However, council staff are warning the council's coffers will not be so flush by July 1 - the start of the next financial year - and the cost of any winter storm could yet soak up any remaining surplus.
A report to the last finance, strategy and development committee meeting showed the council's operating surplus had reached $8.3 million by February 28.
That included a better-than-expected result for the Waipori Fund, which grew by just over $7 million to $76.9 million, which was $4.9 million better than expected.
The cost of depreciation was also $3.2 million lower than expected, due in part to asset revaluations, the report showed.
However, committee chairman Cr Syd Brown told the Otago Daily Times the figures did not point to a large windfall for the council on July 1, as depreciation savings were an accounting gain and not available to spend.
Neither were greater-than-expected Waipori Fund returns, as the council budgeted for an expected dividend each year and ploughed any other gains back into the fund's capital, he said.
''It's the value in the book, but it's not value until you've got it in the bank.''
The good result this year meant the fund had largely recovered after several years of larger withdrawals and bad financial results that had together eroded the fund's value, he said.
That meant a gap of about $6 million between where the fund's capital base was - and where it should be - had reduced to about $1 million, he said.
However, the size of any cash surplus was not yet known, although council staff were expected to present more detailed figures to the committee next month, Cr Brown said.
''The cash surplus figure has not been identified yet, and that's why I don't want [staff] to be putting a figure out there that is wet finger in the air.''
Council financial controller Maree Clarke told the committee the Waipori gains, and other variances, would ''mop up quite a bit'' of any surplus.
''We have to be very careful in interpreting the results.
''Any shocks, like a significant weather event ... could very easily mop up any surplus that there may be at the end of the year,'' she said.
