Excavated by the Harappa Archaeological Research Project in 1993, this large corbelled drain was built in the middle of an abandoned gateway at Harappa to dispose of rainwater and sewage.
The Great Bath is situated along a north-south street with a drain covered with limestone blocks. In the background is the so-called Granary, while in the foreground are the walls of several domestic structures.
At the southwestern corner of the sloping floor, a small drain first passes through the massive walls of the tank and connects to a corbelled arch drain that curves along the edge of the northern terrace of the granary to the west.
This drain cuts through the edge of the so-called granary. If the entire drain were constructed along with the Great Bath, this feature would indicate that the original "granary" was built before the great bath.
Overview of Harappa Mound AB, Trench 39N, showing the Kot Diji phase levels in the foreground and the Harappa phase levels above, beginning with a baked brick drain (on the far left) and ending with the brick wall that can be seen just behind and
Many large covered drains were constructed with corbelled arches. These drains ran beneath streets and lanes and were large enough for workmen to enter and clear any obstructions.
In some neighborhoods, large courtyards were connected to numerous smaller buildings built at different levels. The pilastered wall on the left supported houses at a higher level.