M2 Motorway Upgrade, Sydney
The Hills M2 motorway underwent an upgrade by the M2 operator Transurban between January 2011 and August 2013. New lanes were added to the existing motorway to provide increased transport capacity on the Sydney Orbital and better connections to the city.
New ramps were built to improve connectivity and the tunnel was widened. New noise walls were also installed, bridges were widened and seven hectares of bushland were revegetated.
A new design approach in accordance with Roads and Maritime urban design policy needed thoughtful and innovative consideration. The project proved challenging as it was an alteration and addition to an existing piece of infrastructure. This created a need to minimise impacts on road users and the community during construction.
A fresh style was decided for the noise walls, tunnel, and shotcrete stabilisation to draw the eye away from the existing walls and shotcrete and to frame the surrounding bushland.
Orange noise walls with clean, neat lines promote the greenery of the corridor and draw the eye away from the older walls. Dark grey walls were used at the top of cuttings to blend into the shadows of the bushland.
A new curved portal, increased internal space and fresh white panels provide a more comfortable, safe and attractive tunnel experience.
The bridges are perhaps the most innovative pieces of work, cleverly utilising cables and tensioning systems to sustainably extend and reuse the existing structures rather than replace them.