The development of a new bridge over Perth's Helena River has been put on hold after traditional owners expressed concern over heritage impacts.
West Australian Transport Minister Rita Saffioti has asked Main Roads to discuss a potential redesign of the proposed Lloyd Street bridge with local Aboriginal representatives.
The talks will form part of a mediation process under section 10 of the federal Aboriginal and Torres Strait Islander Heritage Protection Act.
Federal Environment Minister Sussan Ley in March received an application from 12 traditional owners to reassess the $40 million project under commonwealth heritage legislation.
The bridge is jointly funded by the state and federal governments and will create a new southern entry to Midland, providing improved access to nearby amenities.
Traditional owners say the current bridge design will disrupt the flow of the Helena River, a registered Aboriginal heritage site considered sacred to the Noongar people.
The floodplain is considered the mythological site of the Wagyl, the Noongar creation spirit.
A proposed new alignment would move the bridge farther west to a narrower crossing, resulting in less imposition on native vegetation, nearby wetlands and the floodplain.
The reassessment represents a rare win for local traditional owners whose heritage concerns have frequently been overruled when it comes to major projects.
"As the local traditional owners and groups have suggested the new proposal, I am happy for us to examine this and see how it may work," Ms Saffioti said on Thursday.
"We took on this project on behalf of the City of Swan, and we will continue to work to make this project happen.
"While we undertake these discussions, the project will be placed on hold. Discussions with the contractors are under way."
The site also contains a rock shelter, although survey reports indicate it is not considered archaeologically significant.
Aboriginal representatives who participated in heritage surveys for the project in 2020 said they opposed the project.
But a survey report seen by AAP indicates they accepted the bridge was likely to be built because it was important to the state's economy.
It is understood participants were shown different design options but initially received little detail about the impact of the development.
Approval to disturb the site was granted under Section 18 of WA's Aboriginal Heritage Act last year.