Srimad Bhagavatam Canto 01, Chapter 13, Text 52

SB 1.13.52

srotobhih saptabhir ya vai
svardhuni saptadha vyadhat
saptanam pritaye nana
sapta-srotah pracaksate
 
Translation by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada: 
 
The place is called Saptasrota [“divided by seven”] because there the waters of the sacred Ganges were divided into seven branches. This was done for the satisfaction of the seven great rsis.
Srimad Bhagavatam Canto 01, Chapter 13, Text 51
Srimad Bhagavatam Canto 01, Chapter 13, Text 53