A stocktake of Auckland's information technology systems has highlighted the huge challenge of abolishing Auckland's eight councils and moving to a Super City.

The complex wire diagram shows the challenge of merging different software products across a multitude of services into a single system to drive the Super City.

Mike Foley, overseeing the information technology changeover for the Auckland Transition Agency, said although councils often used the same software they operated it differently.

"It's like owning a Ford or a Holden. They may look the same but one runs on diesel and one runs on petrol."

The timeframe and cost of integrating the information technology system is unknown.

Councils spend hundreds of millions of dollars a year on information technology and have contracts that run for years.

Executive chairman Mark Ford said the agency would not have an optimal system in place when the Super City comes into effect on November 1 next year.

There was simply not enough time to hand over things like a new information technology system, he said.

Mr Ford said the goal was to maintain service levels for ratepayers from November 1 and, in some cases, improve service levels.

The agency, he said, aimed to have a blueprint ready for the new council to achieve efficiencies in the future.

The council is also expected to phase in a single rating system and user pays for water and wastewater.

When the Auckland Regional Council tried to introduce a single rating system in 2003 with rises of up to 467 per cent, it resulted in a rates revolt and regional council chairwoman Gwen Bull being tipped out of office.

Meanwhile, Rodney District Council chief executive Rodger Kerr-Newell has left the transition agency and returned to the council.

Rodney mayor Penny Webster said she had requested that Mr Kerr-Newell come back to focus on things such as a potential carve-up of Rodney.

Last week, it was revealed that the Government was looking to split Rodney District in two, leaving urban Whangaparoa and Orewa in the Super City and the area north of Waiwera to be merged with Kaipara District Council. Mr Kerr-Newell was seconded to the agency to be chief executive, but was given the title of "senior adviser" when Mr Ford decided on a day-to-day executive role.