The pool had been unused because it needed the new liner. The school's board of trustees funded a new one under its annual property programme.
The pool will be open to the National Park community next week. It will also be used for youth water polo and a number of other activities.
Miss Welburn told the Ruapehu Bulletin that "back in April last year, the pool was used as a storage place for junk, there were leaks in the roof, the garden was a jungle and the building facilities were in a state of disrepair. The pool, which had once been at the heart of the community, was in need of some serious TLC.
"It has been a fascinating journey with lots of people coming to tell us about their experiences as children learning to swim there," she said.
It's possible the school now has the country's top pool. At an altitude of 825m it's up there.