In 2011, the City approved a three-stage $1.91 million makeover for the park and museum, which would include new interpretive signage, upgrades to park furniture, the playground, lighting and the anchor blocks, alterations to the entrance to the park, and creation of three walking trails.
Each stage is proposed to take 12 months, with completion by 2014.
Stage one of the project was completed in time for the centenary celebrations last September, however stage 2 works need an extra $150,000 to go ahead as planned.
At the council meeting last week, a City officer presented a report to councillors recommending approval of extra funding for the project. He said costings had exceeded the original pricing for some works, including removal of render and paint to put it back to its original state, and interpretive sign work.
The budget had a shortfall of $143,000 for heritage building works and $120,000 for interpretive signage.
However, reallocating funds around meant the extra funding needed was $151,000 for stage 2 of the works.
Council will decide whether to approve the additional funding from the Community Facilities Reserve.