Police will not say if they plan to charge a pensioner over the crash near Sumner which tragically killed his wife, 73-year-old Maureen Imrie.
Bruce Imrie was driving home with his wife in the afternoon on March 25 when he crashed.
Witnesses saw the car drive straight off the road, crashing through a barrier and down a bank into the sea.
They were able to pull Mr Imrie out of the car, but the car was swept away by an undertow before they were able to rescue Mrs Imrie.
A police spokeswoman said the investigation into the crash was still ongoing. She would not say if police were considering laying charges.
It comes as West Coast man Michael Saunders is facing charges over the death of his 2-year-old daughter, Emily, who was swept from the sport utility vehicle he was driving across a flooded river, and the death of Barry Petrie, 66, who died while trying to save her.
Last year Christchurch man Tula Ram Chhetri was charged and convicted of dangerous driving causing death over the crash which killed his wife, Mon Chhetri, and baby son, Aaron Chhetri.
He had been driving the family home to Christchurch, and pulled out in front of another car at an intersection.
Mr Imrie said he was not worried by the investigation, but just hoped it would be completed soon.
He said he had told police all he could, but said he had "blanked out" before the crash.
He said he was still struggling with the loss of his wife of 55 years, but was being supported by his family.