The Department of Planning Transport and infrastructure (DPTI) engaged Grieve Gillett Architects (GGA) with Aspect Studios to develop an urban design framework to cover the entire corridor from Gawler in the north to Old Noarlunga in the south.

The South Australian 30 Year Strategic Plan identified the north south corridor upgrade as a key strategic initiative. Five component parts of the upgrade have been delivered - the Northern Expressway, South Road Superway, Gallipoli Underpass at ANZAC Highway, Tram over South Road and the Southern Expressway duplication. All of these projects had been delivered in the absence of an overarching urban design framework (UDF), as a result creating a fractured and disparate collection of elements and forms along the corridor.

The engagement also included preparation of reference designs for Torrens to Torrens (T2T) and Darlington Interchange projects. The UDF covered sections of the corridor already delivered with a key purpose of integrating the disparate language of the existing projects with new projects about to be commenced. GGA and Aspect delivered the UDF and T2T reference design in ten weeks to allow the commencement of the contractor bidding process of the Torrens to Torrens project and the competitive alliance.