Onchan-based CCJ Group Ltd will reconstruct a section of the street on either side of the new raised crossing point at the junction of Duke Street.
The works on the crossing started on October 3.
The reconstruction work means that the road will be closed from Sunday, March 19, to Sunday, April 2.
The Department of Infrastructure says that no pedestrian access to businesses will be affected as both sides of the path will remain open.
All traffic coming down Prospect Hill, including buses, will be diverted along Athol Street and vehicles using Ridgeway Street will be able to exit only up Prospect Hill.
Traffic from Thomas Street (Market Street and Drumgold Street and M&S car park) will also be diverted towards Prospect Hill, against the current one-way system.
There will be no access to Victoria Street from Thomas Street.
Cabs will pick up outside Conister Bank during the works.
After the work on the crossing is completed, all of Victoria Street will be resurfaced.
That work will start from April 19 and go on until May 3, when the road will be closed between April 19 and 26 from 6.30pm until 6.30am.
During the resurfacing, the road will remain open during the day, with traffic flowing normally from Prospect Hill towards Loch Promenade, albeit with a temporary road surface.
The third phase of the project will be the resurfacing of the lower half of Victoria Street.
A DoI spokesperson said: ‘The lower half is sufficiently wide to allow resurfacing to take place in live traffic, with work being undertaken during normal hours.’
All parking, bus stops and loading areas will be suspended for the duration of these works.
A crowd barrier will protect the public and there will be no disruption to pedestrians.
Cars using the road will maintain a single lane of traffic at all times.
Bus Vannin will be releasing information about temporary bus stops to replace those affected by the roadworks.