The Zamin Dawar area lies between Kajakai Reservoir and Musa Qala Rud (river) in southcentral Afghanistan, about 90 km (kilometers) northeast of Lashkar Gab. The area comprises two main stream drainage areas: that of Gulmesh Mandeh (ephemeral stream) to the east which includes mostly plains with low hills on the east and north slopes and a high limestone scarp on the west slope; and Baghni Rud to the west which drains a mountainous area to the north and spreads onto a large alluvial fan with distributaries leading both to Helmand Rud to the southeast and Musa Qala Rud to the west. Most of the cultivated lands in the Zamin Dawar area lie in the southern part of the Gulmesh plains and in the Baghni alluvial fan, as well as a ribbon of cultivation on the flood plain of Baghni Rud in the mountains. The southern end of the Zamin Dawar area with high terraces and sharply incised ephemeral stream valleys is uninhabited.
Karezes provide the chief source of water in the plains. Some 80 were examined and inventoried during the course of the present investigation. Several springs and one large-yield well also contribute to the water supply on the plains. In Baghni valley, developed springs provide the main source of water supply.
During the present investigation, conducted in 1971,. it was found that the karezes yield a total of about 20,000 ac-ft (acre-feet) (25 million cu m (cubic meters)) of water The springs on the plains yield about 3,000 ac-ft (4 million cu m) per year, and the wells yield about 300 ac-ft (375,000 cu m) per year. The inventoried springs in Baghni valley yield about 6,500 ac-ft (8 million cu m) per year, and probably supply about 70 percent of the total water used in the valley. Therefore,the total amount of water used in the Zamin Dawar area in 1971 was about 32,000 ac-ft (40 million cu m). This amount of water was used to irrigate about i0,000 jiribs (approximately 5,000 acres or 2,000 hectares) of cultivated land and served a population of about 40,000 people.
Twenty years ago the water supply was more than double the 1971 flow from karezes and springs, and the population of the area was probably 60,000 to 70,000 people. During the past 10 years and particularly during the last 3 years, the water table has been declining as a direct result of a dry-weather cycle which has affected much of Afghanistan. Concurrently, the population of the area has declined. Rainfall, based on data from the Kajakai Camp weather station, has declined from a 27-year annual average of about 200 mm (millimeters) to about 160 mm per year, which is the annual average for the last 5 years and equivalent to a reduction of approximately 70,000 ac-ft (88 million cu m) of precipitation per year over the entire area. To compensate for the declining water levels many karezes have been deepened or lengthened at great financial cost to the people.
This report evaluates present ground-water conditions in the area and suggests ways-and means by which more water can be obtained for local requirements.
Additional publication details
USGS Numbered Series
Shallow ground water in the Zamin Dawar area, Helmand Province, Afghanistan
112 p. ill., maps (2 fold. col. in pocket) ; 27 cm.