Part 4 - River and the topography of Vārāṇasī

Topography is the most important determining factor of a settlement’s growth. A river often plays a crucial role in forming the topography of a region. Vārāṇasī was located over a high natural levee on the left bank of the Gaṅgā, formed by the deposition of the coarsest elements by the river. Like other large rivers the Gaṅgā too, moving through the alluvial plains in its middle course seldom follows a straight course. Rather it followed a meandering course and thus forming concave and convex bends on the two sides of its flow. Convex side is depositional and concave side is of erosional nature and therefore the convex side is a safe bid for the growth of settlements. But it has been seen that the concave side is a general preference for the growth of settlement. Because despite its gentleness, the convex bank because of its recurrent deposit gradually drifts away from water and eventually cuts off from the water source. Concave bank though having the chances of erosion and flood always touched the water line of the river and hence provided direct access to water. For this reason, ignoring the high risks of flood and destructions settlements grew along the concave bank. It is on the basis of clear understanding of the river channel process and availability of perennial water that on such a high levee on the concave side of the Gaṅgā the city of Vārāṇasī grew.

The river Gaṅgā did not follow the same route from the beginning and changed its course several times. There are many causes to it. Indirect evidences point that once the river Gaṅgā used to flow towards the west than its present course. Because of the enormous load deposited by rivers in this alluvial zone often fill up the river bed and forced the river to change its course. In case of this area from the north heavy Himalayan gravels are deposited here and many small to medium rivers from the Vindhyas unload themselves in the toes on the northern margin of the Vindhyas. The tendency of the Himalayan gravels is to push the river in a southward direction. In case of the Gaṅgā too, it flows to the southernmost extremity, because it cannot be pushed further because the Vindhyas. Due to river piracies many of the rivers in this area either got strengthened or merged to another river, resulting change in the morphology of the area. This can be attested by many dried, abandoned or even cut-off nalas. Because of these restrictions the river had to adjustments. At present the Gaṅgā flows up to the Chunar in an east direction and after its confrontation with the Vindhyas and first takes a north and then a north-eastern direction. This present course is located much east to the earlier channel which is proved by many scars on the land surface.

From the mythical reference of the king Bhagirathi’s penance to bring the Gaṅgā to Vārāṇasī which for a long time was suffering from water crisis, it has been proposed that stupendous human intervention brought back the Gaṅgā to its present position. Probably this was the old course of the river that got buried or abandoned, resulting an aridity of Vārāṇasī. Therefore the human attempt to bring back the river to its original position was made. There are even indications of the river Gomatī extended to touch the Gaṅgā towards the east. The old Vārāṇasī, located on a high levee avoided the threat of flood to a large extent. Luckily presence of a number of local depressions, connected with stream to draw water and outlets to drain excess water and thereby containing enough water for domestic and ritual needs.^[1]