Long-term projections had debt at July 1 this year reach nearly $355 million - $25 million more the figure in the 2016-17 draft Annual Plan.
However the $63.8 million debt increase in 2016-17 was $8.5 million or 15 per cent more than projected in the long-term plan.
The vital ratio of debt to revenue was estimated to reach 205 per cent, or 12 per cent less than the figure in the long-term plan.
This means the council's debt will be more than double annual revenue of $188.4 million at June 30 next year.
Debt to revenue ratios were important financial indicators that impacted on interest rates the council paid on its loans. The council's self-imposed ceiling was 250 per cent.