Lake resort for Rottnest

New look: The Rottnest Lodge revamp. Illustration: Supplied

The Rottnest Lodge will be virtually rebuilt on nearly 5ha of land around one of the island's salt lakes as part of a $20 million plan that will include 80 units, a restaurant and bar, gymnasium, spa and therapy pool, and open-air cinema.

Work on the project is expected to begin within a year after the signing of a heads of agreement on Thursday.

The new 4½-star resort will be the first new accommodation on the island in more than 30 years.

It will also be the biggest infrastructure investment by the private sector in the island's history.

British-born developer John Spence's Karma Royal Group, the owner of the Lodge, has agreed to a 50-year lease for a parcel of land that winds around Garden Lake, between the existing Lodge and the island's golf course.

It intends to build the island's best quality accommodation.

In exchange, Karma will stop using the Quod - the former Aboriginal jail where about 300 prisoners died - for tourist accommodation. While basic plans for the resort have been completed, Mr Spence has asked 14 postgraduate students from the University of California, where he is a visiting fellow this year, to design the new accommodation units.

He wants them to be comfortable and "funky", but within the environmental and heritage constraints of the island.

Interested parties would be consulted "because I want the people of Perth to be proud of what we create".

Mr Spence said room rates at the resort could be up to 10 per cent higher than existing charges, which range from about $220 to $360 during peak periods.

Negotiations over the future of the Quod have been continuing since Karma took over the troubled Lodge from Bankwest in 2011.

Bankwest had been a reluctant operator of the Lodge for 20 years after the collapse of Alan Bond's Dallhold Investments.

Final agreement culminated in Thursday's signing by Mr Spence and Rottnest Island Authority chairman John Driscoll.

The only existing Lodge units to be incorporated in the plan will be about 20 relatively new lakeside apartments.

The new units will be largely prefabricated.

Older Lodge units could be transferred to the RIA or used as staff accommodation.

"I am extremely exhilarated that, after many years of work, this agreement has been solidified," Mr Spence, a former Tourism WA board member, said.

"WA is very important to me, both personally and professionally.

"Our vision has been designed to honour every aspect of the stark natural beauty and history of Rottnest Island and will garner global media and industry attention to WA.

"It has long been my dream to create a world-class resort on the island complete with a wide array of amenities and facilities and to share this with both WA and a global audience of sophisticated leisure travellers who appreciate its history and stunning vistas."

Tourism Minister Kim Hames said Rottnest visitors would welcome news that the development would proceed with environmental sustainability, design and quality in mind.

Most of the facilities will be open to all island visitors, not just resort guests.

These include the restaurant and bar, the treatment rooms and the kids' club.

Mr Spence said the company would also look at buying a boat for guests to charter.

And it was keen to be involved in consultations over RIA plans to build a marina and adjacent accommodation near the Army Jetty in Thomson Bay.

The Karma Royal Group was recently announced as naming rights sponsor of the Rottnest Channel Swim.