The Buncrana pier tragedy was an accident waiting to happen, a victim’s partner said.
She said: “My heart is shattered.”
A jury found her family was drowned and died by misadventure following a harrowing two-day inquest in the Co Donegal town.
Driver Sean McGrotty was more than three times over the drink drive limit during the tourist town tragedy in March last year, post-mortem results showed.
The steep slipway down which the helpless occupants slipped was covered in treacherous and ice-like green algae and the car plunged uncontrollably into the water.
The only survivor was the four-month-old Rioghnach-Ann, daughter of Mr McGrotty and Ms James. She was passed over to a rescuer by her father before he was sucked underwater with the vehicle - getting back inside to be with his family.
Ms James said he was a wonderful partner and adoring father:
“He lived for them and it is clear from what this inquest has heard that in fact he died as he lived, in that he could have saved himself and chose not to.”
She felt “disbelief, pain and anger”.
“I firmly believe the slipway should have been closed to the general public or else proper warning signs displayed as it was an accident waiting to happen.
“Hopefully lessons will be learned and the recommendations made following this inquest will be implemented.”
The driver, his eight-year-old son Evan, 12-year-old son Mark, mother-in-law Ruth Daniels, and her teenage daughter Jodie Lee, 14, died when the SUV sank in Lough Swilly.
The spokesman for the five men and four women on the jury urged the Irish Water Safety promotional organisation to take a prominent role in advising and working with all interested parties on implementing best international practice for safety on all slipways and piers.
Misadventure means jurors think there was risk associated with the events that day and somebody had done something that increased the risk of the event happening, coroner Denis McCauley said.
There were no signs at the slipway warning of the dangers of slipping and a gate designed to control crowds using a summer ferry service in the popular tourist spot was left open.
It was used by people watching the sun going down despite dangers highlighted during the inquest.
The car was seen drifting out into Lough Swilly and bobbing around 20 metres from shore as children screamed for help before it finally sank three metres deep, eye witnesses said.
The inquest was told the doors of the Audi car would not open when an RNLI diver tried them and a window was only partly down, suggesting the electronics failed at some point due to the water.
Former footballer Davitt Walsh swam out into the harbour and rescued baby Rionaghac-Ann.
Garda Inspector David Murphy told the inquest: “Davitt Walsh is an ordinary man who did an extraordinary thing.”
He paid tribute to rescuers who arrived within minutes at a tragedy which impacted the whole of Ireland.
“Their actions are the truest reflection of the unstinting service provided by An Garda Siochana.”