A ghillie working on the River Dee just to the west of Banchory last week recorded this footage of a cloudy substance flowing rapidly into the river after a period of heavy rainfall.
And yesterday, a similar incident was filmed in the same area, also following very rainy weather.
Debbie Cooper, development officer with the Dee District Salmon Fishery Board and the River Dee Trust, said she believes the incidents are connected to a nearby Kirkwood Homes construction site at Inchmarlo.
She worries about the potential impact of pollution on the important ecosystems of the waterway.
The Scottish Environment Protection Agency (Sepa) said it is aware of problems at the construction site, and its officers have attended on a “number of occasions”.
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