The State Parliament will be denied a chance to investigate the biggest motorway in the country's history after a Shooters and Fishers Party MP cut a deal to save a park near his inner west home.
Robert Borsak said he had agreed to vote against an inquiry into the $13 billion WestConnex after Roads Minister Duncan Gay committed to preserve Ashfield Park, which had been threatened by the motorway.
Mr Borsak said he had been asked by Mr Gay three weeks ago to block an inquiry into the WestConnex motorway. He said the agreement helped save the park and nearby Yasmar Estate.
''That's effectively what's happened, yes,'' Mr Borsak said.
Mr Borsak lives in Ashfield and had been a strong critic of the WestConnex and its potential traffic impact on the area.
The early stage of the motorway was to have emerged from a tunnel at Ashfield on Parramatta Road, carving up to 20 metres off the heritage-listed park.
Mr Borsak and other residents have also been concerned traffic from the tunnel at Ashfield would block local roads, at least until further sections of the motorway tunnel were built early next decade.
But the upper house MP said on Wednesday Mr Gay and WestConnex Delivery Authority chairman Tony Shepherd said in a meeting three weeks ago that major unannounced changes were planned for the motorway that would help traffic at Ashfield.
Mr Borsak had previously backed a request by Greens MLC Mehreen Faruqi into a call for papers on WestConnex.
But when Dr Faruqi proposed a select committee look into the motorway – examining the need for the project, its financing, environmental and transport impacts – Mr Borsak surprised some upper house MPs by not indicating his support.
On Wednesday, Mr Gay, Mr Borsak and member for Strathfield Charles Casuscelli held an event at Ashfield Park, inviting only local media, in which they announced the park would not be touched.
Asked later for details, Mr Gay would not say where the motorway tunnels would emerge. ''Shortlisted contractors will be directed to find innovative means to avoid it,'' he said.
Mr Borsak later said he had also secured an agreement to preserve the historic Yasmar Estate on Parramatta Road.
''They said they would guarantee Yasmar,'' Mr Borsak said. If the motorway encroached on the estate, he said: ''They would spend $4 million to $5 million on fixing it.''
Asked if he saved the park by agreeing to Mr Gay's request to oppose the inquiry, Mr Borsak said: ''You could probably say that, yes.'' He added that the government may have found ways to build the motorway cheaper without touching the park.
He said he had been convinced by Mr Gay an inquiry would be a waste of time.
Labor would back an inquiry into WestConnex, meaning the support of the two Shooters and Fishers members is needed to set one up.
Chris Elenor, the convenor of WestCon Community Action Groups, said he was ''disappointed and puzzled'' that Mr Borsak would not back an inquiry. But he said he was ''pleased that Yasmar and Ashfield Park have been saved''.
''Why is Gay so afraid of this inquiry?'' Mr Elenor asked. ''It's because the bloody thing has got no legs,'' he said of the motorway.
Dr Faruqi said: ''We shouldn't need political deals to protect our public parks and amenities.''
Asked if he struck a deal to save the park to prevent an inquiry, Mr Gay said: ''Mr Borsak has been a passionate supporter of Ashfield Park along with a large part of the community and the member for Strathfield Charles Casuscelli.''