The construction works to duplicate the expressway are well underway and involve many simultaneous activities and multiple work sites along the 18.5-kilometre project corridor.
The works will generally take place in the following order:
- relocation of utility services
- earthworks and drainage works
- construction of bridges and interchanges
- construction of the new road carriageway and ancillary work such as noise treatments, lighting, line marking and signage
Large D11 dozer used for rock breaking and other construction activities
In addition, controlled blasting is required along the escarpment between Seacombe Road and Majors Road to make way for the new carriageway, and roughly 170 service utilities are being relocated, protected or adjusted.
Some construction may be carried out at night to reduce the impact on road users and to complete these complex works as quickly as possible.
While every effort is being made to minimise disruptions for local residents and businesses, the construction involves heavy trucks and specialised equipment moving through the area, resulting in noise and dust and temporary changes to traffic conditions.
Measures to reduce the impacts include:
- establishment of access roads in the expressway corridor to maintain traffic movement on the local roads network
- dust management by planting on stockpiles, using water carts and utilising purpose-built access roads where possible
- advance notice of traffic changes and service interruptions to affected residents and businesses
- staging bridge closures to ensure that at least every second bridge remains open, offering motorists a convenient detour.
Most of the estimated two million tonnes of soil and rock excavated in the corridor are being stockpiled along the road and gradually will be re-used in construction and landscaping.
The local community is reminded to be aware of trucks and construction equipment entering the expressway at the following access points:
- Panalatinga on-ramp
- Smith Creek
- South of Sherriffs Road
- South of Flaxmill Road
- North of O’Sullivan Beach Road
- North of Christies Creek
- South of Christies Creek
- North of Flaxmill Road
- South of Perry Path
At the southern end of the Southern Expressway a new mound is being created from recycled materials to shield residents from the roadway and provide a lookout with views of the Mount Lofty foothills, Onkaparinga River and Gulf of St Vincent.
The approximately 500m wide and 9.5m high mound will be created from material leftover from the Expressway earthworks and terraced with stone excavated from the project site.
Native trees will be planted to create a landscape natural to the area and stormwater will be fed into an adjacent detention basin.
Pedestrians and cyclists will be encouraged to travel to the lookout using the new recreational path being built on the western side of the duplicated Expressway.
Panoramic view from eco-mound