WC148 MayJune 2026 - Magazine - Page 28
ENVIRONMENT
Under the Microscope
Water quality of great concern when it comes to
Ontario’s nuclear ambitions
BY WARREN FREY
UCLEAR POWER’S PROFILE has surged in
recent years as a possible source of green power.
But is nuclear sustainable when it requires massive amounts of water to function?
The province of Ontario is looking to build one
of the biggest nuclear power stations in Canadian history
near Port Hope, Ont., but one expert warns the province’s
largest source of freshwater could be at risk.
Swim Drink Fish founder Mark Mattson has voiced concerns on his Substack about the long-term effects of nuclear
mega-projects on the flora, fauna and overall water quality
of the Great Lakes.
Mattson said he has been involved in energy issues since
the early 1990s as one of the counsels for the Nuclear
Liability Act’s constitutional changes and counsel for the
Ontario Energy Board during Ontario Hydro reviews. He
also served as executive director of the Environmental Bureau of Investigation in the 1990s, a non-profit established
to investigate pollution and enforce environmental laws.
“It seemed after the last big push in the early 1990s
where Ontario said they needed to double their nuclear
capacity by 2020 with a 25-year plan or we’d be freezing in
the dark, that hearing went two and a half years and at the
end of it, we didn’t get a decision,” Mattson said.
The numbers and evidence surrounding nuclear power
had changed during the hearing to such an extent that the
Ontario government withdrew the proposal “and nothing’s
been built since,” he said.
Recent announcements by the Ontario government
about extending the life of existing nuclear facilities, building small reactors and new larger facility have created a new
wave of enthusiasm for nuclear power, Mattson said, but
there are issues to consider regarding water quality, especially regarding the Great Lakes.
But while nuclear power is touted as a way to reduce
greenhouse gas emissions, he said, many of the components
of a plant either produce emissions or require environmentally harmful chemicals to operate.
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“These are huge turbines that need all kinds of lubrication,
backup power and diesel engines. They’re huge operations and
it’s not just splitting the atom,” he said.
Mattson added while American reactors have largely moved
on from older, less efficient cooling technologies, Canada
still uses a system that consumes an enormous amount of
freshwater.
“We’re concerned about the Canadian technology (being
used) because it takes for granted the quantity and quality of
water that they’ll have access to from Lake Ontario and Lake
Huron,” Mattson said.
The Canadian systems use a process called ‘once-through
cooling’ which is illegal in the United States, he said. Instead,
US plants use cooling towers and closed-cycle cooling where
the same water is recycled to cool reactors rather than drawing
on an outside source.
“Once through means you’re just sucking constantly from
the lake and spitting it out and the amounts of water are huge”
Mattson said. “When you’re bringing it in from the lake,
you’re sucking in fish, eggs, embryos and trapping them in
screens and then the water goes back out at really high tem-
WAT E R C A N A D A . N E T
OPG
Warren Frey is
Associate Editor of
Water Canada.
The province of Ontario is looking to build one of the biggest nuclear
power stations in Canadian history near Port Hope, Ont., but one expert
warns the province’s largest source of freshwater could be at risk.
