Benjamin Young, 35, of Lower Hutt was killed when a car he was travelling in left the road and plunged into a Wairarapa river.
Tributes flowed on Facebook last night for Mr Young, who was remembered by friends as a "legend" who would be sorely missed.
"RIP brother Ben," read one post.
"So freaking ratshit to hear that a good mate has left us ... rest easy bro much love."
Another person commented saying their heart went out to Mr Young's friends and family, while others remembered him as a nice guy who loved cars.
"That guy was a legend," said one friend.
"Probably the fastest car on the Wellington scene bro you will be missed," wrote another.
The vehicle drove off Paierau Rd and into the Waipoua River, just north of Masterton, before 4am.
A rescue helicopter had to fly high above the car which was stranded in a raging Wairarapa river to ensure it did not knock off three people clinging to the roof.
Wellington Life Flight winch operator Julian Burn said the ensuing rescue operation was the most challenging he had ever been involved with.
"Once we got in the area we hovered probably 80ft (24.4m) above the car because we didn't want to get too low because we're putting out 110km/h winds from the rotor and there was the real hazard that we could have blown them off the roof of the car and back into the river."
Battling strong winds, he lowered a paramedic down to join the three terrified young people on the roof of the car.
The paramedic managed to clamber onto the windscreen and attach a harness to the first person, a young woman.
She was winched up into the chopper and the procedure was repeated twice to retrieve the other survivors. All three were taken to a waiting ambulance on the shore and transported to Wairarapa Hospital.
"As you can imagine they were hypothermic because they'd been on there for a couple of hours. They were cold and they were very emotional because they had just lost their friend," Mr Burn said.
The three survivors had done the right thing by staying on the roof and not trying to swim through the fast-moving river.
"It was white water, no question. And they only had a couple of inches from the roof to the water. It was very swift water," Mr Burn said.
"A job like that during the day time is hard enough but when you add night time as a factor using night vision goggles and things like that it just makes it harder.
"For me personally it was the hardest one I've ever done, just due to the factors: night-time, on the roof of a car, in a swift river, limited space, poor weather. But the pilot and the paramedic and the guys on the ground, all did a fantastic job."
A Wairarapa Hospital spokeswoman said the three survivors from the crash were in a stable condition.
Meanwhile, another person was killed when a car rolled on State Highway 2, Te Puke East Rd, near Pukehina in the western Bay of Plenty, shortly before 8am.
A police officer at the scene said the rear passenger was killed while the driver was in critical condition and was being airlifted to hospital
The front seat passenger was not seriously injured.
Maketu fire brigade Chief Fire Officer Shane Beech said there were believed to have been three occupants in the vehicle. Firefighters had to extricate one of them. He said they were in a bad way.
That stretch of State Highway 2 was closed and a reporter at the scene said there were at least five police cars and three ambulances in addition to the rescue helicopter.
A police communications spokeswoman said diversions were in place and people should be prepared for delays.
Motorists were advised to use Ohinepanea Rd and Old Coach Rd in both directions.
At Leeston in Canterbury, a vehicle hit a barrier near the intersection of Beethams and Volckman Rds around 7.30am and the male occupant had to be freed from the wreckage. A police spokeswoman said his injuries were not too serious.
About 8.30am at least one person was injured in a head-on collision on Laws Rd near the State Highway 2 intersection in Dannevirke.
A police spokeswoman did not know how serious the injuries were.
In Napier, a person had to be freed from the vehicle they were in after a crash near the intersection of Tennyson St and Kennedy Rd about 10am.
A St John spokeswoman said two people were transported to hospital, one with serious another with moderate injuries.