[2] Hāmūn is a generic term which refers to shallow lakes (or lagoons), usually seasonal, that occur in the deserts of southeast Iran and adjacent areas of Afghanistan and Pakistan as a product of snowmelt in nearby mountains in spring.

[3] It is located in Afghanistan on the Sīstān marshes west of the Dasht-e Mārgō desert where the Helmand River forms a dendritic delta.

[4][5] It used to cover an area of about 4,000 km2 (1,500 sq mi) with dense reed beds and tamarisk thicket fringing on the edges of the upper lakes.

[4] A trapezoid-shaped basalt outcropping, known as Mount Khajeh,[6] rises up as an island in the middle of which used to be Hāmūn Lake and the northeastern edge of Hāmūn-e Helmand.

Its flat-topped peak rises up 609 meters above sea level with a diameter of 2–2.5 km (1.2–1.6 mi), being the only remaining natural uplift in the Sīstān flatlands.

They fashioned long reed boats to navigate the shallow waters and erected squat, red clay houses to withstand the heat of the desert.

Until the late 20th century, irrigation waxed and waned in the Sīstān Basin for over 4,000 years without destroying the wetlands, but then population rapidly increased and new water management technologies were brought to the region.

[4] Precipitation variability in the Hindu Kush results in alternating periods of flooding in the Helmand and droughts, which may cause entire lagoons to dry up.

Irrigation channels have run dry and agriculture has come to a standstill, which has resulted in the abandonment of many villages as people migrate in search of water.

Most of the crops have been reduced to dust bowl conditions, livestock herds have been decimated, and thriving fishery with an annual catch of around 12,000 tons has been wiped out.