what important role did the Indus River play in the development of the Harappan civilization?

Indus valley civilization or the Harappan civilization was established on the bank of Indus river. Indus river provides fertile tract in its bank which was the base of the civilization.

Explanation:

The main river and its tributaries and distributaries in the Indus Valley was a consistent source of resource to this civilization and to other civilization also.  The Indus River Valley Made the soil fertile enough with adequate texture and structure that it promotes healthy growth of crops and enriched production of it.  

It was started during early 2800 B.C. Indus is the longest river of Pakistan, on the bank of it Indus people was lived. The Indus river originates in Himalaya and ended at Arabian sea.

are there any options?