The drainage system in Harappan cities is the best example to indicate that how very planned the towns and cities were.

On the study of the drainage system, it has been found that –

• The drainages were laid out before the construction of houses and then the houses were built along with those drains.

• Every house was supposed to have at least one wall along the street which allowed the waste domestic water to flow out into the street drains.

• The lower town planning shows that the roads and streets were laid out in a grid pattern which intersected each other at right angles.

• It also has been found that the human settlement was very much planned and the City was restricted to a fixed Area on the platform.

• Two types of bricks were used in the standard ratio where the length and breadth of the bricks were of four times and twice the height respectively.

• The two types of bricks used were - Sundry bricks and baked bricks.