In Madhya Pradesh capital Bhopal, 11 people died when two boats carrying an idol for immersion in a lake in Khatlapura capsized.
Seventeen people were on the boats when the incident took place around 4.30 am, the Bhopal district collector said, adding that six of them were rescued.
Six of the dead in Madhya Pradesh were in their 20s, while two were minor.
One of those rescued said that safety equipment was not provided to the devotees venturing into the lake to immerse idols.
Prime Minister Narendra Modi expressed grief over the death of 11 people in the boat capsize. "The capsizing of a boat at Khatlapura Ghat in Bhopal is saddening. In this hour of grief, our thoughts are with the families of those who lost their lives," the Prime Minister's Office tweeted quoting Modi.
Chief Minister Kamal Nath ordered a magisterial inquiry and a compensation of Rs 11 lakh each to the kin of the deceased. The police have registered a case against the two boatmen.
In Maharashtra, at least 18 people drowned in separate incidents during the immersion of Ganesh idols.
Immersion of Ganesh idols, which began on Anant Chaturdashi on Thursday, continued till Friday morning.
Drowning incidents were reported in 11 districts -- Amravati, Nashik, Thane, Sindhudurg, Ratnagiri, Dhule, Bhandara, Nanded, Ahmednagar, Akola and Satara, an official said.
Four people drowned in Amravati, three in Ratnagiri, two each in Nashik, Sindhudurg and Satara, one each in Thane, Dhule, Buldhana, Akola and Bhandara. Majority of the deceased were young, they said.
In Navi Mumbai, seven people sustained injuries due to a short-circuit when wooden top of a Ganesh idol's seat touched electric wires under a bridge.
Two men and two women drowned in the Yamuna river in Delhi during Ganesh idol immersion, officials said.
The Fire Department received information regarding the drowning around 9 pm on Thursday, officials said.
A fire tender was rushed to the spot and a rescue operation initiated. The bodies were subsequently recovered, they said.
The deceased, in their 20s, were residents of Nihal Vihar, Nangloi, they added.