Environmental impact managed on Mandurah Entrance Road

The $155 million Mandurah Entrance Road is currently under construction to provide a 6.5 kilometre, four lane dual carriageway link from the new Kwinana Freeway extension to Mandurah – one of Western Australia’s fastest growing Local Government Areas.

The Australian Government has committed $77.5 million to the project, as part of the Nation Building Program, and brought forward $16.5 million into 2008-09 as part of the Nation Building – Economic Stimulus Plan announced in December 2008 to accelerate the commencement of the new road by a year. The Western Australian Government is also providing $77.5 million for this project.

The road is being delivered by the Southern Gateway Alliance, comprising Leighton Contractors, WA Limestone and GHD in conjunction with Main Roads Western Australia.

The Alliance, which recently delivered the Kwinana Freeway extension and Forrest Highway, recognises the environmental challenges and constraints involved in road construction. As a result, they are committed to enhancing both the built and natural environment in the locality of the project, minimising the project’s impact and improving the local environment where possible.

As part of this commitment the Alliance recently adopted a number of initiatives to reduce the impact of the road clearing operations on local fauna.

Targeted rare fauna surveys were undertaken in preparation for the clearing and throughout the clearing process the environmental team undertook fauna searches and relocation with the assistance of a local specialist.

The team also used an elevated work platform to inspect tree hollows and remove nesting birds. If possums or other mammals were discovered, a trap was placed around the base of the tree overnight and the animals were later relocated. Inspections of the clearing line were also carried out, as well as relocation of fauna prior to construction activity.

The majority of the captured fauna was relocated to the nearby Marlee Reserve, which comprises 48 hectares of natural bushland, a boardwalk and informal walking trails. Bird eggs and chicks were sent to wildlife carers until they could be released.

The team has also been working with the University of Western Australia and the Department of Environment and Conservation as part of a study on changes in possum behaviour due to road construction, with the findings from this study likely to be of benefit to future road planning in the state.

Project Director Nick Combe said while it would not be possible to eliminate all of the impacts of construction on the community and environment, the Alliance was endeavouring to minimise these impacts and undertake the project in an environmentally sustainable manner.

“The extensive fauna relocation that was undertaken on this project is just one example of the many ways the Alliance is committed to minimising the project’s impact on the community and the environment,” Mr Combe said.

The Alliance continues to work closely with various stakeholders, including local environmental groups and the Conservation Council, and regularly meets with a Community Representative Group to ensure ongoing stakeholder involvement.

“We also aim to minimise our impact to the greatest extent possible by providing advance notice, effectively programming our works and implementing a number of on-site management plans,” Mr Combe said.

In addition to the fauna relocation works, the impact on the local environment was also lessened through a number of design modifications including steepened batters and additional retaining walls to reduce the clearing footprint.

“We managed to retain around 15 significant trees as a result of the design modifications, as well as pockets of native flora,” Mr Combe said.

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