country, “groundwater extraction still continues” unabated.
Misconception About Agro Sector
It is usually said that the agriculture sector guzzles over 90% of the water due largely to old, inefficient and unsustainable farming practices.
However, the director general of water and soil department at the Ministry of Agriculture Jihad said last week that the amount of water consumed in farmlands is 65%.
“It seems that there is a misconception about water consumption in the agriculture sector,” Reza Sarafrazi was quoted as saying.
According to the official, very large volumes of water are lost through evaporation in dams. Moreover, seepage in the distribution network (rusting pipelines) is also high and all of these are considered as agricultural consumption.
“One part of the water loss is due to the use in villas to irrigate non-productive trees and fill pools. This too is billed as agro sector use!”
There are over 700,000 known wells across the country, of which 35,000 are illegal. Technological advancement and easy access to digging equipment have further eased the digging of wells.
Sarafrazi says the Energy Ministry has been asked to transform traditional wells into smart wells, but so far only 10% of the wells have undergone the transformation.
‘Smart’ or ‘intelligent’ wells are advanced wells with sensors and valves installed downhole to allow easy and constant monitoring by water authorities.
In the recent past, the Ministry of Agriculture has taken measures to reduce water consumption in fields by equipping farmlands with modern tools.
"Of the 8.5 million hectares of agricultural land in Iran, 2.1 million hectares have been equipped with new irrigation systems that play an indisputable role in reducing water consumption,” Sarafrazi added.
It has been reported that advanced methods have helped improve farming efficiency from 39% to 44%, but this is far below the average global water use efficiency in the key sector -- 75%.
“With the new measures, with one cubic meter of water used in the farms 1.4 kilograms of food is produced. In the past a kilogram of agricultural product needed one cubic meter of water.”
Modern irrigation systems help reduce water loss by allowing farmers to control the flow of water.
Use of drip irrigation that helps reduce water use by up to 40% is being promoted as well. The globally popular system enables farmers and horticulturists to adjust the amount of water they need and avoid waste.
Use of recycled wastewater is an important solution in that it helps farmers meet a notable portion of their water needs for the fields.
Given the large volume of wastewater produced in cities and metropolises, the recycling scheme is expected to make great strides and curb the risky dependence on the fast vanishing groundwater.