The Indus civilization has challenged scholars’ understanding since its discovery some eighty years ago, and in recent years the application of syste… - Jane McIntosh

[The desertion of the Drishadvati and the Sutlej] is typical of the instability of the river courses in the Indus plains—but in the case of the Saraswati, the effect was not localized but devastating on a major scale. Cities, towns, and villages were abandoned, their inhabitants drifting to other regions of the Indus realms and eastward towards the Ganges, pushing back the centuries-old eastern boundaries of Indus culture and venturing into uncharted territory.

This work revealed an incredibly dense concentration of sites, along the dried-up course of a river that could be identified as the ‘Saraswati’. . . Suddenly it became apparent that the ‘Indus’ Civilization was a misnomer—although the Indus had played a major role in the rise and development of the civilization, the ‘lost Saraswati’ River, judging by the density of settlement along its banks, had contributed an equal or greater part to its prosperity...Many people today refer to this Early state as the ‘Indus-Saraswati Civilization’ and continuing references [in her book] to the ‘Indus Civilization’ should be seen as an abbreviation in which the ‘Saraswati’ is implied.

In the Indus period the Saraswati river system may have been even more productive than that of the Indus, judging by the density of settlement along its course. In the Bahawalpur region, in the western portion of the river, settlement density far exceeded that elsewhere in the Indus civilization . . . While there are some fifty sites known along the Indus, the Saraswati has almost a thousand . . . [The Yamuna] shifted its course eastward early in the second millennium, eventually reaching its current bed by the first millennium, while the Drishadvati bed retained only a small seasonal flow; this seriously decreased the volume of water carried by the Saraswati. The Sutlej gradually shifted its channel northward, eventually being captured by the Indus drainage . . . The loss of the Sutlej waters caused the Saraswati to be reduced to the series of small seasonal rivers familiar today. Surveys show a major reduction in the number and size of settlements in the Saraswati region during the second millennium.