Clyde Mountain Slope Stabilisation
Roads and Maritime Services has completed the $3,100,000 Clyde Mountain slope stabilisation project. Work has involved slope stabilisation and rock removal from above the highway followed by the installation of permanent structures and treatments to better stabilise the slope above and below the Kings Highway just west of Pooh Corner.
Stage one of the slope stabilisation project, involving the clearing of vegetation and removal of hazardous rocks and debris from above the highway, was completed in July 2013.
For the safety of workers and motorists, a five week program of 57 hour closures on the highway was required. Roads and Maritime consulted with the community on the timing for the closures. Over the five weeks of planned closures over 800 cubic metres of unstable rocks, boulders and debris and over 400 cubic metres of trees and vegetation was removed from above the highway.
Clearing the slope of vegetation allowed the project team to get a better look at the slope itself so that the unstable areas of rock and debris could be identified and removed. The team removed hazardous materials with the use of long reach excavators and by hand scaling where workers suspended from harnesses used crow bars to loosen hazardous sections onto the road below.
Temporary measures such as rock bolts, wire rope and netting were installed to reduce short term risks until the more permanent structures were provided as part of stage two.
An additional 600 cubic metres of debris was dislodged in week five of the program by a landslip in the worksite. Work planned for week five of the stabilisation project was carried out at the same time as the landslip clean up so that no further full closures were required. See the recent landslips on Clyde mountain page for more information on the landslip and clean up.
Roads and Maritime completed Stage 2 in August 2014. Work involved the installation of permanent structures and treatments to better stabilise the slope above and below the Kings Highway just west of Pooh Corner.
Robust fencing, rock fall mesh, rock bolts, concrete buttresses and netting have been installed to reduce the risk of future landslides onto the road.
Further measures of stabilisation included concreting over large sections of the slope to prevent any rock fall. Improved drainage both above and below the road will help to divert water away from problem areas and large rocks were anchored to the mountain with bolts and screws.
Work to stabilise drainage pipes on other areas on Clyde Mountain has taken place throughout the stabilisation process.