Minor repairs will be carried out starting in early October.
The works will start on Monday 6 October for up to five days, which includes the time needed for repair and curing.
A series of phased 24-7 road closures on Conduit Lane, Market Place, and Narrow Westgate will be in place during these works, with only one leg closed at a time.
The signed diversion route for the Conduit Lane closure will be via Union Street / North Street / Broad Street / Brownlow Street / Brook Street / Watergate.
The diversion route for the Narrow Westgate and Market Place closures will be via High Street / Wharf Road / Sankt Augustin Way / Dysart Road / Westgate.
Karen Cassar, assistant director for highways, said: “We always carry out tests to ensure newly-laid road surfacing, including stone setts, meets the high standards we expect.
“Unfortunately, some of the setts laid last year have delaminated, leading to them loosening and not meeting our stringent quality requirements. This isn’t unexpected, as stones can sometimes have weak spots or natural cracks that lead to small pieces breaking or chipping off. These weak spots, or failure planes, are one of the risks we’d expect when using natural stone.
“Despite this being a risk we expected could occur, the supplier of the setts will be appointing a contractor to repair these sections of the square at their own cost.”
While on-site, the local highways team (working with a designated heritage team) will also be carrying out maintenance works to the footpath near St Wulfram's Church, including re-laying the slabs and improving the surface of the existing paving to enhance safety and appearance. These works will begin on are scheduled to begin on Monday 15 September for up to three weeks.
The local highways team will then move to Westgate and Welby Street to carry out repairs to the footway and reinstate missing bollards and street furniture. This work will be undertaken from Monday 6 October until the end of the month and will involve the temporary suspension of some of the parking bays along Westgate so the works can be undertaken safely.
For up-to-date information about this and other roadworks, visit www.lincolnshire.gov.uk/roadworks.