The Bishop bridges on the A57 outside Lincoln before Burton Waters will undergo maintenance.
Lincolnshire County Council will carry out work on Bishop Bridge East and Bishop Bridge West on the A57 in the coming weeks.
The bridges, which carry the A57 over the Catchwater and Main drains, require essential maintenance in order to extend their life.
The works have been scheduled to take place over the school holidays to minimise disruption, from July 9 for six weeks until August 16.
Traffic will continue to be able to flow two-way throughout the works, although speed restrictions will be in place.
Richard Waters, Principal Engineer at Lincolnshire County Council, said: “These repairs are important and will considerably extend the life of these two bridges.
“We’ve planned to carry the work out over the summer holidays to limit disruption, although some delays are expected and I would advise motorists to allow extra time for their journey.
“On behalf of Lincolnshire County Council, I would like to apologise for any inconvenience these works may cause.”