Five new thermal pools and a 13.5m-high slide will be built in Hanmer Springs this year.
Hanmer Springs Thermal Pools and Spa's facilities will be extended at a cost of $4.5 million.
They lodged a resource consent application with the Hurunui District Council last year and announced yesterday that it had been granted.
The pools' general manager, Graeme Abbot, said they were rapt with the positive feedback and support they received.
There were no submissions opposing the application.
Hanmer Springs' Business Association acting chairperson Michael Malthus said pools were a huge drawcard for Hanmer Springs so the development would be a benefit to the whole village.
"Every time they have undertaken a major development, visitor numbers increase, which in turn provides considerable economic benefit to the whole village."
The five new thermal pools will sit among river boulder terraces and native gardens on what is currently a grassed area, while the slide will attach to the existing hydroslide tower.
Half of the energy required to run the pools and slide will come from a new 65-kilowatt heat transfer unit, making the new development more environmentally sustainable.
Construction is due to start in coming weeks.