'It's disgusting': Algae takes over Stanley Park's Lost Lagoon

CBC

2 days ago

Vancouver's Lost Lagoon serves as a northern gateway to the city's downtown, the tissue that connects the urban core with the natural beauty of Stanley Park. But the body of water is blighted by an algae bloom, covering huge sections of the lake's surface.
The algae has returned each summer in recent years, but according to nearby residents and regular visitors, this year's bloom is the worst it's ever been. When the wind blows in the right direction, you can even smell the decomposing slurry.
"It is disgusting," said Stephanie Ryan, who lives in an apartment overlooking Lost Lagoon. "Frankly, it's sort of a shame that the bloom is happening in peak tourist season. There's like a million people biking around the lagoon every day, and this is what they get to see?"
Ryan remembers previous seasonal algae blooms, including the one in 2022 that coincided with a carp die-off in the lake.
But she says none has quite compared with this year's.
"The algae seems to be really thriving, and I'm not an expert, but it feels like the lagoon shouldn't be full of algae. And yeah, I always worry about the birds and wildlife," said Ryan. "It's sort of a scourge."
According to Chad Townsend, senior planner with the Vancouver Park Board, it's difficult to assess how this year's bloom compares to previous seasons, but he said the park board has received more complaints about it this year than ever before.
"Now, in the condition that it's in and due to decisions made in the past, we have a lake that's in a very unhealthy condition," said Townsend.
He said infilling over the years has left the entire lake about a metre deep, and it's been contaminated by heavy metals and runoff from Highway 99, which now separates Lost Lagoon from Coal Harbour and the sea.
The shallow, stagnant water is vulnerable to warm spells and nutrient imbalances that lead to the algae blooms, according to Townsend.
Altered ecology
It wasn't always like this. Lost Lagoon used to be an actual lagoon, connected to Coal Harbour and tides that would flush it out daily. Townsend said local First Nations used to have settlements along its northern shore, and shellfish was harvested when the tide went down.
A little more than a hundred years ago, work began on the causeway that now connects downtown Vancouver to Stanley Park and the Lions Gate Bridge.
That work essentially created a dam, disconnecting the lagoon from the sea and daily tides.
Over the years, Lost Lagoon was used by boaters and ice skaters during cold snaps. Now it's left to waterfowl and any other creatures willing to brave the contaminated water.
What's the fix?
Townsend can imagine a future when the lake is reconnected to the sea, and the stagnant water is refreshed daily, but he said it's just one possible solution to the problem, and would require further discussions with local First Nations and other levels of government.
"The projects that we're talking about are significant infrastructure projects. They're not easy fixes of putting in a fountain or harvesting the algae. it's not going to significantly influence the conditions that we see today, so it would be a major project," he said.
Townsend said one estimate priced the reconnection to Coal Harbour at about $20 million, and it would take years to complete the project.
"It does take time to turn back the clock on some of these ecosystem changes, but I believe it's possible."