DŌRĪ (Pashto Ḍôrəy; Aslanov, p. 432), river in southern Afghanistan, the main tributary of the Arḡandāb. It originates about 2,500 m above sea level in the Tōba highlands of northern Baluchistan, about 50 km east of the Afghan boundary (for details, see Wylie; summarized in Hughes-Buller, p. 14; Gazetteer of Afghanistan V, pp. 199 ff.) and receives the waters of the Arḡestān (344 km long) and Tarnak (353 km long) rivers on its right bank before its confluence with the Arḡandāb below Qandahār, at an altitude of 890 m. On the left bank it skirts the barren Rēgestān desert. On the upper part of its course it is known as the Kadanay. The total length of the river is 227 km within Afghan territory, where its basin covers 31,955 km2, almost 5 percent of the total area of the country.
The hydrology of the Dōrī is poorly known, as only one water-gauging station has been established on its length, at Taḵt-e Pol (alt. 1,050 m), 99 km above the junction with the Arḡandāb. Furthermore, measurements are available only for the period October 1976 to September 1978. They show a mean discharge of 1.35 m3/sec. At the confluence with the Arḡandāb, however, that would rise to 11 m3/sec, almost twice as much water as is left in the Arḡandāb below the Qandahār oasis (Garbovskiĭ, p. 122).
At Taḵt-e Pol the Dōrī registers extreme seasonal irregularity; the ratio of maximum to minimum mean monthly discharge is above 1,000 (Garbovskiĭ, p. 184 fig. 5.25 ). It is determined entirely by rainfall, which at these latitudes is low and scarce. The seasonal peak flows are recorded in July and August after heavy but short-lived monsoon rains in the Solaymān and Tōba mountains (absolute maximum 154 m3/sec on 21 August 1978, highest mean monthly discharge 7.78 m3/sec in August; Garbovskiĭ, p. 211). Much lower peak flows result from winter cyclonic precipitation (absolute maximum recorded in winter 59.6 m3/sec). In the long periods between successive rain events the flow falls well below 1 m3/sec (lowest mean monthly discharge 0.04 m3/sec in November), and the river may run dry for some time, with only shallow pools in the riverbed.
Although the water of the Dōrī is brackish, it is nevertheless heavily diverted into irrigation channels by means of traditional small earth dams, especially on its upper course (Hughes-Buller; Tate, pp. 240-41). Above Taḵt-e Pol, for example, it has been estimated that 82 percent of the total flow of the river, about 5.80 m3/sec, is diverted for agricultural use (Garbovskiĭ, p. 122). The biannual peak flows permit growing of two crops a year (Gazetteer of Afghanistan V, p. 469; for a list of the major canals between Šāh Pasand and Taḵt-e Pol, see pp. 139-40, 470).
M. G. Aslanov, Afgansko-russkiĭ slovar’ (Afghan-Russian dictionary), Moscow, 1966.
E. A. Garbovskiĭ, Inzhenernaya gidrologiya rek Afganistana (Engineering hydrology of the rivers of Afghanistan), Leningrad, 1989.
R. Hughes-Buller, Quetta-Pishin District, Baluchistan District Gazetteer Series 5, Ajmer, 1907; repr. in Balochistan through the Ages, 2 vols., Quetta, 1979.
Ministry of Water and Power, Hydrological Yearbook 1961-1975, pt. II-4B. Arghandab River Basin, Kabul, 1976.
Idem, Hydrological Yearbook 1976-1978, pt. II. Rivers of Helmand Basin. Ghazni and Helmand, Kabul, 1982.
G. P. Tate, The Frontiers of Baluchistan, Travels on the Borders of Persia and Afghanistan, London, 1909; repr. Lahore, 1976.
H. Wylie, Summary of Report on Toba (1879), India Office Records, London, L/P & S/7/23/1477-82.
Idem, Report on the Toba Plateaux and the Roads Leading Thereto from Pishin and Kadanai, 1879, India Office Records, London, L/P & S/7/23/1482-90.
Originally Published: December 15, 1995
Last Updated: November 29, 2011
This article is available in print.
Vol. VII, Fasc. 5, p. 510-511