Roe 8, the first stage of the $1.65 billion Perth Freight Link (PFL), will extend Roe Highway from the Kwinana Freeway to Stock Road through the Beeliar wetlands.
Main Roads contractors began drilling near the intersection of Progress Drive and Hope Road on Tuesday morning.
About 10 police officers, including mounted police, cordoned off the area where work was being done.
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READ NOWPolice numbers more than tripled as the day progressed and more opponents to the road arrived.
Main Roads project director Terry Pearce said Main Roads was there to install bores as part of its groundwater monitoring program in preparation for Roe 8.
“We’re doing this work at the behest of the Environmental Protection Authority, with their approval and endorsement,” he said.
“It’s a condition of environmental approval (for Roe 8).”
Cockburn Mayor Logan Howlett called on Main Roads to cease work immediately.
“I’m aware of the approval but we believe that will be tested in the courts,” he said.
“There’s a court case pending which we believe will lead to the ceasing of this activity and the construction of Roe 8.”
Mr Pearce said he did not have the authority to cease work.
“We’re only working in cleared area so there’s no clearing, there’s no impact on the environment,” he said
“The information we get out of this will inform the Department of Water’s (DoW) database so even if the project didn’t proceed the DoW is a winner because it’s got more information about the water in this area of the Beeliar Wetlands chain.”
Mr Howlett said the information should have been gathered before environmental approval was granted.
Later in the week there were reports Main Roads had backed a tunnel option for the second stage of the PFL, linking Stock Road to Canning Highway.
Main Roads would not be drawn on the reports, but Federal Finance Minister Mathias Cormann told ABC 720’s Mornings program a decision for Roe 9 needed to be made sooner rather than later.
“The timetable which was agreed was that the whole project would get under way in 2016,” he said.
“We are still hopeful that we can meet that deadline, but there are some further conversations between the Commonwealth and the State in relation to the second part of the project.
“Our focus is to deliver the whole Perth Freight Link project, because in the end, we can’t just stop at the end of the Roe 8 extension.”
Melville Mayor Russell Aubrey said a tunnel option was supported by his council.