Why do they dredge the Don Valley River?

Angus Armstrong, Harbour Master at Ports of Toronto, takes us on board the Iron Guppy as it takes a containment cell on the spit at Tommy Thomson Park, towing a drop bottom scow filled with material dredged from the bottom of the Don Valley River.
Follow the Toronto Star on social media:
Facebook: / torontostar
Twitter: / torontostar
Instagram: / thetorontostar

[@miltyway]

Thank you for sharing. I will swim the Don River in 2020.