The driver, named Katrīna, was not injured in the accident. She said she was driving slowly in her BMW car and the road suddenly sank from beneath her.
She was able to leave the car after others helped her get out through the back door.
Eyewitnesses said the giant pothole had started forming beforehand but was not yet quite prominent before the accident.
The accident happened during hydraulic checks of the heating system, Rīgas siltums board member Uģis Osis told LTV. A pipe burst after pressure was increased in the heating network, he confirmed.
Osis said the company takes responsibility after the accident and will cover expenses together with the insurance company.
Linda Rence, a representative of the municipal heating company Rīgas siltums, said that this network had been installed in 1963 and is quite out of date. She said it's lucky the accident happened in the summer as during winter it might have become dangerous and left the entire neighborhood without hot water.