Soft light glows from a sign in Phong Luu's Sydney unit: "Welcome to Nirvana".

He's made the one-bedroom apartment his own. Since moving in almost three years ago, he's scrubbed away mould, cleaned up the balcony, painted the walls and achieved his dream of a minimalist, inviting space he can share with friends and family.

But eventually, Phong will have to move. His landlord is the New South Wales government. And it's selling the estate he calls home.

"I was shocked and surprised, because I've just moved in here, created a really safe space, and also formed a really good community around me," Phong said.

"So to have this news that it's going to be knocked down … I feel angry, because the community here is so good."

Waterloo Estate is the biggest social housing estate in Australia. Its massive towers, terraces and single-storey cottages sprawl over 18 hectares close to Sydney's CBD, housing almost 2,500 people.

The site will be redeveloped under a NSW government strategy called Communities Plus, where public land is offered to developers on the proviso 30 per cent of what they build is dedicated social housing.

More than 51,000 households are waiting for a home in NSW. At Waterloo South — the first portion of the estate that will be redeveloped — only 100 additional social housing units will be built under the Communities Plus strategy.

"It's not big numbers by any stretch of the imagination, and certainly not anywhere what we would suggest is deserving and possible on a site like that," said Shelter NSW chief executive John Engler.

Communities Plus is supposed to help the state's Land and Housing Corporation "renew" ageing properties and boost supply while remaining cost neutral. In reality, it means the state is "cannibalising" its own stock, according to Mr Engler.

University of Sydney emeritus professor Peter Phibbs agreed.

"I think the dilemma with this strategy is that we're not really seeing any real increase in social housing in NSW, certainly compared to other states," he said.

"And that's having a really negative impact on all those people on the waiting list who just can't get into social housing, because there's just really no new net supply."

In response to questions from 7.30, the Land and Housing Corporation (LAHC) said only 2,773 new social housing properties of a planned 23,000 had been built since 2016.

'They can take me out in a bag'

Olivia Bright has called Waterloo Estate home for more than 30 years. On the walls of her apartment, she and her friends smile in glamorous photos from decades past alongside shots of old Hollywood stars like Marilyn Monroe and Elvis.

The tower Olivia lives in may not be redeveloped for decades – but the 69-year-old is readying herself to move anyway, just in case.

"When they take me, they can take me out in a bag," she said.

Olivia's best friend, Luna Farrell, lives two floors above in the same tower block.

Luna is neither for nor against the development, acknowledging living at the estate was "not the best, but manageable".

"With the people who don't want to move, I understand why because this has been their home for the last 50 years or so, so having to pack up everything, relocate then unpack everything is going to take a toll on them," Luna said.

"But on the other hand, I do see why it is important for the redevelopment to go ahead because it's progress."

It's not yet clear when plans will be released for the central and northern parts of the Waterloo Estate.

Residents of Waterloo South expect to be told when and where they will be moving later this year.

Phong, who lives in that section of the site, believes not enough information has been provided to him and his neighbours. He was under the impression he may have to move next year, until 7.30 asked the Land and Housing Corporation, which said he would not.

"I feel that there's a bit more that they don't know, that they're not disclosing, because a lot of tenants are confused whether they have the right to come back or not," Phong said.

The government has repeatedly promised that current Waterloo tenants who want to return to the estate will be able to do so. It has also pledged to give residents at least six months' notice before their move.

A spokeswoman told 7.30: "Resident relocations will occur in small stages over the next 10 years, with the first stage to take two years, and LAHC (Land and Housing Corporation) will provide details to residents this year regarding the start of the relocation program as well as which buildings will be selected."

Housing solution 'not rocket science'

Professor Phibbs, a nationally-recognised housing expert, said NSW was trailing the pack when it came to building new social housing.

"It's not rocket science," Professor Phibbs said.

"All really we've got to do is invest … but in recent years, we just seem to have lost our appetite for that in NSW."

In a statement to 7.30, a spokeswoman for NSW Homes Minister Anthony Roberts said the state government had invested $9.3 billion in the sector during the past five years.

"We will continue to work towards the best social outcome, which is mixed communities with social, affordable and private housing in every community," the spokeswoman said.

But Shelter NSW believes Saturday's state election is an opportunity to rethink plans for Waterloo Estate — and other sites slated for redevelopment under the Communities Plus model.

Waterloo is one of more than 10 Sydney social housing sites facing redevelopment under the strategy.

"The world's changed considerably with the Commonwealth's commitment to bring online 30,000 properties by working with the states," John Engler said, referring to the federal government's pledge spanning the next five years.

"We certainly hope that whoever wins government in NSW in March, leans in, looks at the policy that is Waterloo and the inner city and our approach to housing and … comes up with a more exemplar opportunity, something that we can all be proud of, rather than say 'that's the best we could do'."

The state opposition has pledged to review Communities Plus projects if it wins government on Saturday.

Labor housing spokeswoman Rose Jackson said in a statement: "Communities Plus has been a failure, with only a fraction of the promised social and affordable housing actually getting built."

LAHC said "external factors including natural disasters, COVID and local government planning controls" had affected its ability to meet housing targets, but said money had been spent upgrading existing stock — allowing for the retention of more than 9,000 homes that would have otherwise been sold or demolished.

Luna Farrell has a message for whoever wins the state election.

"Why don't they first get off their backsides … and fix up the places that have been empty for over six months," she said.

"They need to give more homes to people who can't afford the private rental market."

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