Nigel Ackerman, from Palmerston North, said he was at the SH1 rest stop before Waitetoko Beach Reserve when he saw a grey utego off the road and into the water.
“We were just down here having a cup of tea,” Ackerman said.
“We heard this noise. Next thing you know he was in the lake.”
Ackerman said the ute came off the road and went about 10 metres into the lake.
“There was a car that has gone off the road into the water,” the spokesperson said.
“It appears it was a medical event.”
The spokesperson said members of the public pulled the person from the car before emergency services arrived at the scene in the Tauranga-Taupō area this afternoon.
A Hato Hone St John spokesperson said one person was transported to Waikato Hospital by helicopter in critical condition.
Maryana Garcia is a Hamilton-based multimedia reporter covering breaking news in Waikato. She previously wrote for the Rotorua Daily Post and Bay of Plenty Times.