A climate emergency was declared in Warrnambool on Monday, but one councillor voted against the motion.
Cr Peter Hulin, who said he was "biggest environmentalist going", said he voted against the motion because he believed the council needed to lead by example and it hadn't done that.
"If you can't do it yourself, you have no right to handball it to someone else," he said.
The motion was passed after a 40-minute debate in front of an audience of more than 50 people, many who had come just for that vote.
Members of the newly formed group Extinction Rebellion gathered outside the council chambers carrying a poster declaring "now means now", and applauded the councillors as they gave their speeches.
Member Steve Veale said they were there to demand the council declare a climate emergency.
The council motion recognised that we are in a state of emergency and urgent action was required by all levels of government.
They will write to the state premier and prime minister seeking action on reducing greenhouse gas emissions and meeting the Paris Agreement target.
The motion passed despite councillors Robert Anderson, Peter Hulin and Sue Cassidy questioning the use of the term emergency.
Cr Cassidy said it wasn't the easiest motion because there were so many different opinions from both sides.
However, she said that while the city was ahead of many others in terms of its environmental policies, they needed more funding to enact them and that required getting all tiers of government onboard.
"It all takes money that local councils don't have. We need to make a noise.
"I must admit I'm still not sold on the climate emergency name, but how can I ignore 1500 adults and children on our civic green."
Cr David Owen said the motion to declare a climate emergency it was possibly the most important decision the council would ever make.
He said the council needed to send a powerful message to the Australian government.
He said the urgent declaration would ensure all council's strategic decisions, approaches to planning and budgets would be made with the climate emergency in mind.
He also said the council's goal to reach zero emissions by 2040 was a decade too late.
Cr Kylie Gaston said she had been contacted from all different people from all walks of life in support of the motion.
Cr Mike Neoh said that given the council had adopted the green plan think it would be hypocritical not to adopt the motion.
"We all drive cars when we probably can walk. It's all our responsibility to make an effort no matter how big or small."
Cr Hulin said that anyone who doesn't acknowledge there was an issue with our environment had been living under a rock.
He said the council should lead by example and over 10 years on council he was disappointed that that hadn't happened.
He listed a number of environmentally-friendly projects that had been overlooked by the council including using geothermal energy to heat Aquazone.
"We are tonight effectively getting the environment and handballing it to someone else," he said.
"I personally think it's a real cop out for us as a community."
He also labelled some of what the council had done for the environment as tokenistic.
He also took issue with a council decision made last week to install a floating pontoon in a known platypus colony - a decision that would effectively kill the five that live there.
Mayor Tony Herbert said that even if you don't believe the science, we should all have a basic human instinct of wanting to look after and care for the world we live in.
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