Most of the New Zealand Transport Agency's Northland staff would also join the NTA, based primarily from Whangarei's Walton Plaza, though councils would still employ their own staff, based throughout Northland.
Far North Mayor John Carter said any jobs relocated to Whangarei from elsewhere in the region would be replaced through future projects where the councils looked to collaborate.
"We've been careful around that ... We want to ensure that staffing is spread across the north," Mr Carter said.
He said it was important for councils to maintain their "political independence" as they explored shared service options.
Northland Regional Council chairman Bill Shepherd said the NTA was about doing more for the same amount of money, rather than reducing the amount each council spent. Smaller businesses could be protected through a compulsory component of subcontractor involvement as contracts became larger. The four councils spend about $86 million a year on roading and transport.
The NTA was the first major initiative to come out of the Northland Forward Together strategic collaboration, which the four councils ratified late last year. Around that time then-Local Government Minister Paula Bennett said regions that looked at integrating their core services could be in line for a infrastructure funding "top up".
Ms Mai said she did not see this as a "dangled carrot", however there were situations where the Government had funded work in Northland in exchange for evidence that councils were collaborating. The councils were also investigating the benefits of using the same IT and rates collection systems.