Rothbury swimming pool is closing for a week as part of a £1million county-wide investment programme.
Active Northumberland and Northumberland County Council are upgrading six pools across the county.
The work will involve the refurbishment, repair or replacement of the swimming pool operating plant, replacing it with more energy efficient and environmentally friendly equipment.
Rothbury is the first pool to have the work carried out.
It will be closed temporarily, from February 8, for one week.
The gym and fitness area will remain open as normal.
The pools at Willowburn Sports and Leisure Centre in Alnwick; Wentworth Leisure Centre in Hexham; Prudhoe Waterworld; Blyth Sports Centre; and Concordia in Cramlington will also have the improvement work.
Mark Tweedie, chief executive of Active Northumberland, the charitable trust that delivers leisure services for the county, said: “It’s really important to keep our facilities in good repair so we are investing to make much needed repairs and upgrades.
“Unfortunately the work required cannot be safely carried out while the pools are open, so we have chosen to schedule the work at the quietest time of the year for our pools to minimise disruption. We’d like to thank our swimmers for bearing with us and we apologise for any inconvenience caused.”
The county council has funded the major £1 million investment.
Coun Cath Homer, cabinet member with responsibility for leisure said: “ Our swimming pools are a really important part of the local community, but they are very costly to run with a big mechanical operation taking place behind the scenes to keep the water warm and clean.
“The work that is being carried out to upgrade the swimming pool plant will ultimately make the pools far more energy and cost efficient to operate.”