Independent northern suburbs councillor Greg Petty proposed the coal seam gas mining-free zone at Monday night's meeting, initially asking his colleagues to support a total CSG ban for the local government area.

However, Lord Mayor Gordon Bradbery said this would be out of order, as the council was not the legislative authority for coal seam gas exploration.

Other councillors then jumped to Cr Petty's aid, helping him to work a motion that could be passed.

His move followed a long, and somewhat unproductive debate about climate change and air quality monitoring, which led Cr Petty to decline to speak on the matter.

No other debate followed and the motion was promptly waved through by all councillors.

Cr Petty said he was "delighted" by this support.

"I think it means that the council has taken on board the community's concerns about the issue of coal seam gas mining and extraction and, most importantly, adds weight to the recent state government's decision to cancel some licences south of Wollongong," he said.

While recognising the declaration of a CSG-free zone had no legislative impact, Cr Petty said it would put on record the council's stance.

The declaration follows a motion introduced by Lord Mayor Gordon Bradbery a fortnight ago, in which councillors agreed to thank the government for listening to their concerns about exploration and mining in drinking-water catchments.

Liberal councillor John Dorahy was also due to introduce a motion to thank the state government for its progress on stopping CSG exploration in water catchment areas on Monday, but this was deferred as he was unable to attend due to illness.