New signals are to be installed at the junction of Eastgate and Carre Street in Sleaford later this month.
Lincolnshire County Council highways officials say the existing equipment is reaching the end of its life and needs to be replaced, with work beginning on Sunday July 21.
The project is expected to take four weeks to complete, although timescales will depend on the weather.
Although the road will remain open to traffic for the majority of the project, temporary three-way traffic lights will need to be put in place, along with two temporary pedestrian crossings, says the council.
However, two day-long road closures will be required on Eastgate heading East to allow the traffic island to be removed. This work will be carried out over two Sundays to minimise disruption. The first will be Sunday July 21 with the second being Sunday July 28 (if required).
During these brief closures, traffic will be diverted via East Road, the A17 and B1518 Lincoln Road/North Gate.
Anthony Gent, principal engineer for traffic signals, said: “The new signals will be easier to maintain and much more energy efficient, saving on annual running costs.
“There will be some disruption while the work is carried out, and we apologise for any inconvenience caused in advance.
“We’d advise motorists to leave additional time for their journeys.”