Traditional owners with the Department of Environment, Land, Water and Planning mapped the site using light detection and ranging technology (LiDAR) late last year.

Gunditj Mirring Traditional Owners Aboriginal Corporation's Denis Rose said the maps had since revealed a new 115-metre long channel on Aboriginal land at Lake Condah.

"We hadn't walked through there or hadn't noticed it in some fairly thick vegetation," Mr Rose said.

"This LiDAR technology, strips the vegetation off the images and gets to the ground surface."

The technology also showed another channel in the Budj Bim National Park, thought to only be about 40 metres long, in fact reaching 160 metres.

The two channels are now among the longest in the area, which also includes weirs and dams. Once used to catch fish, the aquaculture system is the world's oldest, carbon dated to 6600 years old.

"It keeps confirming that this aquaculture system that was engineered by our Gunditjmara ancestors is much more extensive than we previously thought," Mr Rose said.

"Now we have this technology it's increasing the size."

There were up to 80 components of the aquaculture system but Mr Rose said that number was growing.

The maps have also identified about a dozen sites that could be the remains of stone houses while the technology is helping to confirm locations of a further 60 stone houses.

"It will give us confidence that some areas have cultural heritage sites and that's where we will put our management," Mr Rose said.

Deputy Secretary Local Infrastructure Terry Garwood said the state government had granted full ownership of the mapping data and spatial information to the Gunditj Mirring Traditional Owner Aboriginal Corporation once captured.

"This partnership - and investment - is one of the ways we are working to enable Aboriginal talent-building, leadership and decision-making, as well as data sovereignty, as part of the Victorian Government's commitment to progressing Aboriginal self-determination," Mr Garwood said.

It follows a fire in Budj Bim national park last year that uncovered two lost aquaculture systems and nine stone houses.

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