Landslide Reparation – Esplanade, Mt Martha
Update Friday 18 December 2020
The owners of the property cut off by the landslip will have access again by the end of today. Today, an asphalt seal will be placed over the reinstated driveway and bollards installed to prevent vehicles driving beyond the property into the slip area.
Bore drilling for rock samples has proceeded on time and the final bore hole adjacent the Esplanade will also be completed today.
The core samples obtained from the bores will be analysed and a digital model of the slope will be developed to inform the engineered design for rehabilitation of the slip site. The results are expected in late January 2021.
There has been minor erosion of the slip site due to recent rains, however this has stabilised and there is no evidence or concern for further movement of the slope. Regular ongoing monitoring of the site continues.
Traffic on the Esplanade will be impacted between 9am and 3pm today due to the drilling, otherwise the Esplanade remains open. The service road continues to be closed to through traffic.
Update Monday 7 December 2020
- An engineered design to provide temporary vehicle access to the property that was cut off has been finalised. Works are planned to commence this week and expected to take two days to complete.
- From 14 December residents will see further activity with drilling of three bores near the service road above the Esplanade. The bores will obtain samples to determine the strength properties of the rock and soil and determine the depth of groundwater. These works are expected to take three days.
- Two further bores, lower down the hillside nearer the Esplanade are also planned before Christmas. Facilitating this will likely impact traffic over two days.
- Revegetating the area is an important element to addressing the environmental impacts of the slip and to assist in stabilising the slope. To ensure successful regrowth, this will be completed after all engineering works.
- Speed limits on the Esplanade remain at 40km/h in the vicinity of the slip. The service road remains closed to through traffic, however residents can access their properties.
Update Thursday 19 November 2020
While geotechnical investigations continue to identify an appropriate long term solution, the Shire is also working on provision of a temporary vehicle crossing to provide access to the one property that was cut off. These works are being treated as a matter of priority in the hope access can be provided for summer.
We continue to monitor the site, however there has been no movement detected across the top of the slip site. Some minor erosion has occurred as a result of the natural process of water seepage, but this raises little concern.
South East Water completed a CCTV inspection of sewer pipes in the area of the slip and found no indication of lateral shifting or displacement associated with the land slip. As a precaution, a plastic sleeve was inserted inside the full length of this sewer to minimise any movement that might result if further slippage occurs. Fire plugs in the area have also been checked for leaks.
Communication has also begun with the Bunurong Land Council to consider cultural heritage requirements arising from the slip and associated works.
The Esplanade is open to traffic, however speed limits remain reduced to 40km/h due to waterfilled barriers narrowing the roadway. The service road remains closed to through traffic.
Update Thursday 22 October 2020
The Shire has been closely monitoring the slip site and surrounding areas for evidence of further ground movement since the incident. The results of both surveying and photographic recording to date have shown insignificant movement on site. Monitoring will continue, however the results provide confidence the risk of further slips has lessened.
The geotechnical investigations commenced by the Shire and the Department of Transport continue. The Esplanade remains open, with temporary speed limits in place. The service road remains closed.
Update Monday 12 October 2020
Following successful completion of works to batter back the vertical face created by the landslip, the Esplanade was opened for traffic shortly after midday, Monday 12 October.
The works involved a long reach excavator removing material (weight) to prevent further slippage and damage to services and has significantly reduced the risk of further slippage. The additional works required further impact on the service road which remains closed to through traffic.
The Shire and Department of Transport will continue to work collaboratively on detailed geotechnical investigation. The investigation will involve a number of boreholes to obtain samples to determine the strength properties of the rock and soil and determine the depth of groundwater.
The results will then inform the design of an engineered solution to support the slope and service road.
Update Thursday 8 October 2020
Heavy rain overnight has caused further slippage, however all material was contained in a bund constructed by VicRoads and did not block the Esplanade. The slips exposed the Telstra lines running under the service road, however no other services were exposed or impacted. Telstra are on site assessing requirements.
Today’s works will necessarily focus on removing the recently slipped material and creating a platform for a long reach excavator to complete the intended works on Friday.
It is anticipated the Esplanade will need to remain closed until Monday afternoon (12 October 2020) to allow completion of works and site clean-up, however this will become clearer as works progress tomorrow.
The service road remains closed.
At approximately 2.30pm on Tuesday 29 September 2020 a landslip started at the edge of the service road above the Esplanade, Mount Martha.
Where is the landslip located?
The landslip occurred on the slope above the Esplanade, between Ellerina Road and Bradford Road.
A landslip started at the edge of the service road above the Esplanade and slid down the steep slope finishing on the far side of the Esplanade, completely blocking the road. It is estimated 30 tonnes of material and vegetation was dislodged.
Was anyone injured?
Fortunately, no pedestrians or vehicles were in the immediate vicinity when the incident occurred and no one was injured.
What has been done to clear the site and make it safe?
- The Department of Transport and the Mornington Peninsula Shire are working in collaboration to resolve this issue
- The Shire has closed the service road to all through traffic
- Contractors are working to clear the road and loose, unstable material from the slope. Pipe extensions have been fitted to broken stormwater drains and drainage has been cut/cleaned to enable water to flow to the nearest culvert
- Geotechnical investigations are underway to determine the cause of the slip and provide advice on remediation.
Are the surrounding houses at risk?
There is no concern for the structural integrity of the houses above the landslip. Access to one property has been cut, however the remaining properties remain accessible.
Is there risk of further collapse?
There is a risk of further collapse. The Shire is inspecting the site daily to check for any movement or change to the slip and the surrounding area. We are currently arranging an excavator to remove further material (weight) from the slope in an effort to prevent further collapse. This is being done in accordance with geotechnical report recommendations.
Pedestrian barriers have been erected along the service road to keep people well back from the edge of the slip.
Have utility services been affected?
The water, gas, sewer, telecommunications and power services remain intact. Utility service providers have been notified of the event.
An inspection of the gas mains has been completed and service proving/locating of the other services is occurring.
When will the Esplanade reopen?
The Esplanade reopened Monday 12 October.
Have the residents been kept informed?
The Shire is in contact with the directly affected properties.
Residents, landowners and interested parties are encouraged to monitor this webpage for updates.
Esplanade, Mt Martha, Mount Martha 3934 View Map