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2nd February 2023
EDITORS NOTE: This article sounds as familiar as the name Cassidy Aquifer! Please take the time to read this article and then to understand why we are doing the fight to Save the Cassidy Aquifer.

City of Prince George needs to protect Lower Nechako River Aquifer

Opinion: As a shallow, unconfined aquifer, any large spill of hazardous material could cause contaminants to seep down through the sands and gravels to poison our water for years or even decades.

Author of the article:Dave Tamblyn, Special to the Prince George Post
Published Jan 30, 2023

Access to safe drinking water is now recognized as a human right, fundamental to everyone’s health, dignity and prosperity.

A right to safe water goes together with a right to safe sanitation. The United Nations monitors global progress under its Sustainable Development Goal 6 — water and sanitation for all. The right to water entitles everyone to access to sufficient, safe, acceptable, physically accessible, and affordable — not free — water for personal and domestic use.

Everyone has heard that “water is life.” But groundwater doesn’t get the public appreciation it deserves — out of sight, out of mind? Almost every Prince George resident can name the two rivers whose intersection give our host First Nation its name (Lheidli means “people from the confluence of the river” in Carrier). But how many know the name of the aquifer that supplies our drinking water?

The City of Prince George has been fortunate in avoiding boil water advisories. Part of Prince George’s good fortune in water supply is founded on geology, and specifically hydrogeology — the study of the distribution and flow of groundwater in soils and rocks.

It may seem odd that Prince George uses groundwater as a water source, rather than the abundant surface water flowing in our mighty rivers, but that choice is justified in terms of both public health and economics. Those great rivers carry a substantial load of fresh sands and gravels that have accumulated over thousands of years to create a thick, productive, safe aquifer underlying the city.

An aquifer is sometimes described as an underground river or lake, but a better analogy may be a half-empty Slurpee: you can drink it, but it takes some work. The gravels along the Nechako River from Miworth to the confluence with the Fraser River are especially productive, meaning wells can supply a lot of water with minimal pumping.

The city wells that tap into this aquifer are constructed with a central concrete shaft fed by horizontal radial wells. This special “collector well” design makes Prince George’s water supply wells among the most productive in North America. Incredibly, two of Prince George’s three collector wells could each supply a city of over a million people by themselves.

Of course, the quantity of water matters little unless the quality is acceptable. The Drinking Water Protection Act defines potable water as “safe to drink and fit for domestic purposes without further treatment.” The water from the collector wells is potable, without any treatment.

“Safe to drink” is a challenging target to hit. Health Canada specifies health-based guidelines for 56 physical and chemical parameters, — covering both things you’ve likely heard of such as lead and copper; and things you’re unlikely to ever hear of such as perfluorooctane sulfonate. In addition, there are 19 esthetic parameters, five microbiological parameters and 11 radiological parameters. To achieve potability, a groundwater source has to pass up to 90 tests!

Safety is also a moving target, as cities such as Quesnel know all too well. Health Canada reviews about three water quality parameters each year to assess and possibly revise its guidelines in light of new scientific findings. In 2019, the long-standing esthetic objective for manganese — a common mineral that is actually essential for human health — was lowered and a health-based guideline was added.

Several of Quesnel’s wells exceed the new guideline. Some of Prince George’s older wells would have exceeded too, but the newer collector wells pass the test.

Another parameter that causes serious problems in the North is arsenic. Many municipal water systems had to add treatment when the arsenic guideline was lowered in 2006, and it is once again under review.

The Lower Nechako River Aquifer covers both banks of the Nechako River starting near Miworth, all of the Bowl, and parts of the Fraser River from Shelley Road in the north to Cowart Road in the south. As mentioned, it is both productive and healthful, but also vulnerable.

As a shallow, unconfined aquifer, any large spill of hazardous material — say, a train derailment or overturned tanker truck — could cause contaminants to seep down through the sands and gravels to poison our precious water source for years or even decades.

What would the cost be if we lost our aquifer and had to switch to a surface water source? An accurate answer would require proper engineering studies, but we can get an idea by looking at Kamloops, whose river water treatment plant cost $48 million in 2005 — about $120 million today. That’s just design and construction; a surface water source requires expensive operating costs for filtration and disinfection to satisfy health requirements — adding another roughly $1.5 million per year. This implies a present value of about $170 million for our aquifer.

Whatever the exact amounts, it’s clear that the Lower Nechako River Aquifer is a valuable asset for the municipal government. In addition to the water supply for people, aquifers provide valuable ecosystem services, supporting groundwater-dependent ecosystems such as fens, which provide wetland habitat and also sequester carbon to help combat climate change.

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Aquifers store water during wet periods and release it during dry periods, maintaining river habitat vital to aquatic fauna. “Base flow” from aquifers keeps rivers flowing — and cool — even when precipitation is absent for long periods. This buffering service will become even more vital in the coming decades as glaciers retreat or disappear. Without aquifers, the Nechako likely couldn’t support salmon or sturgeon.

How does the $170-million value of the Lower Nechako River Aquifer figure into the city’s balance sheet? It doesn’t, yet.

And so, the city and its citizens pay scant attention to preserving and protecting it. In 2014, Gibsons, B.C., population 4,400, became the first municipality in North America to pass a municipal asset management policy that recognizes its aquifer as a natural asset and creates specific obligations to operate, maintain and replace natural assets alongside traditional capital assets. Prince George should follow suit.