An expansion of the Oasis Springs water world at Australia’s Gumbuya World theme park will almost double the size of the waterpark it has announced.

Six new waterslides, comprising two “monster” twister slides and a four-lane rally race slide, and a new family wave pool, are to be installed at the attraction, which is located close to Melbourne, Victoria. Already on site in Oasis Springs are Typhoon Island – an "aquatic jungle gym" – a 300m (984ft) Lazy River, epic water slides, heated rock pools and surfing at Surf’s Up.

The company said it hopes the newly enlarged Oasis Springs will be ready around the time of the Australian springtime, which is between the start of September and the end of November 2019.

Major developments are planned for the entire Gumbuya World site, with a target of attracting a million visitors per year by 2022. Alongside Oasis Springs, the theme park includes three additional “worlds”: Oz Adventure; Outback Explorers; and Wildlife Trail.

Over the next three years, the theme park said it will offer 50 new attractions, as well as a range of onsite accommodation, new cafes, shops, a chocolate factory and a microbrewery. It will also include indigenous, dinosaur and woolshed precincts for educational programmes.