After more than three decades of mounting concern, there are finally signs of improvement on water pollution from metallurgical coal mining in B.C.’s Elk Valley.
Elk Valley Resources, the mines’ owner, now has four water treatment facilities operating, and for the first time in decades, selenium levels are no longer rising. But the Elk Valley’s water pollution problem is far from resolved, and it likely won’t be for many decades.
Industry and its proponents regularly boast that water treatment facilities are removing 95-99% of selenium from treated water. While this may be true, it only applies to water that flows through treatment facilities. The majority of mine-produced selenium still flows down these rivers untreated.
Treating all affected water remains a long way off
In 2024-2025, the Elk Valley treatment facilities removed 46% of mine-produced selenium from surface water (water that flows above ground in creeks, rivers, lakes, etc.), based on our estimates from publicly-available data.
Daily flow rates in the Elk and Fording rivers are heavily influenced by snowmelt and vary a lot depending on the time of year. Water treatment facilities operate most effectively in the fall and winter when there is less water flowing down the river because this allows them to treat a higher overall percentage of mine-impacted water.
In May last year, when water levels were high, they only treated 22% of the Elk River’s selenium load. Their best month was January when they reached 68% removal because low water levels and precipitation allowed them to treat more of the total water going through the system.
Groundwater flow and selenium levels is a giant unknown in these equations, due to limited access to Elk Valley Resources’ groundwater data and movement models. Suffice to say, treating all the surface and groundwater that hits the mine’s enormous footprints would be a monumental task.
Selenium levels still dangerously high
So, how is treatment actually impacting overall selenium concentrations? By Elk Valley Resources’ own admission, “selenium and nitrate levels remain elevated in the Fording River and areas close to the mines.”
Selenium pollution is especially concerning, as it can build up in aquatic food chains, causing reproductive issues in fish like the threatened Westslope Cutthroat Trout, as well as in the aquatic insects these fish prey upon.
The BC Aquatic Life Guidelines, which are designed to protect all aquatic life, suggest that selenium concentrations shouldn’t exceed 2.0 micrograms per litre (ug/L). Concentrations in the Elk River haven’t been below that since 2009 (Elk River Alliance). In 2025, levels in the Fording River peaked at 30 times the aquatic life standard.
Downstream of the mines, selenium concentrations average 10 ug/L, but have reached as high as 674 ug/L (2020) at certain monitoring sites. A very small portion of this (0.4-1.25 ug/L, according to monitoring by the Elk River Alliance) is naturally occurring — the rest is entirely industry produced.
Data gaps and transparency issues
Elk Valley Resources’ data transparency is a serious issue that makes it difficult for the public to assess progress. The BC Government’s Elk Valley Water Quality Hub has made commendable strides forward in data transparency. However, the new current conditions page reads more like something from Elk Valley Resources’ public relations handbook than an impartial hub for water quality data.
The last published quarterly update, for January-March 2024, showed that selenium levels exceeded aquatic life guidelines at all times in three out of the four chosen order stations. In eight instances, selenium and nitrate levels even exceeded their discharge permits, which are far more lenient than BC’s aquatic health guidelines.
While writing this blog, the Elk Valley Water Quality Hub’s quarterly updates were discontinued. It is unfortunate to see these easily accessible summaries fall by the wayside. If Elk Valley Resources and the provincial government want to demonstrate a real commitment to transparency, they should continue timely and publicly-accessible reporting, and perhaps most importantly: open access modeling.
Plans for the future
New water treatment facilities and expansions of existing facilities are planned. These promise to increase treatment capacity, and reduce the amount of mine-produced selenium going downstream.
While this is cause for hope, it’s still concerning to see industry relying on long-term water treatment as a fix for problematic mining practices. Selenium pollution in the Elk Valley stems from the natural weathering of waste rock piles. As coal mining in the Elk Valley expands — both from new mines and the expansion of existing ones, like the proposed Fording River Extension — so too do the waste rock piles.
A long-term liability for taxpayers and the environment
Each water treatment facility will need to be maintained and operated for decades, if not centuries. An independent Wildsight-commissioned report estimated that $6.4 billion would be necessary to implement the Elk Valley’s water quality plan. This does not include the full cost of operating and maintaining treatment facilities far into the future.
The Elk Valley mines are by far B.C.’s biggest mining-related environmental liability. They account for nearly half of the entire province’s mine bonds (Appendix B), and our independent report estimated that these bonds are still billions of dollars short of sufficient.
B.C. has a history of allowing miners to disappear once operations are no longer profitable, leaving taxpayers holding the bag. Every new mine extension and expansion granted to these operators is a debt that will have to be paid by future generations.
Conclusion
The narrative of “95-99% selenium removal” refers only to the water that passes through treatment facilities, and downplays the fact that the majority of selenium leaching from these mines goes untreated.
Industry and government have been aware that runoff from Elk Valley coal mines contains dangerously high levels of selenium, nitrate and sulphates since 1995. When selenium concentrations are still hitting 30 times BC’s aquatic safety limits, the problem isn’t solved; it is being managed less poorly than it has in the past.
For the threatened Westslope Cutthroat Trout, aquatic insects, and all communities downstream, a slowing of mine pollution is not the same as a clean river. While progress has been made, it is clear that much more has to be done.