What’s behind the Afghanistan-Iran border clashes?

A tense calm has now settled along the Afghanistan-Iran border after their security forces exchanged heavy gunfire on May 27 over what appears to be a lingering water dispute.

Three soldiers, two Iranian and one Afghan, were killed in the weekend clash, which stems from the question of how to share the Helmand River, which flows from Afghanistan into Iran.

Iran’s eastern region is facing a drought, and Tehran blames the Kabul administration for curtailing water flow.

This is one of the most serious challenges the two sides are facing since the Taliban took control of Kabul in 2021.

What’s behind the latest dispute

Earlier in May, Iran’s President Ebrahim Raisi kicked off a war of words when he warned Afghan officials against violating Iran’s water rights over the 1100-km-long Helmand River, a transborder source of water.

“We will not allow the rights of our people to be violated,” Raisi said.

In an immediate reaction, Zabiullah Mujahid, a spokesman for the Islamic Emirate of Afghanistan, said that using harsh statements won’t help solve the water crisis.

Kabul is abiding by the 1973 water treaty on water sharing, and the cause of the shortage stems from the low water level in the upstream tributary of Helmand River, he said.

Iran wants to send a panel of experts to a reservoir built on the river in Afghanistan to ascertain if the water level has indeed dropped.

Why is the river so important?

The Helmand River is endorheic, meaning at the tail end, its water accumulates in a lake and doesn’t drop into the sea.

Helmand’s journey begins in the Hindu Kush mountain range as it gathers water from the melting snow and then flows down, collecting rainwater, its basin extending over more than one-third of Afghanistan’s landmass.

For Afghanistan, the river is indispensable as it is a source of drinking water and helps irrigate farmland via a network of canals and waterways.

Afghanistan has long faced the stigma of being the world’s largest producer of opium, a byproduct of the poppy plant. Poppy plant doesn’t require much water and can be grown in abundance in Afghanistan. If Afghan farmers don’t get enough water for other crops, they might resort to poppy cultivation.

Farmers in Iran’s Sistan-Baluchestan province, a dry region, which receives little rainfall, also rely on Helmand to cultivate their crops -- the main source of income in the region.

Politically speaking, Iran, which is ruled by a Shia Muslim clergy, has even more at stake than Afghanistan.

The restive Sistan-Baluchestan is home to Sunni Muslims who often complain of facing discrimination from Tehran. In late 2022, the province saw violent protests after a senior police officer allegedly assaulted a teenage girl.

What has led to the shortage?

Water from the Helmand River is shared under the 1973 water treaty between Afghanistan and Iran. Under the terms of the deal, Iran is supposed to receive 22 cubic metres per second of water. Tehran can buy an additional four cubic metres per second of water flow depending on availability.

Kabul says Iran is drawing more than its share of water.

The two sides have periodically argued over the water-sharing mechanism, especially during drought like the long spell witnessed in the early 2000s.

“Both countries have continued to build dams and dig wells without environmental surveys, diverted the flow of water, and planted crops not suitable for the changing climate,” Fatemeh Aman, an analyst, wrote in a paper for the Atlantic Council.

Despite Iranian opposition, Afghanistan has built dams over the Helmand River, including the Arghandab and Kajaki dams. Former Afghan President Ashraf Ghani inaugurated the Kamal Khan Dam built on Helmand in the Nimruz province, which borders Sistan-Baluchestan.

Besides irrigation, Afghanistan wants to build dams like Kamal Khan to meet its electricity needs because it depends on imports to light up homes and power factories.