Middlemore problems outlined in documents, former DHB chair Lee Mathias says

Former Counties Manukau District Health Board chairwoman Lee Mathias says she doesn't know what Jonathan Coleman knows about the extent of problems at Auckland's Middlemore Hospital.

Coleman, the former Health Minister, has returned fire over claims he must have known about problems with buildings at Middlemore Hospital, including rot, mould, leaking sewage, asbestos and power supply issues.

Coleman told the Herald on Friday he had "absolutely no knowledge" of the problems at the South Auckland hospital.

And on Monday he told TVNZ he couldn't have known if officials didn't tell him.

Today, Mathias, who was chairwoman of the DHB between 2013 and 2016, said Coleman actually attended the opening of a clinic in one building after it was refurbished and partly remediated and they had had a conversation about its history.

There was a process for seeking capital investment which was followed and documents produced.

"Up until 2016 there were two major long-term investment plans done, one well before my time which certainly went through Wellington, and clearly identified all of the buildings that needed to be replaced on that site," she told RNZ's Morning Report.

Mathias pointed to one long-term investment plan completed for the site in November 2016 and the issues were contained in that document.

Asked whether she could prove Coleman was not telling the truth, she said: "I know what I know. I don't know what Dr Coleman knows. The facts are that there is a very established process for getting capital investment into district health boards and the staff followed that process."

She suggested ministers needed to make themselves available to DHB chairs so they could discuss pressing issues.

Coleman is stepping down as MP for Northcote, having accepted a job with private health provider Acurity.