Mr O’Connor, who was set to stand for re-election to the ward, died on Wednesday, August 6.
In a statement, Waimate District Mayor Craig Rowley expressed deep sorrow at the loss of a respected colleague and friend.
"We are heartbroken. Tom was not only a dedicated councillor but a man of great wisdom, empathy, and integrity.
"His absence will be felt deeply — not just within council chambers, but across the entire district. We extend our heartfelt condolences to Tom’s family, and all who knew and loved him."
Mr O’Connor had served on the Waimate District Council since 2013 and was instrumental in shaping initiatives such as the St Andrews/Southburn/Otaio Civil Defence Emergency Management Community Response Plan.
Outside of his council work, Mr O’Connor was a writer and historian, contributing political and historical columns to the several newspaper publications, and had also published numerous books. He was a reporter with The Courier in Timaru for some years.
He served as a Justice of the Peace, a former president of the New Zealand Grey Power Association, and was a long-standing member of regional Fish & Game councils.
In 2018, he was appointed a Member of the New Zealand Order of Merit in recognition of his service to seniors, local government, and journalism.
— Allied Media
