Srimad Bhagavatam Canto 10, Chapter 25, Text 10

SB 10.25.10

sthuna-sthula varsa-dhara
 muñcatsv abhresv abhiksnasah
jalaughaih plavyamana bhur
 nadrsyata natonnatam
 
Translation: 
 
As the clouds released torrents of rain as thick as massive columns, the earth was submerged in the flood, and high ground could no longer be distinguished from low.
Srimad Bhagavatam Canto 10, Chapter 25, Text 09
Srimad Bhagavatam Canto 10, Chapter 25, Text 11