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Report suggests fixes for Quamichan’s toxic algae problem

Numerous strategies recommended
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North Cowichan is taking steps to address toxic algae in Quamichan Lake. (Citizen file)

There’s no silver bullet that will reverse decades of neglect in Quamicham Lake, according to Jim Cosh.

This neglect has led to blooms of killer toxic algae in the lake at certain times of year.

But Cosh, a spokesman for the Quamichan Lake Water Quality Task Force, said concentrated and persistent actions can start a “trajectory of improvement” to the lake’s water quality over time.

Based on the report of the task force, which was presented to North Cowichan’s council on July 19, council voted unanimously to implement a number of recommended strategies to deal with high nutrient levels in Quamichan Lake.

They include a program to manage and reduce nutrient loading in the lake, extensive monitoring to determine the effectiveness of the strategies to reduce the nutrients and the introduction of a public education program on the issue, including the posting of signs around the lake.

Those strategies to lower the amount of nutrients entering the lake could include mandating construction companies working on sites in the area to better control and monitor their run off, weaning more people off septic fields and onto sewer systems and even encouraging residents to use less fertilizer on their lawns.

As for strategies to lower and/or eliminate the blue-green algae that is currently in the lake, North Cowichan will consider the construction of a prototype to skim the algae from the lake, aeration to help treat water before it makes its way into the lake, and adding species like crayfish and more trout that would help reduce its nutrient levels.

“It’s estimated that about 2,000 kilograms of nutrients a year are entering the lake, and more is coming in than going out,” Cosh said.

“If we can just swing the balance and allow less than that amount of nutrients entering the lake than going out, it would go a long way to address the lake’s problems.”

There have been at least four reported dog deaths around Quamichan Lake last year, and all are suspected to be caused by ingesting toxic blue-green algae from the lake.

North Cowichan decided to set up the task force, consisting of staff and Mayor Jon Lefebure as chairman, along with water specialists, to study and seek solutions to the ongoing health issues related to the algae soon after.

As expected, the task force concluded the nutrients that are causing the algae outbreak in the lake are coming from a number of sources, including urban runoff, and runoff from nearby agricultural lands, construction areas and logging sites.

Lefebure said that while the municipality is moving forward with its strategies, he expects a “long a difficult road ahead” to deal with nutrients in the lake.

“It will require efforts to try and change people’s behaviour and the way they do things, and I don’t think that will be easy or accomplished quickly,” he said.

“At first, our goal is to try and reduce the severity of the nutrient loading into the lake, and our long-term goal is to create a more natural balance there.”

Lefebure said that while the total costs of the strategies to deal with the lake’s issues have yet to be determined, the first task is to establish monitoring of the nutrient levels in the lake and their sources, which is expected to cost “in the tens of thousands of dollars”.

“Staff have been asked to write a report on the issue, with a suggested budget,” he said.