CBSE Class 10 Answered

The planned drainage system was one of the most distinctive features of the Harappan cities. Historians believe that streets with drains were laid out first and then houses were built along them. Some features of the drainage system:

• Every house was connected to the street drain. House drains emptied themselves into the main drain.  
• The drainage system and drains were covered with bricks or stones. They were provided with inspection holes at regular intervals for cleaning.
• House drains first emptied into sumps into which solid matter settled and wastewater flowed into the street drains.