Problem to be addressed
The Cockburn Central area is projected to experience high population growth, with the number of people living in the City of Cockburn forecast to reach 170,000 by 2031, a 60% increase from 2016. Ongoing development and the rapid population growth in the City of Cockburn is significantly increasing the volume of traffic travelling to and through the area.
The Armadale Road / Beeliar Drive interchange is experiencing severe congestion and traffic volumes are growing through the Midgegooroo Avenue / Beeliar Drive intersection. Safety is also a significant challenge, with Armadale Road between Cockburn and Armadale ranked by RAC as the state’s sixth riskiest road.
Without intervention, the additional pressure from population growth is expected to worsen travel outcomes, increase safety risks, and may affect development plans within the region.
The Armadale Road bridge proposal includes construction of a bridge over the Kwinana Freeway, with grade separated intersections between Armadale Road, and Solomon and Tapper Roads.
Two lanes in each direction for free flowing regional traffic will be constructed from west of the Armadale Road / Solomon Road intersection to east of the Armadale Road / Tapper Road intersection.
The project also includes:
- North-facing on/off ramps and two lane collector distributor roads on both sides of the Kwinana Freeway from Berrigan Drive to Armadale Road.
- Modifications to the existing Armadale Road / Ghostgum Avenue signalised intersection.
- Modifications to the existing North Lake Road / Midgegooroo Avenue signalised intersection.
- Two lane collector distributor roads adjacent to the regional traffic lanes between Armadale Road / Solomon Road intersection and the Armadale Road / Tapper Road intersection.
Economic, social and environmental value
Benefits of the project include travel time savings, vehicle operating cost savings and accident cost savings.
The proponent’s stated benefit-cost ratio is 3.0, with a net present value of $413 million (7% real discount rate).