Devils Nook landslip requires lengthy solution

Kempsey Shire Council is continuing to monitor the site of a significant landslip 6km east of Bellbrook, with the area still vulnerable to changing conditions the clearing of the whole road is likely to take months.

The landslip started approximately 85 metres above the roadway, taking out tonnes of rock and debris which eventually covered the entire roadway and forced council to close the road on Monday 4 January.

How the road was cleared

Council staff quickly swung into action, working with specialist contractors and geotechnical engineers to plan the best method for clearing and stabilising the site. A specialised team abseiled adjacent to the face of the slip to inspect the stability and depth of the issue.

After the slip was determined too dangerous to work beneath in heavy machinery, Council arranged an external contractor to use a water bombing aircraft to loosen the surface of the slip, enabling the team to commence working under the slip face throughout the weekend.

Council staff worked hard to implement several control measures to secure the slip before one lane of the road was deemed safe to reopen on Sunday 10 January.

The measures involved three lines of defence. The first being the creation of an earthen bund wall which involved crews built up a pile of the rubble from the slip into a wall that would prevent further material from falling down the slip.

The second line of defence was to install a line of large concrete barriers. The third was situating a couple of shipping containers, half-filled with rock, to act as a shield for the road and to catch any material that might potentially pass through the first two lines.

What next?

Despite these measures the site is still vulnerable and may need to be closed again if staff or specialists have concerns due to further wet weather or other factors.

Given the complexity of the slip it is hard to estimate how long it will take for Council to restore the site to full functionality as it is not just a simple matter of clearing rocks from the other lane.

Council will begin removing material in the short term once resources can be allocated however the road will remain one-lane only until a permanent solution can be designed and implemented. Staff will inspect the site daily to ensure the controls that are in place are working effectively.

Residents and visitors travelling through the site should exercise caution and never walk through on foot.

/Public Release. This material comes from the originating organization and may be of a point-in-time nature, edited for clarity, style and length. View in full here.