New Darlington underpass? (A total guess).
New Darlington underpass, keep with the theme.
Along the 'Torrens to Torrens" road works?
Yes, along that stretch somewhere.
Umm.. Port Rd intersection?
I haven't been through there for a while @-|
Much closer but not exactly right, try for a structure that's so new it doesn't show up on google earth.
In the foreground might be a train track. So perhaps where the railway line is currently being 'undergrounded', at a point where resurfacing to normal ground level.
rossmg, the replies are getting messed up but I am somewhat to the right of and down from the origin of your purple arrow, right under the rail bridge next to the easternmost pylons. Andrew is most correct.