There’s some major works in progress on the Heathcote River, with dredging taking place to remove sediment, with the end goal of reducing the flood risk. You can read more at this Press article https://i.stuff.co.nz/the-press/news/101874580/heathcote-river-dredging-to-be-fasttracked-to-reduce-flooding
Christchurch Daily Photo 
One response to “Sediment removal, at the Woolston Cut, Heathcote River”
A lot of the same type of equipment would get used here.
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