Mussels limit milfoil moves – City of Vernon says restrictions on lake weed harvesting degrading quality at Kin Beach

November 21, 2020

Castanet – November 21, 2020

Vernon city council wants more information on Rocky Mountain ridged mussels and how their protection is limiting Eurasian milfoil management in the east arm of Okanagan Lake.

Council will discuss the matter Monday, following provincial restrictions this past year on Okanagan Basin Water Board rototilling at Kin Beach and nearby areas to protect the endangered species.

A report to council states rototilling has proven to be the most effective management tool to deal with the lake weeds and to maintain the quality of swimming areas.

With the discovery of the mussels in multiple beach areas previously not inventoried, council is expected to direct administration to identify and investigate the underlying science related to the mussels and their related endangered listing.

The mussels – unrelated to invasive zebra and quagga mussels – were listed as endangered in 2010.

Since then, they have been found in large numbers at multiple sites in the Okanagan basin, including recently in the water off a proposed new dog park, and water intake site at the north end of Kin Beach.

The restrictions stopped rototilling as a management method for controlling milfoil, and restricted management to in-season harvesting of their tops only. 

The net impact has been a consistent lowering of the quality of the Kin Beach swimming area.

The water board questions the impact of rototilling, as the mussels have been found in significant numbers in areas where rototilling has been taking place for decades.

The restrictions had a big financial impact on the new water intake off Tronson Road, with the cost to move the mussels estimated at $25,000 per mussel.

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