Investigation And Monitoring Of A Slow Moving Landslide

Allan Garrard, Tony Miner and Colin Macdiarmid

An area in the township of Clifton Springs called The Dell is a prominent coastal amphitheatre feature of the Bellarine Peninsula in southern Victoria. The local community and visitors to the area have used the Dell as a safe access point to Corio Bay and for its recreational facilities.

The Dell is located within the area previously utilised as a Hotel Resort in the late 1890’s until the 1920’s. The groundwater springs, after which the township of Clifton Springs is named, emerge at the foreshore. The mineral springs have been known and utilised dating back to the early 1800’s. Development of the springs and a hotel resort was constructed in the 1870’s.

A long and continuous tension crack near the crest of the amphitheatre developed during the latter months of 2001 and has since increased in length and width. Visually observed acceleration of slope movements prompted the authorities to close and seal off the area.

The slow moving landslide has since been subject to geotechnical and hydrogeological investigation and monitoring of ground movements, surface movements and pore water pressures.