In 2015, Stuart Ayres, the MP for Penrith in Sydney’s west, stood at the site of an old quarry in his electorate and told a journalist to imagine homes “as far as your eye can see”.
“There are so many opportunities we can explore,” he told Channel Nine.
“Different types of housing, larger homes, smaller homes, and all types of recreational activities will happen there.”
Ayres was talking about Penrith Lakes, a 2,000-hectare site owned by a consortium of businesses, including the Kerry Stokes-owned Seven Group through its majority stake in the building materials supplier Boral.
Eight years later, just how many – if any – homes will be built is subject to some uncertainty. Penrith Lakes is located around the Hawkesbury-Nepean floodplain, and has been among the areas inundated in the numerous floods to hit that part of western Sydney in recent months and years.
While a 2019 investor presentation from Boral raised hopes for “5000+” homes at the site, the government has cooled on its enthusiasm because of the flood risk.
After expanding the area approved for business development by 40 hectares in 2020, it has since ruled out residential zoning on the site.
Ayres, now the deputy leader of the New South Wales Liberal party, says he is opposed too. In budget estimates earlier this year Ayres said he was “categorically opposed” to large-scale residential development at Penrith Lakes.
Last year he said the suggestion he supported large-scale residential development on the site was “a politically motivated lie”. The footage, he says, was taken before flood mapping showed Penrith Lakes shouldn’t be developed on.
“Residential housing is not appropriate on the Penrith Lakes. Full stop,” Ayres said.
But as flood waters from the Hawkesbury-Nepean inundate homes for the fourth time since March 2021, the NSW government’s development plans in the city’s fastest-growing region are again under the spotlight.
While 425 square kilometres of land lie within the probable maximum flood in the Hawkesbury-Nepean valley, it has also long been identified as fertile for property development amid rising house prices and supply shortages.
Documents released through the NSW parliament reveal the Department of Planning projects that, by 2041, 12,000 new homes are expected to be built on flood-prone land in the quickly expanding north-west growth area around the valley. Local councils surrounding the valley currently have plans for several thousand more homes.
Many experts fear that is a conservative estimate, particularly if the government goes ahead with its controversial proposal to raise the Warragamba Dam wall.
This week the premier, Dominic Perrottet, again reiterated his support for raising the dam wall, indicating that his government is seeking a 50-50 funding arrangement with the commonwealth.
“I don’t want to be in a position in ten years saying we should’ve done this back in 2022,” he says.
The plan to raise the wall, which is contentious, even within the government, is often touted as a solution to flooding in the valley. While it may mitigate some floods, many experts believe it would be of limited value with potentially disastrous environmental effects.
There is also a perverse notion of the “levee paradox”, which means raising the wall could make future floods more dangerous.
“The idea is you build flood control infrastructure like levee banks or you raise a dam and it means politicians say great we can relax and develop more on the flood plain,” Jamie Pittock, a professor in environment and society at the Australian National University, says.
“But none of that infrastructure ever controls extreme flood events, and when you do increase the development it means the results are absolutely catastrophic. In Lismore they thought they were safe behind a 10m levee bank. They weren’t.”
Ayres, the biggest supporter of raising the wall inside the NSW government, has repeatedly said raising the dam wall would not be a boon for property developers.
But Pittock says it would “absolutely” lead to further homes being built on the flood plain.
There is some reason for his scepticism. In 2017 Infrastructure NSW stated in a report that the population within the floodplain was expected to increase by about 134,000 over the next 30 years, about double the current number of residents.
And some ministers have said raising the dam wall would help facilitate that growth.
“[Raising the dam wall] means that we can probably release more land in the north-west for construction and development,” the transport minister, David Elliott, said in an interview last year.
In the wake of February’s flooding, the government announced a pause on rezoning in the area until it received a report into the disaster by professor Mary O’Kane and former NSW police commissioner, Mick Fuller, which will also examine whether planning standards are fit for purpose.
The government had also paused some re-zonings at West Schofields and Marsden Park North within the valley, and at Windsor, Richmond and Emu Plains.
But many experts believe planning standards are out of date. Typically, residential rezonings are based on the level of a “one-in-100-year flood”. But many say such events are happening more frequently. Even Perrottet agreed this week that “perhaps” it is no longer an adequate descriptor of recent floods.
“Since 1967 we’ve had something like $22bn paid out in insurance claims for flood events and nearly 20% of that was incurred in the last four-and-a half months,” the chief executive of the Insurance Council of Australia, Andrew Hall, says.
Hall said the one-in-100 measure was no longer adequate in a situation where “the sorts of worst-case outcomes once predicted on paper are actually playing out”.
“We wouldn’t accept this level of risk in any other situation and yet on floods we seem to,” he says.
“Put aside the challenge of providing insurance and just ask the question: why would it make sense to put people in harm’s way, to put them at risk of, at some point in the average lifetime, of losing their homes, of displacement, trauma, intergenerational-poverty?”
While almost 12,000 new homes planned in the north-west growth area are above the one-in-100 level, they are below the probable maximum flood [PMF] level – the worst-case scenario.
Pittock is stark in his assessment of the risk of allowing thousands more people to live there.
“It is stark raving, barking mad to build below the PMF in the Hawkesbury-Nepean Valley,” he says.
“The Hawkesbury-Nepean valley in the flood of 1867 was 20m deep. Nothing is going to save a house in a 20m flood and it’s the height of stupidity to allow development in that sort of place.”
The government also faces criticism over two recent decisions that wound back planning controls aimed at curbing developments on flood-affected areas .
In March the planning minister, Anthony Roberts, scrapped a set of flood-risk design principles introduced by his predecessor Rob Stokes only two weeks after it came into force, . He also dropped a set of draft planning rules promoting more sustainable development that some, including the ICA, wanted to include flood risk.
The NSW president of the Australian Institute of Architects, Laura Cockburn, says it is “hard to comprehend why now, of all times, these principles have been cancelled”.
“We have seen the devastating results of building on flood-prone land,” she says.
“We must ensure that the much-needed housing supply doesn’t come at the cost of risk mitigation with heartbreaking consequences for the families that live there.”
