A farmer who was first on the scene of a milk tanker crash in Ruawai believes the driver may have died in the cab before the crash occurred.
Colin Carter, of Tramline Rd, was driving up the road just after 9am on Saturday to tend his cattle, when he saw the truck in the drain.
He got out of his car and climbed on to the overturned truck to try to help the driver, who was trapped in the cab.
"He was still warm and I felt for a pulse, but there was absolutely no pulse."
Mr Carter said the driver was face down in the drain with water up to his shoulders.
"I grabbed his personal items and left them for the emergency services," he said "I just wonder how he got from behind the wheel to the passenger's side."
The local fire brigade turned up within minutes, Mr Carter said.
The accident happened in fine weather. The driver, who had not been formally identified yesterday, is understood to be a 64-year-old from Whangarei.
Speaking from the scene, Dargaville police Detective Sergeant Johathan Tier said the cause of the crash had not yet been determined.
The police serious crash unit found no other vehicle was involved, there were no skid or brake marks and speed was not likely to have been a factor.
Milk had to be emptied from both the tanker and trailer before cutting tools were used to separate the trailer from the truck, which was the lifted by a crane brought from Whangarei.
Mr Carter believed the road was closed most of the day and the crane worked all day to get the truck back onto the road.
Three milk tanker crashes have occurred in Northland in the past four months, including one fatality when a 14-year-old cyclist was struck by a tanker near Kawakawa.