M275 lane closures to resume after congestion problems
A new round of maintenance work on the M275 in Portsmouth is set to start with warnings of "significant delays".
The waterproofing project had to be postponed last month after the first phase caused "appalling" congestion.
The latest round of work starts on Monday with one lane of the northbound carriageway shut between 20:00 and 05:30 BST up until Friday morning.
Motorists have been asked to find alternative routes. Diversions may be enforced under extreme conditions.
Major congestion was caused in June when lane closures were put in place during peak times.
This has been avoided this time round, Portsmouth City Council's contractors Colas said.
Paul Ferroni, asset manager for Colas, said: "The work... is going to cause significant delays throughout Portsmouth but the essential maintenance work has to be done."
Waterproofing needs to be done about every 40 years to ensure bridges keep their structural strength.
A final phase for the M275's southbound carriageway is set to take place in the autumn.