Nearby residents have been given just 15 working days to respond to the plans under a consultation notice released by the government – the shorter period being made possible by the government's designation of the area as a special zone.

Health Infrastructure and Planning Deputy Director-General Jacinta George told a hearing on Thursday "we have preliminary sketch plans and a cost estimate and we have gone to tender for the head contractor".

Chief Minister Katy Gallagher said a price had been put on the 25-bed facility, unlike other capital works such as the hospital at the University of Canberra, as the government was "in a much later stage" with the project.

Some residents are unhappy with having the centre visible from their kitchen windows.

"Things people don’t want end up in the backyards of people in Symonston," the president of the Inner South Community Council (ISCC), Gary Kent, said. "There's a lot of heritage out there and it's vanishing before our eyes.

''The ISCC is not opposed to there being a centre, but we think it's being built in the wrong part of Canberra. We’re concerned about whether the place will be secure enough in terms of noise and impact.''

An amendment bill passed by the ACT Assembly this month removes the right of third parties to appeal to the ACT Civil and Administrative Tribunal.

Mr Kent said the special zoning will hinder any battle. "In some senses it's a bit of a done deal,'' he said. ''{But] we'll keep fighting on behalf of the residents."

Construction of the project on the site of the former Quamby youth detention centre is expected to begin early next year using funding allocated in this year's budget. Completion is expected towards the middle of 2017.