Neighbours kept away after clifftop landslip

Mornington Peninsula mayor Anthony Marsh said a council worker, aged in his 50s, suffered lower body injuries while doing an inspection relating to an earlier slip.

More than half a dozen properties surrounding the house will have to remain empty until at least Wednesday night.

"Those investigations are ongoing, but there's obviously unstable land, so we need to work out exactly what's going on there," Mr Marsh said.

Nearby residents can't return to their homes until safety assessments are completed. (Diego Fedele/AAP PHOTOS)

"It's devastating for the owners and it must be a huge concern for the close residents around."

The residents' access to their properties, most of which are holiday homes, will depend on results from geotechnical engineers' inspection of the site.

University of Melbourne geomorphologist David Kennedy said building heavy structures such as houses on top of sea cliffs destabilised soil and could trigger slides.

"That can happen by putting weight on top of the cliff, it can also happen by building on the cliff face itself or even at the base of it," he said.

"The debris supports it and once you remove it that starts to make things a lot more unstable."

Another minor landslip took place in the early hours of January 6 at the $2 million property, which prompted its owner to contact authorities.

An expert says building on top of cliffs can destabilise soil and trigger land slides. (Diego Fedele/AAP PHOTOS)

Other houses in the area had reportedly been deemed unsafe in the past year local resident Tanina Osborne said.

"I think that entire hill is going to have to be looked at," she told AAP.

"It would be an engineer's nightmare."

Ms Osborne said a water outlet near their daily swimming spot had been gushing into the bay three weeks earlier because of a water main issue on a road above the landside.

"That could have contributed as well, I don't know," she said.

"I'm not an expert, but you know that whole hill just has a lot going on."