An Australian-led project will create a groundbreaking sanctuary for sick and injured orangutans in Indonesia, with the aim of changing attitudes of the country's decision makers towards rainforest and animal conservation.

Preparation has begun on the orangutan haven following the securing of a 48-hectare site in rainforest near the city of Medan, on Sumatra. An initial batch of three orangutans will be placed in the sanctuary, which will feature a series of small islands separated by water. Orangutans, which are scared by the prospect of swimming, will be free to roam their individualised islands, which will feature trees, feeding platforms and problem-solving puzzles. It is hoped that further disabled orangutans will be able to join the initial trio once the haven is completed. Orangutans are endangered due to the loss of their rainforest habitat, which is cleared for the cultivation of crops such as palm oil. But they also risk catching diseases from humans and are regularly shot and imprisoned by people after wandering onto their properties, often in search of food. One of the three orangutans earmarked for the haven, Leuser, was shot 62 times with an air rifle, causing him to lose his sight. A second, Tila, carries the human strain of hepatitis B, while the third, Dek Nong, has lost the use of her limbs due to a chronic arthritic condition. None of these orangutans would be able to live in the wild and are currently kept in cages in a quarantine centre.

The Sumatran Orangutan Conservation Program, the group behind the sanctuary, has rescued 270 illegal pet orangutans over the past decade, releasing many of them back into the wild. Although there are only an estimated 6,600 orangutans left in Sumatra, criminal prosecutions for the illegal keeping or injuring of the flame-haired apes are extremely rare.

Jessica McKelson, former primate supervisor at Melbourne Zoo, is project managing the sanctuary while Green and Dale Associates, a Melbourne-based architecture firm, has designed the layout of the site. Two organisations from the UK – Jersey Zoo and the Orangutan Land Trust – are also assisting the project.

McKelson told Guardian Australia that a key component of the sanctuary was to radically shift the perceptions of influential Indonesians to help prevent further loss to orangutan habitat.

"We wanted to create a semi-wild setting for orangutans that can never be released but also create a wildlife conservation education centre that is unique for this region," she said.

"The target audience will be the middle class decision makers and palm oil plantation owners to show them how land can be used differently. The orangutans can be an ambassador species in a place where people can take their children and develop empathy and understanding of what actually happens in the field, away from the city."

The sanctuary's education centre will explain how orangutans come into conflict with humans, as well as showing how the illegal wildlife trade harms local populations of fruit bats and slow loris, which are trafficked and consumed in the erroneous belief they cure ailments such as asthma.

The centre, which aims to employ more than 100 local people, will also display sustainable farming practices.

"We want to work on a grassroots level to show that it's not helpful to clear an area that's a watershed for Medan for development," said McKelson. "But we also want to work at that investor level to increase understanding and education.

"We really want to encourage Indonesian citizens to get involved. We want them to make it theirs, rather than for it to be a big foreign project."

Stuart Green, principal of Green and Associates, said the sanctuary was designed to have a "bit of a story" to it.

"It's quite an ambitious project but one that certainly should be done," he said. "The location is this beautiful hidden valley but it is close to the city. The orangutans are being brought close to the town to present their case."

The sanctuary is embarking upon a fundraising drive to raise the $1m it needs to complete the centre via its Earth4Orangutans scheme.