Infrastructure

Accounting for geotechnical risks has been a large part of resettlement planning in Wye River and Separation Creek. During the clean-up, Grocon undertook measures to help reduce the risk of landslip, from clearing stormwater drainage lines to conducting geotechnical assessments and putting in place temporary measures. Now that clean-up is complete, pending some arbory works, Colac Otway Shire and Emergency Management Victoria have engaged geotechnical experts to guide immediate action and longer term planning to reduce the risk of landslides. Property owners also have requirements to manage risks on their property, as outlined in the Coffey Geotechnical Report. Geotechnical services are also being used to inform other aspects of the resettlement project, including waste water management options.

The local terrain already posed some challenges, however we now have the impact of the fire and the resulting change in the landscape further contributing to the risk of erosion and landslip. After a fire we see a loss of structures, vegetation and infrastructure, which means the townships have greater exposure to adverse weather such as wind and rain.

Through the guidance of geotechnical experts, temporary measures are being installed, such as barriers, fencing and mesh (where needed). Colac Otway Shire, supported by the Victorian Government, is also undertaking immediate works to improve stormwater drainage and progressively remake the drainage system and repair roads. There is close monitoring on the ground by Victoria Police, Colac Otway Shire and Grocon, who has been engaged to install retaining walls in Very High to High risk locations identified by the geotechnical experts.

An Emergency Management Team (EMT) is being coordinated by Victoria Police, who take responsibility in the event of a landslide. The EMT is monitoring the situation and working closely with Colac Otway Shire, Emergency Management Victoria, the Victorian Government, Grocon and geotechnical expert Tony Miner to ensure work is being undertaken to reduce immediate risk and plan for long term action. Victoria Police is conducting daily ground patrols for general public safety and to also observe the local environment and conditions.  EMV has also established a plan to guide an Incident Control Team (ICT), which is being overseen by the State Response Controller. At this point the Incident Control Team has not been activated.

Victoria Police is conducting daily ground patrols and geotechnical expert Tony Miner is undertaking a formal monitoring program on behalf of Emergency Management Victoria, as well as advising Victoria Police and other agencies of hazards and risks. A portable weather station has also been installed to help monitor local weather and conditions. EMV is also working with a local geotechnical expert to have electronic slope monitors installed in the High Risk areas. The monitors will provide data on any movement of the slopes for the geotechnical consultant to analyse and provide advice back to EMV and the Incident Controller on any immediate action that may be required.

As part of the work to reduce the risk of landslips, the Victorian has commissioned Grocon to undertake the replacement, repair or establishment of retaining walls in high risk locations to ensure public safety. This work is being fully funded by the Victorian Government.

Emergency Management Victoria has established a plan to guide an Incident Control Team (ICT), which is being overseen by the State Response Controller. The establishment of an ICT is undertaken when potential risks to public safety are identified and there is a requirement for ongoing monitoring and mitigation strategies.

This scope of work is currently being finalised. Grocon are following a robust process of engineering and design, and given the complexities of the site they anticipate commencing in July. In some cases there may be the need to erect a temporary solution to mitigate the risk in the short term.