Balclutha residents have been without a pool since February last year when ongoing issues with the old boiler caused the pool to close.
Dunedin-based company Lund South Ltd won the $3.5 million contract for the Balclutha pool upgrade.
The upgrade includes a therapeutic pool and a bulkhead that will allow for the main pool to be shortened to 25m for competitive swimming and to separate the main pool from a new learners' area after a community fundraising drive.
The upgraded Balclutha pool was initially expected to reopen in January but weather conditions, delays in removing and replacing the roof and the incorrect tiles arriving from Italy meant the opening date was pushed back several times.
The commissioning of the new boiler is under way, and contractors have installed a two-tonne bulkhead in the main pool, allowing it to be split into a standard competition length 25m lap pool and smaller family or learners' pool, bringing it into line with most other pools around New Zealand.
The main pool took three and a-half days to fill, with an estimated 660,000 litres filling it.
Clutha District Council corporate services manager Alan Dickson said the pool was expected to reopen by the end of the month.
The upgrade includes:
Replacement of the old asbestos roof and walls.
New layout of learners' pool to provide safer area for toddlers with a shallower beach pool.
Family-friendly changing rooms.
Renewal of the heating and ventilation system.
Improved pool entrance.