Dead fish: What Canadians could learn from the US about cooling water

“And just out of interest, looking back as the plants have been in operation for some decades now, why are we looking at this particular issue in the last decade of its life?”

That was the question posed to Ontario Power Generation [OPG] staff by Dr. Christopher Barnes, a member of the Canadian Nuclear Safety Commission. We were talking about dead fish at last May’s hearing into whether the Pickering A Nuclear Power Plant should be relicensed. Dr. Barnes wanted to know why OPG has only now begun to consider how to stop killing millions of fish at the forty-year old facility, when the plant is scheduled to be shutdown in ten years. He asked how OPG could have been unaware of the problem when they have been clearing their intake screens of dead fish for years.

Many nuclear power plants - including the Pickering and Darlington plants on Lake Ontario - kill fish in the millions each year because they use once-through cooling systems. In once-through cooling systems, water is pumped from a source, like Lake Ontario, via large water inlet channels directly into the plant. After passing through heat exchangers or condensers, the water is sent back into the lake at a much higher temperature.

A recent report prepared for Lake Ontario Waterkeeper by cooling water experts Pisces Conservation shows that once-through cooling water systems are the most environmentally damaging of all possible cooling technologies. Fish are killed in large numbers when they are sucked against intake screens. Fish eggs are sucked into the plant and killed. Other fish die or get sick when they swim in or out of the superheated water discharged from the plants, or when the heated water disappears during plant outages. We at Lake Ontario Waterkeeper first learned about the impacts of once-through cooling water from our fellow Waterkeeper organizations and lawyers such as Reed Super, who have been battling fish kills all over the U.S. for years.

In response to Dr. Barnes’ question, OPG staff said that they have always known about the fish kills. They explained that it is only becoming an issue now because expectations with respect to fish are changing in United States. New standards and legislation in the U.S. to address the impacts of once-through cooling are changing the way companies can operate in Canada.

One example of how the U.S. is leading the way on cooling water is happening in New York State, right on the other side of Lake Ontario. A coalition of environmental groups represented by the Eastern Environmental Law Centre is leading an effort to see a number of large old power plants in New York get rid of once-through cooling. The group includes the Citizens Campaign for the Environment, the Network for New Energy Choices, the Natural Resources Defense Council, and the American Littoral Society.

These groups are asking the government to require modern closed-cycle cooling in all power plants. The change could save 93 to 98 percent of the aquatic organisms killed by once-through cooling systems and greatly reduce the amount of hot water spat back into lakes, rivers, and the ocean. The group has even done a study to confirm that requiring old plants to upgrade would not interrupt the supply of power in New York and would likely result in less than a one percent increase to electricity bills.

So far, it looks like the group has support from the Department of Energy Conservation [DEC] in New York. The DEC released a draft policy in March that, if finalized, will identify closed-cycle cooling as the Best Technology Available for cooling water.

Waterkeeper is going to support our friends in New York as they move closer to getting destructive once-through cooling phased out for good. In the meantime, we’re hoping that now that decision-makers in Canada have finally noticed all the dead fish, they will start taking real steps to catch up with our southern neighbours.