Foreshore Erosion Response
The dynamic coastline at Inverloch has been experiencing significant erosion in recent years, impacting on public access, amenity, and major assets.
The Department of Environment, Land, Water and Planning (DELWP), together with Council, Parks Victoria, Regional Roads Victoria and the West Gippsland Catchment Management Authority, have formed a working group to address erosion at Inverloch and developed a short-term erosion control plan for key areas along the Inverloch Surf Beach.
As part of a trial using a new erosion control method, wet-sand fencing was installed in March 2019 in two areas along the Inverloch Foreshore, which were significantly impacted by coastal erosion. The areas were renourished with sand in June, reconstructing the foredune to 1.5 metres above the beach level and five metres wide between.
Due to a number of storm events along the Inverloch foreshore over the past few months affecting the wet-sand fencing trial, the fence has been redesigned with a replacement of the front fence at each of the two sites to be completed during September 2019.
These works have been jointly funded by the Victorian Government’s Protection of Victoria’s Iconic Beaches and Coastline project, Council, Parks Victoria and Regional Roads Victoria.
The Inverloch surf beach has experienced further significant erosion in early September 2019. Due to the potential impact on built public assets including the Inverloch Surf Lifesaving Club building, Council, in collaboration with the multi-agency Inverloch erosion working group have arranged for an earthmoving contractor to relocate more sand from the beach further east to the affected areas. This work commenced on 9 September and is considered an immediate short-term, urgent response to protect the assets.
This sand placement is sacrificial and it is accepted that it may be lost in future erosion events. The sacrificial sand will provide a buffer to protect assets and prevent further erosion whilst other works are organised, including the option to construct a wall made from large sand filled geotextile containers to protect the Inverloch Surf Lifesaving Club building. The trigger points determined by the multi-agency group 12 months ago to implement harder engineering options have now been reached and planning is underway.
The worst of the storm surge season will come to an end in the next six weeks and strategic long term discussions are continuing by the multi-agency Inverloch erosion working group. Discussions are focussed on the recent rate of erosion, evidence based decision making based on studies and accessing State and Federal funding.
While the Inverloch foreshore is protected from the strong westerlies associated with the mid-latitudes, it is vulnerable to southerly winds and storm surge events. These storm surge events are particularly strong in winter, while spring and summer are times of calmer weather, allowing for more sand accretion. In recent years, the volume of sand lost to erosion during storm surge events has greatly exceeded the amount returned to the beach during calmer seasons.
Areas of Concern
The two major areas of concern are the foreshore in front of the Inverloch Surf Life Saving Club and the foreshore in front of Bunurong Road, as erosion threatens to impact built public assets.
The foreshore adjacent to the Inverloch Surf Life Saving Club has seen 33.5 metres of coastline retreat since 2012. Currently, the building is located 16 metres from the face of the dune, with this distance remaining relatively stable since the end of winter.
The foreshore adjacent to Bunurong Road, particularly near the Surf Parade intersection, has experienced 35.6 metres of coastline retreat since 2012. The road is currently within six metres of the eroding edge.
Wet-sand fencing is an erosion control structure installed from the estimated maximum erodible level of the beach. Constructed using thin slats of timber connected by wire, it helps to accumulate and maintain sand, working to rebuild a beach for improved community use.
The structure allows waves to pass through carrying sand while limiting the amount that returns offshore. This is due to its design decreasing the wave energy, allowing sand to settle more easily behind the fence.
Why Wet-sand fencing?
• Low cost and quick to install.
• Minimal impact on the environment.
• When combined with renourishment, retains considerably more sand than renourishment alone.
• Encourages vegetation to advance and help rebuild a beach.
DELWP are working with all stakeholders involved to prepare medium and long-term options for Inverloch Surf Beach. Community engagement will be central to future planning, and we will keep the community informed as the project progresses.
For further information regarding coastal protection works at Inverloch, please contact the DELWP Traralgon office on 03 5172 2111.