Upper Clutha bicycle riders and walkers will need to take extra caution when accessing parts of Newcastle Track near Luggate as last week’s storm water has resulted in further erosion of an already major slip on the track. A local man, Terence (Terry) Hetherington, observed the recent washout and alerted others by posting photos of the area onto Facebook.
A geotechnical report last August for Otago Regional Council (ORC) includes a July 2018 commissioned study by ORC and describes large scale gully erosion on a terrace face on the north bank of the Clutha/Mata-Au River, which is called Reko’s Bluff. This area has been gradually changing since 2015, but the issue has worsened after recent major rainfall, including the steep gravel cliffs eroding and two alluvial fans forming in the river, which have damaged parts of the Newcastle Track.
The riverbank area is controlled by the Department of Conservation (DOC) and remains open.
ORC’s natural hazards acting manager, Ben Mackey, said “ORC has not inspected the site following last week’s rain, and management of the track itself sits with DOC. It is our understanding that the land owners are currently looking at options to minimise any further erosion.”
DOC senior ranger Annette Grieve could not be reached for comment by the time this week’s paper went to print.
The former tussock grassland, which once acted as a sponge to retain rainfall, was converted to pasture grasses in 2014. The current landowners installed irrigators in 2018, which reportedly have the potential to exacerbate erosion. The long-term impacts of the Reko’s Bluff washouts on the Clutha River ecosystem are said to be unknown.