The McGowan Government has been pushing Rottnest Island hard as a WA tourist destination and it is paying dividends.

Almost 770,000 people visited Rottnest in 2018, a 15 per cent year-on-year increase in numbers.

The visitor growth is so rapid, it's fast closing in on the target set just five years ago of achieving 800,000 annual visitors by 2034.

Meeting that benchmark 15 years early may be a financial success, but is the island's infrastructure and natural environment ready to receive that many visitors so soon?

Quokka selfies spearhead marketing blitz

Rottnest Island has been a key plank in Tourism WA's two-year action plan and the marketing blitz has been hard to ignore

It kicked off with a visit by tennis star Roger Federer in late 2017, which proved a marketing ace.

Roger Federer's quokka selfie in December 2017 attracted international attention to the island. ( Instagram: Roger Federer )

Federer's #quokkaselfie Instagram post generated half a million likes and made headlines around the world.

Since then, Tourism Minister Paul Papalia has made more than 20 media statements about the island.

A new ferry operator has been added, ferry tickets have been discounted, new businesses and recreational activities were added, and there have even been fishing clinics with a football star.

But how many tourist ventures, and tourists, can Rottnest Island accommodate without sacrificing the environment of this class-A reserve?

This question is especially relevant when it's Rottnest's clean and relatively unspoilt surroundings that are the biggest tourist drawcard.

Numbers of tourists to Rottnest Island have jumped in recent years. ( ABC News: Elicia Kennedy )

Mr Papalia said the State Government was considering a new management plan drawn up by the Rottnest Island Authority (RIA), which will also be put out for public comment.

"It's around comprehensive infrastructure demands for future and proposals for meeting these demands," he said.

"They [the RIA] are anticipating growth and ensuring we are able to deal with that."

Plan for a sustainable island

Over the past decade Rottnest, an island not connected to mainland water or power, has made major advances in environmental sustainability.

Last year the RIA released its first Sustainability Action Plan (2018–2024) — a set of targets it hopes will help protect the island's environment and cultural heritage as visitor numbers grow.

The report however references annual visitor numbers of 650,000, projected to grow to 800,000 in 12-15 years.

At current rates, it will take just a 4 per cent growth in visitor numbers to surpass that forecast.

A total of 800,000 visitors is predicted to raise the amount of rubbish generated to 1,615 tonnes, a 36 per cent increase on the amount generated in 2015–16.

Rottnest Island is becoming an increasingly sustainable operation. ( Supplied: Rottnest Island Authority )

It will also place greater demands on water sources, currently supplied by a desalination plant and recently upgraded wastewater treatment plant.

The year 2017 was the first time the island generated enough water to avoid pumping groundwater from the Wadjemup aquifer, which supports the island's lakes.

Despite then prime minister Tony Abbott's criticism of its "ugly" wind turbine, 30 per cent of the island's energy needs is now generated by wind power.

For the past 12 months about 45 per cent of the island's power has been generated by renewable sources, including a newly installed solar panel plant. The remainder is met by diesel powered generators.

WA Tourism Minister Paul Papalia has heavily promoted Rottnest Island. ( ABC News: Elicia Kennedy )

Mr Papalia said it was possible the RIA would propose a visitor capacity limit in the future.

"Everything done here complies with the obligations of one of the best governance regimes in the world," he said. "That is a good thing people can be comfortable about."

New accommodation 30 years in the making

Two new developments on Rottnest will not only increase visitor numbers, but also add to the pressure on this infrastructure.

On March 1, the first new accommodation offering in 30 years will open for business.

Visitors to Rottnest will soon be able to stay in premium "glamping" accommodation. ( ABC News: West Matteeussen )

Under a 20-year lease arrangement, 83 "glamping" eco-tents have been built on the northern side of the island, at Pinky's Beach.

The RIA is hoping the new accommodation dampens criticism that the island's self-contained units are expensive and at times difficult to book — housing in peak periods needs to be booked 18 months in advance.

It proclaims the 2.8-hectare development — which includes a pool, restaurant and bar — will be a "game changer".

Premium tents are the drawcard for the new Pinky's Beach eco-resort. ( ABC News: Elicia Kennedy )

Discovery Rottnest Island general manager Andy Cleverley said bookings were already looking strong.

"We are looking at around 28,000 guests per annum", he said.

But the biggest change to the island will arrive in 2020 when Hotel Rottnest — previously called the Quokka Arms — receives a $40 million redevelopment.

Its existing 18 rooms will make way for an 80-room resort with four pools, a restaurant and function centre.

"Most of the growth in [visitor] numbers is in day trippers," Mr Papalia said.

"I would like to contribute to getting more of them to stay overnight and staying for longer."

The hotel's development plans state it expects its water requirements will rise by 185 per cent and its energy needs will double.

Building will begin in May and is expected to be complete by the end of 2020.