The Point Grey Marina was put on the national stage by Canning MP Andrew Hastie, who set out his opposition to the project in a speech to Federal Parliament that stunned pro-development colleagues. In what he described as a postscript to his maiden speech, Mr Hastie said he supported "the sovereignty of local communities to make decisions about how they conserve and develop their environment". "We're not anti-progress, but we are rightly cautious about development, as we are the ones most affected by it," he said. The prominent government backbencher said the company behind Point Grey Marina had "no stake in our local community and should not be able to dredge our waterways without the consent of local people". Last week Mr Hastie told WAtoday and Nine News Perth he was preparing to spearhead a campaign to halt the development.

"We oppose the dredge outright," he said. "We do not want to see the estuary destroyed, we don't want to see habitats and local marine species damaged, especially our crabs. "People's livelihoods will be affected, local fishermen particularly, and we're called to be stewards. "It's our job to protect and preserve these wonderful things in our environment."

Mr Hastie is backed by state Labor MPs David Templeman and Robyn Clarke and Liberal member for Dawesville Zak Kirkup. Local Aboriginal elder Frank Nannup posted a video to social media opposing the marina. "The land around Point Grey, there are some spots there that are different, that you will never see in any part of the whole estuary system," he said. "It's unique. That's just the land. And if you want to start dredging the derbarl, well that's going to cause havoc again. "We don't need a marina there, you can put a marina anywhere, there is one nearly everywhere else."

The Shire of Murray, which is pulling every lever available to it to stop the marina project, and the City of Mandurah both said they would refuse to pay for the ongoing costs of re-dredging the navigation channel to the marina, if it was built. Mandurah Mayor Rhys Williams said the project would mean a "dirty great big hole in the middle of our estuary, one of our most important environmental, social and economic assets in this region". If you dig a hole in our estuary, it will fill with toxic black ooze ... Long term, it will be devastating. We believe this is the single biggest threat to the estuary. Peel-Harvey Catchment Council's Jane O'Malley "For the people in Mandurah and the Peel region, the Peel-Harvey Estuary is the lifeblood of the place," he said. "So we're saying in one voice, that this is our Estuary and the future of this estuary is too important for us to sit back and not be vocal in our opposition to this plan."

This week Tian An Australia will be taking the Shire of Murray to the State Appeals Tribunal to challenge a council decision to knock back development approval for the project. Shire president David Bolt said the project would have an impact on the local environment felt by people across the state. "Of all the submissions we received, not one of them was in support of the project," he said. "So the community are obviously very vocal about it, there's continuing to be more opposition, but the project is significant to the broader WA community. "I mean there are many who will come down and recreate in the estuary – people that crab down there and people that fish – and I think before this project goes forward we need to know what we're getting ourselves into".

Peel-Harvey Catchment Council chief executive Jane O'Malley said the development would be a catastrophe for the waterway and wetlands. "Science is showing our estuary is in a bad state," she said. If it goes ahead, the Point Grey Marina will require the dredging of a 2.5 kilometre navigation channel across the Peel-Harvey Estuary. "The state government has recognised it as an estuary at risk, the Commonwealth Government has put in a lot of funding into trying to restore the health of the estuary. "Long term, it will be devastating. We believe this is the single biggest threat to the estuary."

Ms O'Malley said an array of marine and bird life was at risk from the project. "You should be worried about dolphins," she said. "We have nearly a hundred resident dolphins within the estuary and we're already battling with litter. "Boat traffic will certainly be an issue as well and lot of our dolphins already show scars from coming into contact with propellers. "If you dig a hole in our estuary, it will fill with toxic black ooze."