The scheme was announced last week as part of the Budget in an attempt to help stem Auckland house price inflation which is currently running at 18 per cent because of a severe housing shortage combined with immigration pressure and near record-low interest rates on home loans.
Dr Smith said about 500ha of surplus Crown land had been identified across Auckland with "potential" for private housing development.
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Pushed to reveal the locations of the other 470ha, he said it was too soon to be definitive as due diligence checks on factors such as infrastructure and zoning were yet to be completed.
However, he said he was not prepared to let viable city land sit idle while first home buyers were shut out of the market.
"My view is to have land sitting around ... when people are paying over $800,000 for a home is a crime."
The most advanced of the four land parcels unveiled today is a 9.5ha site at the corner of Moire and Granville roads in Massey East where 200 homes could be built.
The land was being purchased from the Education Ministry and gazetted for housing purposes under the Housing Act. It was close the Royal Rd on-ramp to the North Western Motorway and located on major bus routes near parks, a shopping centre and schools. It also had access to existing water and wastewater infrastructure meaning development could proceed more quickly.
"I hope to have a development agreement signed before the end of October, earthworks started over summer and the first homes completed in late 2016," Dr Smith said.
The other three NZTA-owned sites could accommodate about 400 homes and were also being considered for purchase.
A 1.4ha site at Wiri Station Rd, Manukau could see 60 terraced houses built, a 0.4ha site near Pak n'Save in New North Rd, Avondale could see 60 high density houses built, and an 18ha site at Brigham Creek Rd, Hobsonville could accommodate up to 280 homes.
Dr Smith said in most cases developers who partnered with the Government would not have to pay for the land until the houses had been built and sold, enabling a broader range of development partners and removing upfront finance restrictions.
But the Government would stipulate that a proportion of homes be built in the HomeStart affordable range - likely to be under $550,000. It would also set strict timeframes for houses to be built to prevent landbanking.
"What government is making plain is our objective is pace, our objective is the number of houses and our objective is affordability."