Repairs are being made to sections of the £9 million flood defences in Malton and Norton in an attempt to reduce the risk of the wall leaking.
The move from the Environment Agency follows a review of the floods of November last year when heavy rain caused the River Derwent to rise to its highest levels since the flood defences were built at the turn of the century.
Although the river did not rise above the defences, the high levels caused some areas to leak.
Now Environment Agency contractors are starting work on the brick flood wall on the Corn Mill right bank, upstream of Railway Bridge, and the stone wall left back, directly downstream of County Bridge.
At the Corn Mill, contractors will break out and rebuild the section of brick wall that has cracked, improve the expansion joints to minimise cracking in the future, re-point as necessary and re-bed any loose coping stones.
Downstream of County Bridge, vegetation will be cleared and a stone flood wall will be re-pointed.
For the work to be done safely, one lane of Norton Road will be closed for around four weeks - depending on river levels and weather conditions.
Paul Knight, project manager at the Environment Agency, said: “We have carefully planned the work to minimise any disruption to residents and would like to thank them for their patience and support whilst we are doing the repairs. This work is necessary and will help to reduce any future disruption during a flood.”
The road lane closest to the footpath will be closed for the duration of the work to allow the contractors to use the footpath as working space for scaffolding and for the re-pointing work.
Pedestrians will be diverted into the closed lane, meaning the road will employ a temporary one-way system.
The work is part of annual maintenance that officers carry out all year round.
The highest known floods in Malton and Norton have been in 1947, 1999 and 2000. The £9 million Malton, Norton and Old Malton flood alleviation scheme was built following the 2000 floods and was completed in July 2003. The defences provide protection to 311 local properties and businesses as well as helping to prevent disruption to the road and rail network.