Furtado and three others fell in the creek on June 26 during an inspection of weed cleaning process. The weeding machine-boat on which they were riding overturned, toppling them.
Panaji police then registered a case of accident.
"I told the police that it was a human error and I don't blame anybody," Furtado told PTI.
He said he had taken reporters along to demonstrate the cleaning process, so that people would become aware that they should not throw rubbish in the creek.
A local activist filed a complaint against Furtado after the incident, accusing him of putting lives of other people in danger.