Howe Sound's health improving but climate change poses threat to inlet: report

A new report by Ocean Wise highlights decreased industrial pollution in Howe Sound, but warns of the threat climate change poses to the marine environment.

The 388-page report, released on Thursday, is an update to a similar 2017 report on the health of the marine environment in the sound, and written to appeal to the general public and decision makers, according to Aroha Miller, manager of the Ocean Watch program at Ocean Wise.

"I'd say it's a really positive, happy story," Miller said of the findings in the report. "It's definitely improving."

Miller said the report draws on the work of multiple research groups, organizations, scientists and local knowledge holders.

She said two of the major sources of industrial pollution in Howe Sound — the shuttered Britannia Mine and pulp and paper mills — have shown dramatically reduced pollution in recent years.

The provincial government stepped in to install water treatment at the mine in the early 2000s, reducing acid rock drainage and heavy metals entering Howe Sound by 90 per cent, according to Miller.

She said regulations imposed on a pulp mill have been effective, while a second mill ceased operations.

Sea life returning

According to Miller, people have been observing more frequent visits to the sound from large cetaceans, like orcas, in the last 10 or 20 years, signalling a rebounding ecosystem.

"These large and much more obvious indicators of the health of the environment are starting to return, and that means all the levels in the food chain below them are starting to return," she said.

But the report warns of challenges ahead for Howe Sound, with increased development along the shore and things like logging continuing to have an impact. Miller said large log booms block the sunlight, preventing underwater plant growth, and the logs shed bark in the water.

The single most pressing threat to the environment in Howe Sound, according to Miller, is climate change.

"What we're likely going to be seeing is warmer temperatures, which will lead to warmer water temperatures, heavier and more intense rainfall events and less snow fall," she said, adding that more frequent and extreme storms also take their toll, causing damage, and tearing boats from their moorings, which can lead to more pollution in the water.

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