Ten people are in Canberra hospitals with COVID-19, with both patients in the intensive care unit requiring ventilation.
ACT Chief Minister Andrew Barr has announced an additional $14 million to boost immediate and longer-term mental health services.
This includes boosted support for people with eating disorders, alcohol and drug services, and Indigenous and social housing residents.
"It is one of the most challenging times our community has faced," Mr Barr told reporters.
He said the ACT government would include another $10.3 million in funding for key health services in the 2021-22 budget.
The federal government will also provide $2.5 million to support a Head to Health pop-up mental health clinic in the ACT.
ACT Chief Health Officer Kerryn Coleman said people under the age of 18 make up 31 per cent of the total 641 cases recorded in Canberra's Delta outbreak.
"In particular, those under 12 make up 17 per cent of all cases in the ACT. Another eight per cent are aged between 12 and 15. And then five per cent is between 16 and 18 years of age," she said.
The territory's lockdown is scheduled to run until 15 October.
With SBS News.
Readers seeking crisis support can contact Lifeline on 13 11 14, the Suicide Call Back Service on 1300 659 467 and Kids Helpline on 1800 55 1800 (for young people aged up to 25). More information and support with mental health is available at Beyond Blue.org.au and on 1300 22 4636.
Embrace Multicultural Mental Health supports people from culturally and linguistically diverse backgrounds.