Today's announcement was the Government's response to the council's city centre recovery plan draft, which was drawn up with public consultation and proposed a $2 billion smaller, greener, low-rise city centre.
Mr Brownlee said part one of the plan would be largely accepted, although transport aspects would be "put to one side for the time being''.
Christchurch Mayor Bob Parker said installing the unit was the best way to handle the central city's rebuild, and called it a "true partnership''.
However, the plans have not been met enthusiastically by all, with opposition parties criticising the Government for railroading the council and creating further delays for rebuilding.
Ms Dalziel, who is based in Christchurch, described the unit as "yet another layer of bureaucracy''.
"The people of Christchurch needed to hear about a vision for the central city that reflected the ideas that the community expressed through the Share an Idea campaign. They needed timelines and milestones, not more stalling tactics,'' she said.
"The Government has wasted almost an entire year with ill-thought out processes. Now it has actually come up with a unit which has the potential to deliver the visionary master plan our city needs, but we have to wait 100 days to find out whether it lives up to that potential.''
Green Party earthquake spokeswoman Eugenie Sage, who lives in the city's Diamond Harbour, said the establishment of the unit risked overshadowing the work the council and the city's residents had already done.
Ms Sage said more than 100,000 residents had contributed to the development of the council's draft plan, and it was important their vision for the city was not lost.
"What is cheapest and quickest for commercial property owners will not necessarily create an attractive, enduring and sustainable city that is a pleasant place to work, live and play in.''
New Zealand First earthquake issues spokesman Denis O'Rourke supported the unit, but said it was important focus also remained on residential areas as plans to fix the city centre progressed.
The Property Council also supported the move, with chief executive Connal Townsend applauding the "common-sense approach'', and saying that he expected the move to encourage reinvestment in the area.
Warwick Isaacs, who is currently Cera's operations manager for demolition work, has been appointed to lead the rebuild unit.