ABSTRACT
The hydrographic history–really the history of the Indus–is extremely complex, and there have been many changes in historic times. The marshy Manchar Lake is alternately drained and fed by the Aral as the Indus is high or low; it is fished in summer by the Mohanas, who in winter grow rabi crops on the dry bed. The Barrage takes advantage of the narrowing and fixing of the Indus by the limestone hills of Sukkur and Rohri. The Indus crossing and nodality ensure considerable commercial activity, and Hyderabad is a growing industrial centre. Agriculture is the mainstay of the Punjab, and before 1947 it was no exaggeration to regard the Indus Plains as the granary of India. The Indus Water Treaty of 1960 gave the waters of the three western rivers to Pakistan, the three eastern to India, which undertook to allow unrestricted flow in the western rivers subject to some carefully specified projects upstream.
