Helmand River

Helmand River, river in southwestern Afghanistan and eastern Iran, about 715 miles (1,150 km) long. It is the longest river in Afghanistan and flows through the country’s mountainous heartlands to its arid southwest. It collects water from an area of more than 100,000 square miles (about 260,000 square km), with millions of people reliant on the river for agriculture and drinking water. Known as Haetumant in the Avesta (the sacred book of Zoroastrianism), the river has sustained ancient and medieval cultures in the region for thousands of years.

Course

The Helmand River originates in the Bābā Range of the Hindu Kush mountains in east-central Afghanistan. From its source, it flows southwestward across more than half the length of Afghanistan through a variety of landscapes, from valleys and arid plains to fertile agricultural zones. It passes through several key provinces in Afghanistan, including Orūzgān, Helmand, and Nimruz, before flowing northward for a short distance through Iranian territory and emptying into the Helmand (Sīstān) basin, which is a series of lakes, marshes, and swamps on the Afghan-Iranian border. It receives several tributaries, including the Arghandāb and the Tarnak.

Significance

The Helmand River plays a vital role in sustaining Afghanistan’s agriculture and rural livelihoods, with its basin accounting for about one-third of the country’s irrigated land. For neighboring Iran the Helmand River is not a major national water source. It is, however, the primary lifeline for the country’s Sīstān va Balūchestān province, which receives most of its surface water from the river. The river is also central to Afghanistan’s opium production, particularly in Helmand province, one of the world’s leading poppy-cultivating regions. It also supports biodiversity in the region, particularly the wetlands of the Sīstān basin, which is home to many migratory birds and is a buffer against desertification, the decline of land productivity in dry regions.

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Iran-Afghanistan water dispute

Afghanistan and Iran have been at loggerheads over the waters of the Helmand River since the 1870s, when the British colonial government in Afghanistan demarcated the border. The dispute intensified over the years as floods altered the river’s course, sparking tensions over water access, especially in Iran. The boundary placed most of the river’s upper reaches and major tributaries within Afghan territory, leaving Iran’s Sīstān region, which depended heavily on the river for agriculture and drinking water, downstream and vulnerable to upstream restrictions. This laid the groundwork for a long-standing dispute between the two countries over water rights and access.

Attempts were made in the early 20th century to resolve the dispute, but none succeeded. In 1973 Afghanistan and Iran signed a water-sharing treaty that guaranteed Iran a flow of roughly 780 cubic feet (about 22 cubic meters) per second from the Helmand River. The agreement, however, was never fully implemented largely because of political upheaval in the region, including the 1973 Afghanistan coup, the Iranian Revolution (1978–79), and the 1979 Soviet invasion of Afghanistan. In the following decades conflict, drought, and dam construction in Afghanistan further complicated the dispute. Tensions briefly escalated in May 2023, when Iranian officials accused Afghanistan’s Taliban-led government of obstructing the river’s flow, an allegation that contributed to deadly border clashes between Afghan and Iranian forces.