A foster carers' backyard pool where toddler Braxton Slager drowned was "distinctly green in colour", installed without approval and was not up to Australian standards, an inquest into the child's death has heard.
An inquest is looking into how 22-month-old Braxton drowned at a north-western Sydney house in September 2014 after being in foster care for three weeks.
Counsel assisting the coroner, Gerard Craddock SC, handed out a statement of facts to the court which said foster carer Julie Tarlinton had checked Braxton's room that day and he was not there.
"She realised it was too quiet … she saw him in the pool," he said.
The court heard Ms Tarlinton screamed, before she attempted to resuscitate Braxton.
"Just how he was able to open the heavy, sliding door is not known," Mr Craddock said in his opening statement.
Mr Craddock said that if second carer, Greg McBride, locked the door the night before as he had disclosed, then "someone must have unlocked it".
"Anyone who had anything to do with Braxton knew that he was a climber."
Backyard mess of 'tools, nails, beer cans'
The statement Mr Craddock provided said several people who saw the Stanhope Gardens backyard observed: "The cleanliness of the residence was substandard, police who attended the scene described the house as 'messy and untidy' and the backyard was 'messy, dangerous to children and similar to a dumping ground'."
"The pool was filled with dank water, distinctly green in colour," Mr Craddock said.
"The backyard contained multiple items, such as discarded building materials, tools, nails, metal objects, alcohol and beer cans."
The first witness was Andrew Bromley from the community group Life Without Barriers that chose the boy's foster home.
Mr Bromley said he would conduct safety inspections at properties and "the majority of the time we would be in the living room which would be immediately by the front door".
"That involves looking through every room and the backyard."
Mr Bromley said he inspected the property a year before Braxton died.
Counsel assisting: "Did you see a swimming pool?"
Andrew Bromley: "No."
Counsel assisting: "Are you sure you didn't see a swimming pool?"
Andrew Bromley: "I have no recollection of seeing a swimming pool."
Case in 'public interest'
Family and Community Services sought public interest immunity, which would ban media coverage of documents relating to its investigation and death review report.
The ABC opposed that, arguing it was in the public interest to examine these aspects of the case.
Deputy NSW Coroner Harriet Grahame agreed and said there was enormous public interest in reporting what caused the death of a vulnerable child in state care.
The court heard the boy's parents were struggling to overcome drug problems, but that the child's father was expected to resume his role as primary carer "within weeks".
"Whilst Braxton's dad had his problems … he was Braxton's dad and they respected that bond," Mr Craddock said.
The inquest continues.