The deaths of a man and his young daughter who fell from a dam wall in South Australia are being treated as a murder-suicide, police say.
Henry Shepherdson, 38, was seen by witnesses to jump from the Whispering Wall at Williamstown on Wednesday afternoon while holding nine-month-old Kobi in a child carrier.
Mr Shepherdson was found dead at the base of the wall and although the girl was helped by people who came to her aid and treated by paramedics, she also died at the scene.
Assistant Commissioner Ian Parrott said there was some history of domestic violence in the family, but Mr Shepherdson had lawful access to his daughter.
"Obviously this is a highly distressing and emotional set of circumstances," Mr Parrott said.
He said the mother was not present at the dam but had called the police emergency line within a short time of witnesses also calling triple zero.
"Clearly, they have had a child together, there was a relationship there but something has happened within that relationship," he said.
"For reasons that I think all of us can't fathom to understand, it's resulted in this tragedy."
Mr Parrott said it was now a matter of "unpacking" what led to the deaths with the investigation expected to be complex.
A report will then be prepared for the coroner.
The Whispering Wall is the retaining wall of the Barossa Reservoir, with the 36-metre high structure built between 1899 and 1903.
The popular tourist attraction was bestowed its name as words whispered on one side can be clearly heard at the other, more than 100 metres away.
WHERE TO GET HELP
• Lifeline: 0800 543 354 (available 24/7)
• Suicide Crisis Helpline: 0508 828 865 (0508 TAUTOKO) (available 24/7)
• Youth services: (06) 3555 906
• Youthline: 0800 376 633
• Kidsline: 0800 543 754 (available 24/7)
• Whatsup: 0800 942 8787 (1pm to 11pm)
• Depression helpline: 0800 111 757 (available 24/7)
• Rainbow Youth: (09) 376 4155
• Helpline: 1737
If it is an emergency and you feel like you or someone else is at risk, call 111.
