Judge Mark Taft described the actions of the man, who is now aged 67 and cannot be named for legal reasons, as "repugnant and morally reprehensible" saying he believed they demanded a lengthy term of imprisonment.
During Thursday's sentencing the man, who appeared in court via video link, sat shaking his head and on multiple occasions put his head in his hands while Judge Taft described his callous offending.
The victims sat in court weeping as they listened to a recount of the offending which saw the man sentenced.
The court was told the assaults took place between January 2000 and December 2004 when the three victims were all aged under 10 years.
The court heard the man sexually penetrated his then partner’s daughter four times and committed an indecent act with her three times while she was aged between seven and nine at his home in Euroa.
He was also charged with one count of incest against his young daughter, as well as willfully committing an indecent act when she was aged between four and six years.
In 2004 he also sexually penetrated his daughter’s young friend while she was having a sleepover at his house.
The court was told the man could not remember the offending taking place, saying during a pretext phone call with his daughter's friend in 2017 "I can't remember doing that" and "I can only assume I would have done it in a drunken stupor".
Judge Taft referred to victim impact statements written by the three victims, stating the effects of the man's conduct upon them have been profound.
“What happened to me when I was a little girl killed me inside ... I've wanted to hurt myself over this, I've cried myself to sleep a million times,” one victim wrote.
When sentencing Judge Taft said he took into account the man's age and his poor health.
He acknowledged the man had been the subject of sustained sexual abuse by his half-brother as well as by a supervisor when he was in an institution.
Judge Taft said the man began consuming alcohol from 17 and by his mid-twenties he was consuming more than a dozen beers a day, along with drinking nearly a bottle of scotch per day for the past 20 years.
“I do not find your claim of not recalling the sexual offending as credible — in my view it is consistent with your pattern of avoidance rather then the events being obliterated from your mind as a consequence of intoxication,” he said.
Judge Taft said he took into account the man's early plea of guilty, his blighted background, age and poor health, and limited criminal history.
“You have corroded the childhood of three young girls, and the consequence of your behaviour has been life-altering,” Judge Taft said.
“They have been weighed down by the burden of their earlier silence and each must deal with their fears, their understandable lack of trust in adult males and their desire to avoid being the subject of idle discussion within the community.”
The man previously pleaded guilty to five charges of sexual penetration of a child aged under 16 years, four counts of an indecent act with a child aged under 16 years and one count of incest.
He will be eligible for parole in nine years and has already served 58 days of pre-sentence detention.
