Posted about an hour agoFri 29 Nov 2019, 6:12am
A short-term glamping eco-resort on Rottnest Island could become a test case for future beachfront developments, as the State Government weighs up whether to push back holiday cottages under threat from coastal erosion.
- Eco-tents at Pinky’s Beach were the first new Rottnest accommodation in 30 years
- They were built to only last 20 years, as coastal erosion encroaches the site
- But critics say visitors are making the erosion worse by not staying on paths
A report released earlier this year found the front portion of 22 Rottnest Island Authority (RIA) holiday bungalows at South Thomson Bay were at risk from erosion.
It recommended renourishing eroded dunes in the short term and then a “local retreat” for at least three cottages, and possibly up to 12.
A couple of kilometres down the road, 83 “glamping” eco-tents were opened at Pinky’s Beach on the northern side of the island in March this year, under a 20-year lease arrangement.
Coastal engineer Matt Eliot, who was commissioned to assess the site for development, said permanent infrastructure must be set back 90 metres from the coast under state planning laws.
But he said the oceanfront tents were able to be set just 8 metres back from the dune crest at Pinky’s Beach due to their temporary and moveable nature.
Mr Eliot said the site would have been completely unsuitable for a standard development.
“Instead they’ve gone down the path of something that has a limited lifetime, so it is not subject to the longer-term coastal erosion that is expected over longer periods of time,” he said.
“This is probably the first example we have where we have a site that we are choosing to operate very close to the coast and we are choosing to do so by having facilities that have a very fixed lifetime.
“That means that we are not considering permanent infrastructure and importantly we’re choosing not to defend.”
Not everyone happy with new venture
Not-for-profit organisation The Rottnest Society raised concerns when the development was first flagged that it would lead to dune degradation and increase the likelihood of erosion.
Within a few months of the resort opening, a winter storm caused erosion damage.
It washed away sand and forced the closure of new stairways which had been built by the developer to protect the dune from increased foot traffic.
The accessways have been reinforced with sand and limestone rubble and the beach has returned to its normal state.
But the Society’s Ian MacRae, who worked for 25 years with government authorities as a regional planner and policy planner, said their concerns remained.
“We predicted that there would be erosion where the accessways come through and that happened far faster than we even predicted,” he said.
“Our concern at this site over the future years is that it will need very active management, there will be a need for planting regularly and fencing in areas where they simply haven’t fenced now.”
People still tramping over dunes
When Mr Eliot prepared his report for the developer two years ago, he recommended clear accessways and fencing would need to be built to keep people off the dune, as well as ongoing management through revegetation.
The ABC took Mr Eliot to the now completed development to inspect the dune.
He found while accessways and fencing had been built, more work was needed given people were ignoring the accessways and the dune had been damaged.
“If you destabilise the dune you will end up with sand pushing landward, and that is actually a mechanism for beach erosion,” he said.
Tim Crosland from Discovery Rottnest Island said the Society’s concerns were valid and the developers were carefully managing the sand dune on the development side.
He said the foredune on the beach side was the responsibility of the RIA.
“I concur with the Society and I agree with what they are saying in terms of keeping people off the dune and just keeping it through those managed access areas,” Mr Crosland said.
A spokesman for the RIA said there was a landscape management plan for dune system at Pinky’s Beach.
“While this is the responsibility of the RIA, Discovery Rottnest Island has undertaken to complete a planting regime next year,” the spokesman said.
Development designed for erosion
Mr Crosland said while the dune had remained stable for decades, the development had been designed with the possibility of erosion in mind.
He said the tent frames had a 20-year life expectancy, while the canvas was expected to survive between 10 and 15 years.
“If there is an issue or the land moves, we can move. That is why we did this,” he said.
The RIA beachfront cottages at South Thomson Bay were under more imminent threat from erosion.
South Thomson Bay was labelled the second-worst hotspot for coastal erosion in WA, with the beach gradually creeping back at a rate of about 20 centimetres per year.
It had eroded to a point where there were now only a few metres between the dune crest and some of the cottages.
Mr Eliot, who prepared the report for the State Government, said if the Pinky’s Beach development proved successful, a similar kind of moveable, short-term asset could be developed at Thomson Bay to replace the cottages.
“This is an example of a site where we know that we have a certain amount of time with retreat, so we could be considering shorter structural life accommodation,” he said.
“Something that can be removed and retreated if we have further progressive erosion.”
But Mr Eliot said it remained to be seen whether the model would be a success.
“If the costs and management make it impossible to keep actively protecting the dunes and then you end up with blowouts driving sand into the tents, the tents would become unpopular and damaged,” he said.
“Essentially if it is a loss for the developer and it’s a loss for Rottnest, that would be a disaster.”
Mr Eliot said a decision should be made on whether to remove the South Thomson Bay cottages sooner rather than later.
He estimated they could survive another 10 years with careful and ongoing dune management.