Parts of the Newcastle bike track located at Hawea Flat have been gradually changing over the last few years but over the past few weeks, the problem has worsened with the steep gravel cliffs eroding and a large debris fan forming in the Clutha River.
A frequent user of the track, Eddie Spearing, came across the washout, whilst cycling along the track when the first major event happened in August 2015.
Since then, he has watched it grow bit by bit.
“The rain event on May 22  has doubled the size of the washout,” he said.
“I was really shocked. It is a wonder to me how nothing has or is being done about it. From doing a little research on Google Earth and the time lapse satellite imagery it’s easy to see when the changes occurred and it’s also obvious the land use above the washout has changed. The two things correspond.”
The cycle track weaves its way around the true left of the Clutha River; the terrain was designed by the Upper Clutha Tracks Trust and formed by the Department of Conservation. It is described on the DOC website as a track which enhances “public access to the Clutha River where walkers, cyclists and runners are able to enjoy views of the river and panoramic shots of the surrounding peaks”.
Otago Regional Council’s acting manager for natural hazards, Ben Mackey, said that ORC had been notified about the site, and staff visited the area on July 5.
“A gully has eroded into the steep gravel cliffs, and a debris fan has been formed which is extending out into the Clutha River,” Ben said.
“Geotechnical engineers have been engaged to assess the site, and its potential effect on the Clutha River.”
The Department Of Conservation is also aware of the situation on the Newcastle track as staff inspected the site on Monday, July 9, following the recent heavy rain.
An alert concerning “track damage” has been on the DOC website since May 25.
DOC is currently considering their options, with DOC representative, Annette Grieve saying, “Track damage after extreme weather events are a constant challenge for the department. The public need to be cautious on all tracks in the region and we currently have an alert on our website.”
She had no further information to provide at this stage.
Eddie believed the track would need to be re-routed soon as more track degradation occurs.
“On the other side of the river further downstream at the next river bend, the up-stream track (true right) at a particular point where the track goes very close to a cliff edge, has also been collapsing.
“It won’t be long before that section of the track will have to be rerouted. This new washout will probably speed that collapsing process up.”
He said this washout, particularly with the size it is, has further encroached into the Clutha River and is changing the whole flow of the river downstream.
Eddie also cycled the track on Tuesday July 10 and noted that the rain from the last few days further degraded the track, taking the washouts “to another level”.
Pictured: A large debris fan extending out in the Clutha River, and the washout from above. Photos: Eddie Spearing
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