Kaipara District Council (KDC) chief executive Louise Miller remains the only council management leader to remain.
Far North District Council's new chief executive Blair King started last month, while Whangārei District Council's new chief executive Simon Weston will commence his new role soon.
Northland Regional Council (NRC) staff find out today who their new chief executive will be in the wake of chief executive Malcolm Nicolson's upcoming departure from his role.
The staff announcement is on the same day as a short-notice extraordinary public excluded council meeting for NRC councillors, also attended by recruiters involved in the new management leadership appointment.
"This has not happened in Northland during my 55 years in public service," Carter said.
Carter said he was retiring from public service because he had done more than five decades of public service and would be 72 at the next elections.
Mai said three terms was enough for a mayoral position. Her three-term tenure follows a string of others' short-term mayor tenures previously.
Carter warned the volume and velocity of government change meant other mayors around New Zealand were considering the same action ahead of the October elections.
Three Waters, local government reform, major Resource Management Act changes and more were taking a huge toll, he said.
Carter said his decision to stand down would have come regardless of these changes.
Northland might be a magnification of what would unfold around the country in the wake of these changes.
Carter said the pressure was relentless.
Dr Andy Asquith, a former Massey University local government specialist and now an adjunct research fellow at Curtin University in Perth said the almost across-the-board leadership change was a seismic shock for Northland.
He said it meant huge amounts of experience and knowledge were being lost.
Such major changes happening so close together in the face of major Three Waters reform and other shifts added risk to local democracy.
He said councils were the most important and localised local democracy, close to the homes and lives of Northlanders and New Zealanders.
Asquith suggested other leaders around New Zealand would be at risk of following suit. New Zealand was already the most centralised government in the OECD.
He said everything about people's lives in their region was linked to councils – when people turned on the tap, when they flushed the chain on their toilets, the roads they drove on.
Carter said more and more central government cost was being loaded onto local government, and as a result to its ratepayers.
The major Northland political change becomes interesting when Three Waters restructuring is considered.
Far North, Kaipara and Whangārei District Councils are mooted to be combined into a huge top of New Zealand Three Waters service body called Entity A.
Auckland mayor Phil Goff has also announced he will not be standing at the next local government elections either.
That means that, if Kaipara's Smith is re-elected, he will be the only current Auckland North Three Waters political leader left standing.
Smith is currently the Northland Mayoral Forum chairman.
Carter is currently a Local Government New Zealand board member. He has also been Minister of Civil Defence and a New Zealand High Commissioner to the Cook Islands.
Carter said Northlanders had to make sure they researched to see who would be good candidates able to deal with a majorly changing local government scene.