Climate change threatens survival of Cowichan River

David Anderson, Vancouver Sun, September 23, 2106

During my time as federal Environment and Fisheries Minister I experienced firsthand how climate change was affecting Canada’s environment.  It is by far the most critical challenge that governments of the world are facing. It is not a problem for those living far away or a problem for far in the future. Climate change impacts are showing up right here and they are showing up now.

The Cowichan River Basin is in its third consecutive year of drought and in its eighth drought year since 1998.  The Cowichan River is the lifeblood of the Cowichan Valley. Its salmon runs have sustained the Cowichan First Nations since time immemorial. It supports both commercial and sport fisheries, and replenishes the aquifer that provides water for local agriculture and the City of Duncan’s thousands of residents.  The river also provides water for Catalyst Paper’s Crofton mill, supporting 600 jobs that are vital to the region’s economy.

When the mill was built in 1957, a weir was erected at Lake Cowichan at the head of the river, to provide higher water flows to the river during the summer. By storing water on the lake in the spring, the weir enabled moderate but continuous flows in the river over the summer until the autumn rains arrived in mid-October.

For 60 years the weir worked well, releasing enough water for salmon and trout through the summer months, while enabling agricultural, municipal, recreational and industrial uses. The builders of the weir, however, did not foresee our changing climate and the impact this is having on Cowichan Valley rainfall patterns.

According to Kerr Wood Leidal, an independent engineering firm, climate change has caused a reduction in the basin’s precipitation by approximately 30 per cent over the past decade compared to the previous 50 years.

This year, Cowichan Lake experienced the lowest late-May water level since the weir was built. According to the Cowichan Watershed Board, unless there is substantial rainfall the lake is expected to hit its zero-storage level by the end of September.  That means the river will run dry.

Catalyst Paper is spending $500,000 to rent and install 20 pumps in Lake Cowichan in the event it’s necessary to pump water from the lake into the river to protect its water source.  While the pumping operation is workable, it is also short-term. The best long-term solution is to raise the height of the weir to enable it to hold more water in the lake during the spring and early summer months. Studies have found that to adequately rebuild the weir will cost $10 to $15 million.

The Cowichan Watershed Board, comprised of representatives from the Cowichan Valley Regional District, the Cowichan Tribes, community members and representatives appointed by the federal and provincial governments, has been considering this for some time. The Board agrees that a long-term solution is required. Clearly, this is a case where governments and stakeholders need to come together to help mitigate the effects of climate change on a precious and important natural resource.

Unfortunately, while our federal and provincial governments talk the talk on climate change, they have yet to show real leadership to climate change problems such as those of the Cowichan. Financial help from senior governments is needed in the near future to fund two studies: one to determine the optimal summer flow needed to protect the river as climate changes continue; and, based on that, the engineering and construction study as to what must be built to provide that water storage given those climate change pressures.  When those studies are completed, we then will need a manageable joint funding formula to fund re-building of the weir.

Let’s hope the current government interest and messaging translates in real action before it’s too late for the Cowichan River.

David Anderson served for 13 years as MP for Victoria.  He served in the Chretien Liberal cabinet as Minister of Fisheries and as Minister of the Environment, and for eight years was the senior minister for British Columbia.  For the past six years he has been a member of the Cowichan Watershed Board.

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