"With the death of his wife Pat Warren in March 2000, this is added grief for his son Reece and daughter Keeley, grandchildren April, Grace Tom, and the extended Warren family."
Ms Brosnahan said ARC deputy chairman Philip Sherry would take over as acting chairman immediately.
Mr Warren grew up in the Auckland suburb of Kingsland and went to Mt Albert Grammar School.
The influence of a jazz trumpeter uncle, Jimmy Warren, led him into the music and show business scene.
He discovered and recorded rocker Johnny Devlin and promoted Kiri Te Kanawa and Ray Columbus.
He brought more than 500 overseas acts to New Zealand before a business collapse in the inflationary 1970s, when he sold his Kohimarama home to pay debts but kept his Rolls Royce and a chain of nightclubs.
Mr Warren survived a heart attack in 1999, knocking off booze and shedding a lot of weight.
Regional Council staff were told of Mr Warren's death by email about 12.30 pm.
In local politics, he rated as one of Auckland's most astute operators. His gruff gentlemanly charm belied a tough hard-headedness and no-nonsense leadership style.
He assured himself of another stint as leader of Auckland's environmental watchdog after he took on oil giant Mobil last year.
Demanding Mobil fall in with the other three major oil companies and lower sulphur content in diesel for Auckland, Mr Warren waged a boycott campaign against the company complete with full-page ads in the Herald and appearances on prime-time television.
It was a publicity feast for the ARC and Mr Warren in particular.
He was re-elected to the ARC last October with the biggest majority of any ARC candidate.
Although councillors, not voters, elect the chair, even his detractors admitted Mr Warren was a shoo-in in the aftermath of the Mobil campaign.
He was made a companion of the Queen's Service Order in 1994.
The family has requested that no flowers be sent. Mr Warren would have preferred donations to be sent to the SPCA of which he was a past president or the Cancer Society.
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