The new roundabout at the A46 Dunholme and Welton junction is nearly ready, and will be fully open next month.
The project began in July and, subject to weather, will be complete and fully open to the public by the end of May.
As well as the roundabout, Horncastle Lane and northbound Lincoln Road will also reopen during the week commencing April 19.
Final preparation works will mean that five nights of road closures are needed to lay the final layer of road surfacing on the A46 between Deepdale Lane, Nettleham to Lincoln Road, Dunholme.
The closures will take place overnight between 7pm and 6am, starting from Tuesday, May 4.
The A46 will be closed from Deepdale Lane, Nettleham to Lincoln Road, Dunholme, with a diversion route via the A46 Nettleham roundabout / A15 Riseholme roundabout / A15-A1500 Showground roundabout / A15-A631 roundabout at Caenby Corner / either the A631 or A1103 back to the A46, and vice versa.
Lincoln Road, Welton will close from its junction with Honeyholes Lane to the new roundabout, with a diversion via Honeyholes Lane / right onto Ryland Road / right onto Lincoln Road Dunholme, which joins the main closure diversion on the A46 towards Lincoln.
Finally, Horncastle Lane will be closed from the A15 to the A46, with access at the A15 end. The diversion route will be via the A15-A1500 Showground roundabout / A15 Riseholme roundabout / A46 Nettleham roundabout, and vice versa.
During these closures, Heath Lane to Scothern will remain closed, with a right-turn ban and 24/7 temporary traffic lights on the A46 until the end of the project.
The full A46 Dunholme / Welton roundabout project has been part-funded by the £2 million allocated to Lincolnshire County Council by the Department of Transport.
The remaining funding has come from a combination of the council themselves and third party contributions.