Terms of Reference

Q: What was the cause of the McCrae Landslide?

A: Water from a burst water main owned by SEW and located near the corner of Bayview Road and Outlook Road.

Q: Were actions or decisions taken before the McCrae Landslide to prevent or mitigate landslides? If so, were they adequate?

A: Yes, limited actions were taken.

In particular, at some point between 2012 and 2019, the Shire adopted an informal practice of imposing additional planning requirements on properties that were mapped by geotechnical experts as falling within high landslide susceptibility areas. The practice was intended to protect areas prone to landslide, by minimising land disturbance and inappropriate development. This measure, however, was not an adequate substitute for imposing an EMO over those areas.

Q: Were actions, decisions or omissions made that may have contributed to causing the McCrae Landslide?

A: Yes.

Two omissions stand out.

SEW’s delay in locating the burst water main may have contributed to the McCrae Landslide.

The burst water main was located nearly five months after it first started leaking, two months after residents first noticed water rushing along and surfacing on streets uphill of Penny Lane, and six days before the 5 January 2025 landslide.

The Board of Inquiry is, however, unable to determine whether delay contributed to the McCrae Landslide given that this was not the subject of expert evidence. Of course, had the leak been identified and repaired very shortly after it began, the McCrae Landslide would not have occurred. However, the evidence does not establish the critical threshold or timing at which intervention would have averted the event.

Further, that the Shire and SEW did not take steps after the 5 January 2025 landslide to try to intercept the subsurface water flow upslope of the landslide site, and direct it away from the site, may have contributed to the McCrae Landslide.

The Board of Inquiry is, however, unable to make a positive finding on this matter as the experts were unable to opine whether taking such steps would have sufficiently lessened the likelihood of the McCrae Landslide occurring.

Q: Were risk assessments undertaken to determine the likelihood and severity of landslides in McCrae before the McCrae Landslide? If so, were they adequate?

A: Yes.

Significantly, in 2012, the Shire received a geotechnical report which classified the McCrae escarpment in the vicinity of 10–12 View Point Road, as well as other areas in the Mornington Peninsula, as exhibiting high landslide susceptibility.

The assessment in and of itself was adequate as a guide to expected landslide susceptibility. What was inadequate was the Shire’s use of the assessment. The Shire did not commence updating its EMO schedules to incorporate areas identified in the report as having high landslide susceptibility.

Q: Were there any barriers to the implementation of measures to prevent or mitigate landslides in McCrae that existed before the McCrae Landslide occurred?

A: Yes.

There are regulatory barriers. Notably, there are limitations on the ability of current statewide planning policy and tools to manage landslide risk. Further, the regulatory framework relevant to how local councils and landowners manage landslide risk on private land is limited.

Q: What is the regulatory framework in relation to the prevention and management of landslides in Victoria?

A: The regulatory framework is fragmented. Various statutes directly or indirectly support the prevention and management of landslides, including the Planning and Environment Act 1987 (Vic), Building Act 1993 (Vic), Building Regulations 2018 (Vic), and the Emergency Management Act 2013 (Vic).

Q: What measures could be taken for the prevention or mitigation of the risk of a similar landslide event to the McCrae Landslide occurring in the future in McCrae?

A: A range of measures are available, and they need to be implemented by multiple organisations and agencies. The measures include imposing an EMO on parts of McCrae that are known to be at high risk of a landslide; managing water infrastructure; improving processes and procedures; developing comprehensive plans for responding to landslide events; and educating the community.