Conservationists are warning a $2.7 billion development on the banks of the Caboolture River will threaten Moreton Bay's fragile ecosystem.
The development is near a wetland of international significance and home to the critically endangered Eastern Curlew bird.
Environmental scientist Ian Bell said the plan to dredge 5 kilometres of the river will create poisonous gases and exacerbate the growth of fish-killing algae.
"How can I not be concerned? I love the Bay— I've seen the deterioration of it over 50 years and we're coming to a tipping point," he said.
"Look at all the thousands of permanent jobs that rely on [Moreton Bay] for tourism and fishing. I've talked to the fishing people and they're worried about it."