The Victorian Civil and Administrative Tribunal this week rejected Yumbah Aquaculture's $60 million plan at Dutton Way, near Portland.

The plan, which was approved by Glenelg Shire Council and the Environment Protection Authority (EPA), was set aside by the tribunal after 27 days of hearings.

The tribunal ruled that the aquaculture facility presented "an imposing volume of built form across the landscape and within the vista from dwellings located on the escarpment".

"We conclude that this aquaculture facility would change the character of this rural living zone," the decision read.

"It seeks too much from its location and would result in landscape and visual amenity impacts that are not acceptable, therefore creating a conflict with the purposes of the zone."

The proposed facility would have been the size of 23 MCG playing areas and would have operated 24-hours-a-day.

Plans included a hatchery, a 200-tank nursery facility and large growing area covered by a shade cloth.

The tribunal started in February but was delayed due to the coronavirus pandemic.

Dutton Way resident and community spokesperson Tony Wright said the finding was about two years in the making.

"Our quite long and convoluted process has ended the way we believed it should have from the start," he said.

"We feel that our argument is vindicated. We don't feel triumphal or otherwise we just feel that our very simple argument was accepted - that being that this proposal of an industrial scale development right across the road from people's homes, in a seaside location that is essentially a long-settled village, was the wrong place."

Mr Wright stressed that the residents group was not opposed to Yumbah Aquaculture setting up a large abalone farm "in the right place".

"It was going to be the biggest onshore abalone farm in the southern hemisphere and very probably in the world," he said.

"We do hope they are still able to build something in an appropriate place."

Yumbah Aquaculture general manager Tim Rudge said he was "shocked and heartbroken".

"We've all worked so hard to get it this far so it is very disheartening," he said.

"We're also incredibly disappointed for the Portland community and the Victorian seafood industry.

"This was going to be the biggest investment in the industry in the history of Victorian seafood, there are more than 100 job that are potentially lost, as are the dreams and aspirations of young people that work here that want to stay in this region.

"The team here are all a bit flat to tell you the truth."

Mr Rudge said although the tribunal's findings were not favourable they were "confined to the visual amenity and landscape values only".

"They found no other inappropriate plans associated with the facility. Noise, odour, traffic and birds all got a big fat tick," he said.

"It's just the visual amenity (that was rejected) which is pleasing because we were scrutinised for months."

Mr Rudge said Yumbah remained committed to Dutton Way and the Portland community.

"We are currently just digesting and wondering what is next," he said.

"We have invested so much blood, sweat and money into this proposal, we haven't given up yet."

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