Questions raised about viability of hilltop homes after repeat Mornington Peninsula landslides

A real estate advertisement once described the house as a "sublime hillside family home" with a huge balcony that opened to panoramic views of Port Phillip Bay.

But by the time swimmers were drying off from their morning laps on Tuesday, the $2 million property lay in a splintered heap near the foot of the hill once used as its selling point.

The four-bedroom house had come crashing down in a dramatic landslide that hospitalised a council worker and saw about eleven nearby homes evacuated.

The landslide destroyed a home and injured a council worker. (ABC News: Danielle Bonica)

There are concerns about the long-term viability of the hilltop neighbourhood. (ABC News: Danielle Bonica)

A $2 million property with panoramic views of Port Phillip Bay slid down a hillside once used as its selling point. (ABC News: Danielle Bonica)

Geotechnical engineers were called in following the landslide. (ABC News: Danielle Bonica)

There have been at least two other recent landslides in the same area. (ABC News: Danielle Bonica)

One street over, real estate agents had been hoping to land a record price for a home about to be listed for sale.

Instead of real estate photographers, that home and others were filled with geotechnical engineers pondering whether the structures were safe to return to.

As the week drew to a close, residents were still unsure as to when they would be able to return home.

After details emerged of at least two other recent landslides in the same area, questions have also been raised about the long-term viability of home lending and insurance for hilltop neighbourhoods.

Karl Mallon from Climate Valuation, a firm that specialises in the risk of weather and climate change-related disasters to home ownership, said some financial institutions had begun asking his firm for detailed data on landslip risks in particularly prone areas.

He said mortgage lenders could become reluctant to lend for high-risk properties, and insurance for such properties could become similarly difficult to obtain.

"What this also raises is whether councils and building codes are keeping up with increased risk," he said.

History of landslides raises questions over risk

When the now-destroyed home last sold in May 2023, its former owner Ben Wells said it was no secret that a separate landslide about six months earlier had prompted rolling evacuation orders for some neighbouring homes.

This week, he told ABC Radio Melbourne he believed then that work to stabilise the area would start within weeks.

Instead, he and another resident said the work was stalled.

A third resident, who lived uphill of the destroyed home, suggested responsibility was being handballed between the Mornington Peninsula Shire Council and the local water authority, South East Water.

But Mr Wells said it remained the case that "people who own houses haven't been able to live in them for two years" by the time the more destructive landslide hit.

The owners of the destroyed home, Nick and Kellie Moran, said in a statement that a smaller landslip had impacted their property — almost injuring family members — in the first week of January.

Scott Chen, a civil engineer who recently visited the area, said factors including weathered soil exposed to strong sea winds, inadequate drainage systems and a penchant for hillside developments could have weakened the land's stability.

"Mornington Peninsula has a well-documented history of landslides," he wrote over email.

"However, neither the state government nor local councils have integrated landslide risk into urban planning restrictions.

"This oversight leaves many properties vulnerable to recurring incidents."

He recommended measures to improve drainage, stabilise high-risk areas and monitor slope movement and groundwater pressure — but warned large-scale implementation could easily cost hundreds of millions.

In a statement released on Friday, South East Water said preliminary data from tests taken in McCrae indicated the water was not from South East Water’s network.

The local council declined to comment on the cause of Tuesday's landslide while investigations continue.

A council spokesperson also declined to comment on the November 2022 incident, citing legal action, but said it was unclear if the incidents were connected.

A Department of Transport and Planning spokesperson said the Morning Peninsula Shire council had not requested funding for landslip rectification works.

Risk reduction program

Some locals have questioned whether water drainage was properly considered during recent developments in the neighbourhood.

A planning application search revealed approvals for several dwellings and alterations, vegetation removals and earthworks in the streets surrounding the destroyed home over the past five years.

Jay Earles, an architect who works on coastal homes along the peninsula, said on Wednesday his team often had to balance demand for height and views with important structural and engineering requirements.

"We'd be looking at consulting with geotechnical engineers, with structural engineers, prior to even putting pen to paper," he said.

Dr Mallon called for a retrofitting program to increase the resilience of any at-risk homes — particularly older ones that may have been built before more contemporary standards were in place.

"We've got properties just not ready for worsening events," he said.

"What we need is an adaptation program and grants and funding to cover the upgrade of these buildings, otherwise home owners will often not have the resources or prioritisation to get it done."