The spa at Willowburn Sports and Leisure Centre has suffered from a lack of users over the last year and owners North Country Leisure (NCL) have now taken the decision to close it.
However, the space will be used to build a climbing wall for all
ages and abilities, with the hope of enticing more people to the centre and providing a facility that is more accessible for members.
John Maude, chief executive of NCL, said: "We have been concerned for some time about the high cost and low use of the spa (sauna and steam room) area at the centre.
"In spite of refurbishment and marketing campaigns, in the last 12 months there have been only 1,167 recorded visits to the area, just over three per day.
"The spa costs £15,000 a year in direct running costs, mainly energy costs, which have risen dramatically in recent years.
"Whilst North Country Leisure, the charity which manages the site, does receive council subsidy towards running costs, it is very hard to justify a subsidy of nearly £13 per use for the spa.
"We have therefore been looking at alternative uses for the space and have taken some specialist advice.
He added: "The current spa will close on Saturday, October 31, when we will begin work to convert the area into a bouldering wall; a climbing facility aimed at all ages and abilities, which we believe is an extremely popular development that people of all ages can enjoy.
"We wrote directly to 3,299 customers explaining this in July (as well as providing information at Willowburn) and received only 11 complaints about the proposal to close the spa.
"Naturally, we have sympathy with existing customers who use the area regularly, but feel that we cannot justify keeping it open, especially when there is an exciting scheme to develop the space.
"We will continue to keep customers informed throughout the developments."
Kate Murdoch, assistant manager at Willowburn said: "What people don't necessarily realise is that this area is fantastic for climbing."
She added that the climbing wall will be the only facility of its kind between Newcastle and Edinburgh.