Excess Salt a Potential Hazard for Shubenacadie Fish
By Zack Metcalfe
FORT ELLIS: The Shubenacadie River stands out, for the routine tidal bores which reverse its flow, for the sheer volume of fresh water it drains from central Nova Scotia, and, most importantly, for playing host to the last spawning population of Striped bass known in the Bay of Fundy.
At one time these anadromous fish ascended the Annapolis and St John rivers as well, spawning in short order before returning to the Atlantic, but causeways, turbines and other well-meaning amendments to these rivers put an end to both populations. Only the Shubenacadie remains, for the bass, the recreational fishery they support and the researchers they fascinate.
It’s into this river that Alton Gas – owned by the Alberta based AltaGas – intends to dump as much as 3,000 tonnes of salt daily in the course of coming years, an unacceptable risk to its resident bass in the considered opinion of those who study them.
“We’ve got a bit of an experiment on our hands,” said Trevor Avery, an associate professor of biology, mathematics and statistics at Acadia University who, among other things, has dedicated years to the Striped bass of the Shubenacadie River. To his knowledge, the dumping of salt in a watershed this complicated has never been attempted.
The tidal bores brought about by Fundy’s high tides push up the Shubenacadie every 12 hours, reversing its flow and turning its water brackish, even as far upstream as Alton Gas’ intended dumping site north of Stewiacke. This daily back and forth, the existence of deep pockets along the river bottom which trap or retain water, and the complex interactions between masses of freshwater and saltwater, among other oddities, all make for a watershed which is difficult to predict, and which might never fully drain.
“The river probably doesn’t flush as well as we’d expect it to,” said Avery, meaning Alton’s additional 3,000 tonnes of daily salt so far upstream has the potential to overstay its welcome, even build up to levels dangerous for native wildlife rather than proceeding downstream to the Atlantic. The truth, said Avery, is that we just don’t know what will happen, a dangerous gamble given the fragility of the river’s Striped bass.
Alton Gas intends to create 2-15 underground caverns for the storage of natural gas by hollowing out existing salt deposits. Water from the Shubenacadie River would be used to dissolve this salt into brine, which would then be pumped back into the river. While Striped bass have proven themselves tolerant of reasonably high levels of salinity in the few toxicity tests Avery’s aware of, he said the brine produced by Alton Gas would far exceed any known threshold.
Documents recently obtained from Alton Gas by Sipekne’katik First Nations water protectors – using freedom of information legislation – showed that brine released into the river could have a salinity as high as 260 Parts Per Thousand (PPT) when anything over 40 PPT is considered a “deleterious substance” (harmful or dangerous) by Environment and Climate Change Canada.
Alton Gas has constructed a short channel, open to the Shubenacadie on both sides, where they intend to dump their brine. This so-called “mixing channel” is intended to dilute the brine before it reenters the river proper, an open concept which, again, comes with no firm precedent. Whether the brine would be sufficiently diluted within the channel or without is a question Avery cannot answer. Fish have since been caught in this channel by the aforementioned water protectors.
“Adding a perturbation into the system, a change, could have profound effects we wouldn’t be able to notice for sometime,” said Avery.
The number of Striped bass spawning in this river is not known, he said, nor is the number of eggs they produce or the number of those eggs surviving into adulthood. These gaps in our understanding of a healthy population could mean its decline or crash could proceed without us taking notice in time.
Raising the Bar
Science is, by its very nature, an open pursuit, said Avery, accepting of criticism as well as collaboration. It’s exactly this transparency which is missing from the effluent pipes of Alton Gas.
“There are a lot of problems in the scientific community when things happen behind closed doors,” said Avery. “As academics, we don’t operate behind closed doors. We operate in the public forum.”
Instead of proving the safety of their work to the satisfaction of Avery and other, he said, Alton Gas has been using legal remedies to move their project forward in spite of external criticisms, a state of affairs he finds unsettling. In the end, he said, there are too many unknowns for him to be confident in the safety of his bass, a population considered endangered by the Committee on the Status of Endangered Wildlife in Canada.
“You have to go further than the bar of the law, or the bar of any environmental assessment,” he said. “Some of those bars aren’t high enough, aren’t transparent enough.”
“I don’t necessarily think we should stop these types of projects [outright], but I think we have to step back and ask, what is the benefit, and is that benefit more important than the lifeblood of our local ecosystems? If we start messing those up – and we’ve done a lot of that already – there’s no coming back.”
Zack Metcalfe is a freelance journalist, columnist and author active across the Maritimes.
MAIN PHOTO: Shown above are the Striped bass of the Shubenacadie River.
Sean Landsman photo