Labor has promised almost $80 million for the treatment and support of children with mental health issues if the party wins South Australia's March state election.
The commitment was made as parents rallied on Saturday, calling for a cultural shift to better care for children amid what they say is a growing mental health crisis.
It also came as a Newspoll put Labor firmly ahead of the Liberal government, 53 per cent to 47 per cent on a two-party basis, three weeks out from election day.
Opposition Leader Peter Malinauskas, who spoke at the rally, said Labor would spend $7.8 million on more child psychiatrists and psychologists, $20 million on 10 new mental health beds at the new Women's and Children's Hospital and $50 million to recruit 100 specialists in child mental health to work in schools.
"The health and wellbeing of our kids including their mental health should be our top priority as a community," Mr Malinauskas said.
"The stories from South Australian parents struggling to get care for their kids are just heartbreaking."
Ahead of Saturday's rally, advocacy group Parents for Change said every week children in crisis were being turned away from hospitals while the state's child and adolescent mental health service had intolerably long wait times.
"Thousands of young people are being denied care at every access point," spokeswoman Kate Stephens said.
"In a crisis, they are being sent home with no support, no referrals and no follow-up care.
"In a first-world country, this is unacceptable."
Also on the campaign trail on Saturday, Premier Steven Marshall said a returned government would spend $27.5 million to revitalise Adelaide's River Torrens and its linear park trail making it healthier and safer for families, walkers and cyclists.
"The River Torrens is an iconic waterway and we want to transform it into a tourist hotspot that will impact positively on business in the suburbs, the CBD and at the beach," Mr Marshall said.
"We want to see recreational fishing return to the banks of the River Torrens and an upgraded, safer linear park that entices people from around the state to take on what will become an incredible, picturesque trail."
The premier also flagged turning a disused quarry in Adelaide's northeast into a 350-hectare adventure park for water activities as well as walking, hiking and biking.
The government has entered commercial negotiations with the owner to explore public access to the Highbury site.
The initiatives came as the premier played down the latest Newspoll, saying they bounced around and the only one that counted was the one on election day.
"But it does make it very clear to the people of South Australia that this is going to be a tight contest," he said.
"People make up their mind as they get closer to the election and I have every confidence that people will look at our track record over four years, they'll look at the track record of Pete Malinauskas and the Labor over the previous 16 years.
"When they weigh those two things up they'll realise that there's a lot at stake."
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