Lake Dunstan turns back into a river
Lake Dunstan was formed from the Clutha River after the completion of the Clyde Dam in 1992 - but it's slowly turning back into a river, leaving the community of Cromwell with a sludgy mess.
Silt that would have washed through from the Kawarau River has nowhere to do, and is mounting up on the town's lake banks.
The lake is helping to fuel the growth of invasive weed lagarosiphon, and the built-up sludge and weed is impacting on boaties and swimmers.
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