Work is progressing well at the Diana Falls slip in Haast Pass installing the most complex rockfall protection system to ever be installed in Australasia.
The posts for the second of three rockfall barrier fences, being built about 150 metres up the slip face, are in and work is underway hanging the mesh. The fence has five posts, each standing six metres tall and weighing up to 720kgs. Five tonnes of high-tensile steel mesh will be strung between the posts, across the slip face.
Work is also underway on drilling the post anchors for the last of the three fences, located at the top of the 30-metre vertical face.
When the three rockfall barrier fences are completed at the end of this month, there will be more than 30 tonnes of mesh on the hillside, in what will be the most complex rockfall protection system to ever be installed in Australasia.
Each fence will have the capacity to stop a boulder weighing up to 16-tonnes (the size of a small car) travelling down the hillside at a speed of 90km/h.
The team have completed the fine tuning of the tensioning of the mesh and cables on the first rockfall barrier fence which has been installed about 250m up the mountainside at the top of the slip.
Weather permitting, it is expected the work on the slip face will be completed at the end of the month. This will enable work to begin widening the highway at the bottom of the slip, to get State Highway 6, from Makarora to Haast township, re-opened to two-way 24/7 traffic in time for the start of the busy summer tourist season.
One of the rock catch fences being built to improve safety at Diana Falls
