The works taking place on the N4-N15 roads on the Donegal side of Hughes Bridge in Sligo town are expected to be completed by July 2020.
The work involves upgrading 730 metres of the dual carriageway, and includes improvements to junctions and the traffic management system.
Details of the works were outlined at this month’s meeting in Sligo Town Hall of councillors from the Sligo Borough District.
Three lanes are to be provided in both directions between Hughes Bridge to just north of the junction for Rosses Point.
Upgrade works will be done on Markievicz Road, Duck Street and the Rosses Point Road.
The works will also include modifications to Salmon Point Recreation Area and the open space at the N15 and Rosses Point Road.
A masonry arch section of Rathquarter Bridge involving a culvert for Copper River will be repaired.
A remaining section of the Copper River culvert will be replaced and extended.
Retaining walls, earthworks, drainage and diversion of utilities such as Eir, eNet, ESB and Virgin are also part of the project.
There will also be new pavements, landscaping, new street lighting including LED lanterns, as well as enhanced footways and cycleways.
The work will include a sophisticated Urban Traffic Control System which, engineers say, will allow traffic lights along the route to be coordinated, to ‘talk to each other’ in real time.
The Urban Traffic Control System will involve 13 junctions, providing what the county council says will be state-of-the-art traffic signal technology that will improve traffic flows through the junctions.
Fibre-optic communications technology will feed into Sligo County Council’s ‘Smart City’ initiative.
The works are expected to be completed by July next year; meanwhile, traffic management arrangements will be in place for both vehicles and pedestrians.
There will also be diversions of N15 southbound traffic to allow nighttime works during the coming weeks..