Jessica was building a new house in point cook.The house lot was alongside an older property, built in 1962, belonging to Anna.At the time of building Anna and her husband John (now deceased) were aware that the sandy soil on which their house stood could be unstable. With this in mind, their land was retained by a wall on all sides save for the frontage to Lallen Street. The house was situated in the middle of the block.

The eastern boundary of the Anna's land adjoined Jessica's property. On that boundary on Anna's property a concrete driveway extended south from Lallen Street to a brick carport, followed by a further section of driveway and a brick garage. The driveway, carport and garage were positioned at a slightly higher level than Jessicas property.

The plans for Anna's land included a basement carport with an access ramp adjacent to Anna's eastern boundary. The construction of the ramp required extensive excavation along the common boundary which in turn required a retaining structure to prevent movement of soil under Anna's property and to prevent possible damage to their buildings and driveway. A retaining wall was constructed.Soon after a section of the soil beneath the carport on the Anna's property subsided causing damage to the carport, driveway and house.

Could Anna potentially be held liable for private nuisance? in answering this question rely on prima facie unreasonable as there is material damage to Anna's property.