Residents from a seaside suburb in WA's south say they have had a big win in their decades-long battle to rid their otherwise pristine beach of stinky, rotten seaweed.
The community of Port Geographe, in the tourist city of Busselton, has been the epicentre of a colossal build up of seagrass every year since a poorly designed marina breakwater was built in the early 1990s.
Millions of dollars has been thrown at the problem over the years, which included a re-design of the marina and trucks moving the seaweed further down the beach.
The putrid stench that came from the rotting seaweed in the summer months has long been blamed for local health and environmental issues.
A 2019 storm that left 20,000 cubic metres of seaweed on the beach became a flashpoint in the saga, triggering a change of tack from authorities about how to manage the problem.
Western Beach Residents Association chair Jud O'Brien said criticism about a lack of planning from the government and developers resulted in residents being brought in to help solve the problem.
Mr O'Brien said the beach was clear of seaweed for nine months last year, which was close to what was natural for the Busselton coast.
"The beach was deplorable [in 2019], it was an unusable amenity," he said.
"The local resident groups demanded this change and we're getting it and we're close to realising all the benefits that this coastline can deliver.
"This is a good news story."
Mr O'Brien said techniques such as "slotting", which involved a bulldozer ploughing channels in the seaweed, had made a big difference.
"The waves can then get up towards the side and the back of the seagrass and pull it out much more efficiently," he said.
"It's about doing basically 1 per cent of the work, so nature can do 99 per cent of the work."
Department of Transport coastal facilities director Donna West said she hoped this year would be the same.
"The department was pleased to receive feedback from local community group leaders who believed the successful works provided the best beach amenity since the construction of the Port Geographe breakwaters in the mid-1990s," she said.
"Works can be expected during winter and spring months in targeted short campaigns."
Long and smelly history
It hasn't always been solely about addressing beach amenity.
The original design of the marina had rock structures heading straight out to sea, which interrupted the natural migration of seaweed down the coast.
The initial environmental approval predicted some unnatural seagrass accumulation and suggested mechanical intervention would be needed.
But the extent of problem was underestimated.
Three-metre-high mountains of seaweed engulfed Port Geographe's western beach, with the shore resembling more of a construction site than its previous pristine state.
Excavators loaded seaweed into trucks, where it was then dumped onto neighbouring Wonnerup beach.
Then came the smell.
Remaining seagrass began to rot as the temperature rose, polluting the air and water with hydrogen sulfide — known as rotten egg gas.
WA health advice says exposure to the gas can lead to nausea, vomiting, eye irritation and minor impacts to breathing.
Mr O'Brien said the subsequent health and lifestyle impacts inflicted a massive toll on the community.
"I can safely say there's been a lot of trauma in the community over the last 20-odd years," he said.
Even a redesign of the marina that was completed in 2015 failed to solve the issue entirely.
The new curved breakwater caused less seaweed accumulation but the western beach was still inundated with enough seaweed to cause severe amenity issues.
More work left to do
City of Busselton mayor Grant Henley said he was relived the worst of the problem had passed and urged the community collaboration to continue.
"It feels really good," he said.
"Some people have lived there all that time, and haven't seen a pristine, clean beach, so to be able to deliver that was enormously rewarding."
Mr O'Brien said there was still more work to do before the beach returned to its natural state.
"We need to just have some patience for the beach to mature to realise all the benefits," he said.
"In the meantime, we need to assist nature over the next few years to timely move the seagrass on."
