ORC’s Acting Team Leader River Management, Simon Whitton, says following the recent high winds, ORC’s Engineering staff have been actively inspecting the Lower Clutha, Toko, Shag River and the Lower Taieri Flood Protection & Drainage Schemes.
“We’ve had staff out on the ground since the high winds and this week are undertaking helicopter surveys to quickly and accurately locate all trees that might require removal from rivers in more remote locations across Otago,” Mr Whitton says.
“This survey work will help us to identify fallen trees, assess the risk, if removal is required and plan the work required in each catchment. We will act where they present a flood risk and or could be swept downstream and damage bridges or culverts, create a dam or exacerbate erosion,” Mr Whitton says.
So far, no significant damage has been identified to bridges or flood infrastructure, but numerous privately owned fences, including riparian fences, have been damaged or destroyed due to fallen trees and debris, he says.
The extent of the work programme required to clear trees and debris, and the timeframes are still being determined over the next week, but the work programme could yet expand from weeks to potentially months, he says.
While in many locations stands of willows were downed, Mr Whitton says overall there was a mix of trees damaged, including gum, poplar and macrocarpa.
Investigations so far
So far staff from ORC’s River Management Team have completed multiple walkovers, primarily around the Pomahaka, Tokomairiro, Lovells Creek and Shag rivers.
A heli flight on Monday (3 November) took place around the Milton, Lawrence, Catlins and South and West Otago areas; the waterways being the Tuapeka, Wetherston, Waitahuna, West Tokomairiro, North Tokomairiro, Pomahaka, Waipahi, Heriot Burn, Waiwera, Kuriwao, Tahakopa, Puerua, McClennan, Kaihiku and Ōwaka.
A further heli survey also took place on Tuesday (4 November) on the Taieri, Kyeburn, Swinburn and Shag Rivers.
ORC’s Manager Science, Tom Dyer says work to date is being funded out of existing budgets for river management.
“Weather events often require us to respond by reprioritising planned work programmes,” he says.
“Inspections and customer inquiries are expected to continue over the coming weeks and will help build a comprehensive understanding of the storm’s impact on local infrastructure, but if you have tree damage on your property that you think we should know about, please get in touch,” Mr Dyer says.
ORC’s Pollution Hotline: 0800 800 033
