Bunkers Hill works have been extended due to unexpected utility connections.
As a result, improvement works will carry on until mid-November.
To allow the work to continue safely, daytime temporary traffic lights will remain in place Monday to Friday.
In addition, from Monday, October 29 to Wednesday, November 14, Bunkers Hill will be closed to traffic from 7pm to 6am, Monday to Friday, for resurfacing.
During the night-time closures on Bunkers Hill, traffic will be diverted via Ruskin Avenue, Nettleham Road and the A158. Access to Hawthorn Road will be via Kennel Lane.
Those wanting to access Hawthorn Road during the night-time road closures are asked to follow the main diversion before taking the A158 to Kennel Lane to Hawthorn Road.
The improvements have been funded by the county council, Environment Agency and Anglian Water.
Councillor Richard Davies, Executive Member for Highways, said: “While carrying out the drainage improvements, we’ve discovered that some of the underground utilities didn’t follow the path as advised by the utility companies.
“As a result, we’ve had to adapt our drainage plans, which has put us behind schedule.
“And although we’ve brought in extra staff, we’re now expecting to be on site until mid-November.
“We apologise for any inconvenience caused, but these improvements will reduce the chances of future flooding, so it will be worth it in the long run.”