Kiama Leisure Centre has received a $120,000 boost thanks to a donation from a long-term member of the centre, who wants to remain anonymous.
Kiama Mayor Brian Petschler said the member, who was not in the best of health, "wanted to give back to the centre which has been a big part of his life for many years".
Cr Petschler said while not holding Kiama Municipal Council to how the money should be spent, some suggestions were offered by the donor.
"He did stipulate that the money was not to be used for maintenance or repairs," he said.
Cr Petschler said the centre's management was now considering the best use of the donation.
"In the normal course of events it would be appropriate to invite the person to a civic function to formally recognise his generosity ... however given his desire to remain anonymous, that will not be possible," Cr Petschler said.
Kiama Leisure Centre was badly damaged by a tornado that hit Kiama on February 24, 2013, forcing the closure of the centre for six months while it was repaired and renovated.
About $2 million worth of improvements were made, some funded through insurance, while other improvements were in a planned upgrade funded by Kiama Council.