How an N.L. community is using seaweed to filter its lakes

Facing a massive bill and a looming federal deadline, town officials in Conception Bay South, N.L. are turning to algae for water filtration help.

The town council, in partnership with a local company will plant seaweed at the end of their effluent pipe in November. It’s part of a trial to determine how much cleaning the algae can do, and how much help it can be towards the town’s water filtration requirements.

“I think we would be ignorant to assume this will solve all of the issues that we have, but certainly if we’re considering a price tag of over $100 million, we want to do whatever we can,” said Joshua Barrett, a councillor in the community.

“The models show it can be a viable option… but there hasn’t been a whole lot of actual studies done in the water,” said Michael Teasdale, a seaweed farmer who runs HoldFast NL.

“Hopefully with this work, we can show whether or not it’s an option.”

Conception Bay South is one of many communities across the country that has not yet reached compliance with new federal government rules on water treatment.

Passed in 2012, new wastewater guidelines will give communities until 2030 or 2040 to get in line. They require secondary processing of wastewater, and further removal of solids and chlorine before effluent can be sent into the ocean.

According to Environment and Climate Change Canada, 77 per cent of wastewater plants met the guidelines in 2022.

But in Newfoundland and Labrador, that number is significantly smaller. According to the Canadian Council of Ministers of the Environment, only 6.8 per cent of systems in Newfoundland and Labrador met requirements.

Barrett said his town — and many others — agree that water treatment and ocean protection are important, but the price tag attached to upgrading projects has put easy solutions out of reach.

“We have a population of 27,000 people, our annual budget is $40 million,” he said.

“We consider this a priority, but we also have to plow our roads. We have to ensure water and sewer is placed in un-serviced areas. And so that price tag alone just is not feasible,”

In June, the federal government amended regulations to give municipalities more time to reach the standard, but on cost, even big regions like Metro Vancouver, are struggling with the bill.

Its North Shore Wastewater Treatment Plant has ballooned in cost to an estimated $3.86 billion.

Authorities say it’s needed to replace old, aging infrastructure and meet the federal standards.

Teasdale’s HoldFast NL first approached Conception Bay South to suggest the seaweed solution. If there’s sufficient evidence that seaweed filters enough waste to be effective and affordable, other municipalities in the province will be interested in his company.

“Seaweed is sort of a natural biofilter that filters saltwater and takes up the nutrients and the metals and the kinds of things that are found in the wastewater,” Teasdale said.

“It’s more of a nature-based solution, rather than… big infrastructure and big concrete plants.”