Warrnambool councillors say they are shocked and disappointed that Peter Hulin has decided to step down more than six months out from the next election.
Mr Hulin on Thursday resigned as a councillor citing a lack of openness and transparency and a toxic culture within the council.
Cr Robert Anderson said he was in "total shock" when he received an email from council chief executive officer Peter Schneider with the news.
"Peter's had a few issues over the 11 years he's been on council but...it's come out of the blue," he said.
"I'm shocked and disappointed. He always puts his point of view, which is good. It's something we don't need at this moment, but he's chosen to do that." He said Mr Hulin would be missed.
Cr Sue Cassidy said she had learnt a lot from Mr Hulin since she had been on council.
"He's always been open, happy to help and he's had some great ideas," she said.
"It's just a shame that some of his ideas don't get up. It's disappointing. But it has come to this that he feels that he does have to leave."
Cr Kylie Gaston said she wished Mr Hulin the very best for his future.
Mayor Tony Herbert said he was disappointed but wished him "all the very best". "I'm not glad he's done it," he said. "He has got a lot of good ideas."
Cr Herbert said he had supported some of Mr Hulin's ideas, including seconding his successful motion last week to consider some form of free car parking in the CBD at Christmas.
"He has done some good things. He has listened to people. He has tried hard. He's often put a different point of view which encourages people to think a little bit outside the square. All those things are good," he said.
He said he wanted the council to get another few achievements "under its belt" before the end of its term.
"It has been tumultuous at times...at the end of the day the council has generally done very well, especially in a safe Liberal seat," he said pointing to the millions of dollars of funding for the library hub and Reid Oval.
"It hasn't been a complete waste of time for any of us and I think Peter's support and resilience has been important in that."
Cr David Owen said he wished Mr Hulin all the best. "He only had six months to go really, I suppose it's his way of exiting I guess," he said.
Cr Owen said he believed councillors were working together, and Mr Hulin's comments about council officers was "uncalled for".
"They're very hard working people and very thorough," he said.
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