Combined with a sewer main replacement and new traffic lights at the nearby Hanson-John Street intersection, we expect it to be completed by the end of November.
The Council's Infrastructure Director, Stavros Michael, says the work is an important project for Newtown - and for the city.
"As well as improving traffic flow through this intersection, the upgrade will improve the area for residents, business owners and shoppers. We also have to manage the expected increase in traffic from the new supermarket, and make sure pedestrians have safe places to cross the road."
Around 100 metres of the western side of Adelaide Road - immediately to the north of John Street - is being widened and realigned to create an extra southbound lane for cars heading straight up Adelaide Road, and two left-turning lanes into Riddiford Street.
Vehicles turning right into John Street will have their own lane as they do now.
The road widening is taking around three metres off the Zip Plumbing car park and a retaining wall will be built along the front. At the nearby Loafers Lodge, the ground floor of this building will be moved back to allow the footpath to pass through a colonnade, with the footpath separated from the road by columns.
On all approaches to the John Street intersection there will be upgraded traffic lights, street lights, footpaths, kerbs and gutters. Trees will also be planted on both sides of Adelaide Road. A new median island will be constructed near the intersection with Hospital Road.
Some electricity and telecommunications services - along the eastern side of Adelaide Road and Riddiford Street - are scheduled to be moved underground. Old wooden trolley bus poles will be replaced by steel poles.
From September, we'll slightly widen Adelaide Road by the new supermarket site to create a right-turning lane into the car park, and we'll landscape the southern corner of Adelaide Road and Riddiford Street.
We will also take the opportunity to replace a section of sewer main in Adelaide Road from Drummond Street along to John Street.
Final road resurfacing will be done when the sewer main and the supermarket are completed, with road markings to include places for cyclists to wait at the traffic lights.