Initial geotechnic testing has been carried out on the site for the 52-level NDG Auckland Centre, to be New Zealand's second-tallest building after the SkyTower, and construction might begin next year.
A drilling rig was on the carpark accessed off Elliott St between Albert St and Victoria St West a fortnight ago and experts were examining conditions.
Mayor Len Brown announced last year that resource consent had been granted and that Shanghai multimillionaire Furu Ding would build the tower which Brown said would transform the area and enhance his planned City Rail Link.
"Alongside the SkyTower, this will be a world-class development for Auckland that will create hundreds of new jobs, energise the CBD and boost Auckland's GDP, through a more than $350 million investment by NDG. It's also an example of the major commercial opportunities created by the City Rail Link project," Brown said at the time.
James Kellow of NZ Mortgages & Securities said earlier this year that big empty sites were bad for the city.