The fig has been looking a bit under the weather lately, prompting concerns the new $10.5 million Thirroul District Community Centre and Library has affected its health.

But the council's manager of community, cultural and library services, Jenny Thompson, said despite its discoloured leaves, the tree was still healthy.

"Council employed a consultant arborist prior to the construction of the Thirroul District Community Centre and Library to care for the fig tree," she said.

"We also built an on-demand irrigation system on site to ensure the tree always has the moisture it requires.

"The arborist inspects the fig tree quarterly and provides advice on its care and condition.

"The last report showed there are no indications of structural failure and recommended we administer another dose of slow-release fertiliser for the tree.

"We've just fed the tree with a spring dose of fertiliser and thanks to a recent spot of rain the tree is showing lots of new growth."

The tree is believed to be bigger than the Moreton Bay fig tree that gave Figtree its name.

The western suburbs giant had to be cut down in 1996 because of disease.

A cutting from the 200-year-old tree was replanted in 1998.

The fig tree was once at the junction of a track (now O'Briens Rd) that led to Sydney, developed in 1821 by Cornelius O'Brien.