Joseph El Jer, 40, attempted to drive across a flooded causeway between Narromine and Tullamore, in the NSW Central West, on the afternoon of September 23, 2022.
He managed to escape and pull three other passengers to safety when the ute was swept into Graddle Creek, but a five-year-old boy became trapped in his booster seat.
Police divers pulled the child's body from the water the next day.
More than three years later, El Jer was surrounded by supporters as he faced Parramatta District Court on Friday after pleading guilty to dangerous driving occasioning death.
The 40-year-old has a lengthy driving record including 12 disqualifications, the last of which was imposed four months before he decided to cross the river, the court was told.
He ignored road closure and caution signs as he drove towards the causeway, where the floodwaters peaked at up to 1.3m above the road.
El Jer drove his ute into the waters but then reversed so he could wade into the water to assess whether it was traversable, according to the agreed facts.
He then made the risky decision to proceed, but the ute's engine stalled during the journey and the car was swept away by the fast-flowing water.
"The offender (made) a grave misjudgement about whether it was safe for him to drive the vehicle through the floodwaters", Judge Philip Ingram told the court.
"That misjudgment gave rise to catastrophic circumstances which culminated in the death of the deceased."
The judge noted El Jer was genuinely remorseful for his actions and had good prospects of rehabilitation if he engaged with treatment for his risk-taking behaviour.
The driver was sentenced to just more than one year and one month imprisonment to be served in the community and directed to perform 500 hours of community service.
Judge Ingram also ordered El Jer to complete counselling for his risk-taking behaviour and his prolonged grief, issuing him a stern warning not to drive where he shouldn't.
"You're getting out of here by the skin of your teeth today," he said.
"It would be a really good time for you to stop taking risks."
El Jer is suspended from driving for three years, marking his 13th disqualification while holding a NSW licence.
