The odd days after Ganesh Chaturthi are considered auspicious for immersion and Monday being the third day saw people with Ganesha idols making a beeline to the tanks.
Members of youth associations, dancing in a processions and hundreds of vehicles making their way to the tanks, stalled the traffic. Roads leading up to the tanks were  made one-way zones on Monday evening.
Madhukar Shetty DCP (Traffic) East, said Gangadhar Shetty Road, Annaswamy Mudaliar Road up to War Memorial was made a one-way to prevent traffic congestion near Ulsoor lake immersion area.
There were traffic restrictions on Sankey Road as well. As many as 9,200 idols had been immersed in Ulsoor lake up to 2 pm on Monday. BBMP officials said the number could go up to 22,000.
More than 7,000 idols were immersed in Sankey Tank. In the last three days, 60,000 idols have been immersed there.