The damaged 'Bedford Bridge' in Quadring Eaudike will be replaced.
The Work will start on Monday 4 October and is expected to last nine weeks.
The northern side of the bridge partially collapsed in late 2019 and was temporarily repaired. Now the structure is to be fully replaced with a new wider bridge with concrete parapets.
Water Gate will have to be closed in Quadring Eaudike between Sarah Gate and Wood Lane whilst work takes place. A local diversion route will take traffic through Quadring and Gosberton.
Access to the properties immediately adjacent to the work will be maintained, but there will be no route over the drain as the bridge is to be completely replaced.
Cllr Richard Davies, executive member for highways at Lincolnshire County Council, said:
"We carried out temporary repairs last year to keep this bridge safe, but it has narrow verges and low sides, so now it's time to replace it and bring it right up to standard.
"The new bridge will have concrete parapets to make it safer. I thank local residents for bearing with us whilst we carry out this work."
Keep up to date with road improvements in your area by visiting www.lincolnshire.gov.uk/worksprogrammes.