The Council Customer Service Office and Library on Queen Street in St Marys are closed, due to flooding.
Penrith Mayor John Thain said the damage is significant and will take some time to be repaired.
“Unfortunately a good portion of the building was damaged, along with the Library collection and equipment inside,” Cr Thain said.
“It’s a devastating thing for this to happen, and a blow to the community who use this facility, especially at such a busy time of year.
“But I am pleased to say that Council staff have responded quickly and repairs are already underway.”
Council hopes to reopen the Customer Service Office and Library at St Marys, with limited services, by the middle of January.
The Civic Centre customer service counter and Library at Penrith remain open as normal, and the Library opening hours at the St Clair branch have been extended, to provide additional services while St Marys is closed for repairs.
For more information about Council Services, please call 4732 7777.