Australia’s Dreamworld will reopen to the public on 10 December following an accident in October that resulted in the deaths of four people.

Two men and two women were killed on the park’s Thunder River Rapids ride on 25 October when the conveyor belt system returning them to the station malfunctioned, causing their raft to be flipped upside down.

In a statement, Ardent Leisure – the Gold Coast park’s owners – said that all of sister park Whitewater World’s rides would be opened immediately, while those at Dreamworld would “progressively open as they are signed off as part of the safety review process”.

Additionally, Ardent said that its theme park division would suffer operating losses of around AU$4m (US$3m, €2.8m, £2.4m) for the period of closure, and one-off costs of AU$1.6m (US$1.2m, €1.1m, £953,000) in relation to the accident. Ardent estimates the extended closure will cost the park will cost the operator around AU$10m (US$7.4m, €7m, £6m) overall in lost revenue.

Commenting on the park’s reopening, Dreamworld CEO Craig Davidson said four independent safety investigations would be conducted by 10 December.

The Queensland Workplace Health and Safety, last week issued seven improvement notices for Dreamworld and Whitewater World, including outdated protective equipment on the Flowrider and a faded “emergency stop” button on one of its waterslides.

During the incident, two of the people were thrown from the ride and the other two were reportedly trapped in the conveyor belt which takes riders back to the station. Water in the station area was drained by emergency services trying to rescue the people trapped by the conveyor belt. Six people were on the ride when it flipped over.

Ardent Leisure chief executive Deborah Thomas has said that the Thunder River Rapids will be permanently closed, out of respect to the victims and their families, with plans to create a memorial in its place.