Westmeath County Council has provided an update on the works.
The Athlone Lock will be closed be closed for maintenance works later next week.
The lock will be closed to boat traffic on Wednesday 16th, Thursday 17th and Friday 18th February 2022.
The closure is in order to facilitate the relocation the hydraulic and electrical services as part of the flood relief works.
Waterways Irelands has issued an advisory to all masters of vessels and water users, thanking them for their co-operation.
That comes as Westmeath County Council this week confirmed that Athlone's flood defence works will be substantially complete by the end of this year.
Responding to a question from local Fine Gael councillor John Dolan, the council officials said 85% of the work is now complete.
It added that work in some areas may not be finished until 2023.