The illegal 35 million gallon wastewater discharge in the Gallatin River has stopped, but the larger issues of how Big Sky grows and addresses wastewater, stormwater, and landscape pollution remain.
Update 1: The Spill Has Stopped
As of early Monday, March 8th, Yellowstone Club’s defective wastewater pond was pretty much empty and, likewise, illegal discharges into downstream creeks pretty much stopped. Emptying the wastewater pond was, unfortunately, necessary to access the broken pipe and faulty liner which together appear to have caused the entire pollution release.
Investigations of the drained pond revealed ice likely broke a key pipe. Engineers think that once the pipe broke, the pressure of millions of gallons of wastewater tore the pond’s liner and created a torrential, unrestrained discharge of up to 500,000 gallons per hour.
Do the math and it all works out to about 35,000,000 gallons of wastewater discharged. That number fits with press releases from the Big Sky Water & Sewer District, saying approximately 30,000,000 gallons was from the District, and 5,000,000 gallons was from the Club.
The unique, confined geography and small dilution capacity of (historically clean) creeks of the greater Big Sky area, combined with strict limits on wastewater discharges, means the Yellowstone Club and the local Sewer District struggle to dispose of millions of gallons of wastewater during winter months.
As this terrible accident illuminates, there needs to be a broader inquiry into how Big Sky and resort areas are handling wastewater, intense development, and protecting the local environment.
Update 2: What We Know (Science)
Waterkeeper was on the scene Thursday evening to take initial water samples of the pollution spill. We took samples to, first, confirm in fact there was a wastewater spill and two, to better understand how severe a pollution event to expect. Wastewater, even the kind treated for re-use, contains unnatural levels of nitrogen, phosphorus, E.coli and dissolved oxygen, not to mention other pathogens that conventional treatment doesn’t address.
If wastewater’s nutrient levels were high, there could be a threat of toxicity to downstream waterways and fish. Thankfully, nutrient levels and chlorides (another by-products of treatment that can be toxic in high quantities) were all below risk levels. E.coli levels were unnaturally elevated, but not enough to create a health risk.
We – and other stakeholders like Gallatin River Task Force and state DEQ – are awaiting lab results on Biochemical Oxygen Demand (BOD), which is a calculation of available oxygen in a water column. Just like humans breathe air, so too do aquatic communities need certain levels of dissolved oxygen to breathe. Wastewater treatment can lower available oxygen levels and, when added to waterways with small dilution capacity, threaten local fish and other critters.
- Click here to view Waterkeeper’s initial pollution event sampling data.
- Click here to view other monitoring data.
- If you are a local riparian landowner and are concerned about impacts to your well, you can obtain a free test kit from the local watershed folks – Gallatin River Task Force – by clicking here.
On the other hand, the discharge of ~35 million gallons of wastewater picked up unknown pounds of sediment, turning the S. Fork, W. Fork, and mainstem Gallatin murky brown. Turbidity and suspended sediment can create direct and indirect threats to local fisheries. Science clearly shows that dramatic increases in suspended sediment can suffocate fish, wipe out food sources, smother substrate, negatively affect spawning and young-of-year, harm immune systems and increase the risk of predation.
DEQ’s sampling showed extremely high turbidity levels in all impacted waterways. State water quality standards prohibit discharges that create anything above a 5 NTU increase beyond natural background levels. Specifically, Second Yellow Mule Cr., the S. Fork and the W. Fork all saw turbidity levels hundreds of NTUs higher than natural background.
Put another way, sediment levels were extremely high and that doesn’t bode well for local, low-flow/low-dilution capacity of winter condition waterways.
Update 3: What We Don’t Know (Impacts & the Big Picture)
With wastewater discharges pretty much stopped, and preliminary data in, the outstanding questions are two-fold. (1) What will be the impact on local fisheries? (2) How do we make sure something like this never happens again?
At this time all we can offer is an educated guess on fisheries impacts. We still don’t have important oxygen data on the wastewater, although we do know harmful levels of sediment have been circulating and suspended in many creeks and the mainstem Gallatin’s water column for over 72 hours. Fish science says we need to do physical surveys of affected waterbodies to look for any fish kills after waters clear later this week, as well as look to FWP for fish population estimates.
Brown trout young-of-year run a high risk of at least being threatened as they’re the youngest fish class in local waterways. On the other hand, with so much sediment in waterways substrate health is likely down being smothered with sediment, which could affect this spring’s rainbow spawning and redd viability. Spring runoff probably won’t clear the rivers before rainbow spawning.
Just because the Gallatin and its tributaries narrowly avoided a bullet here by not seeing toxic nutrient levels or raw sewage doesn’t mean we should brush this event under the rug. Rather, this event is a call-to-action for everyone who cares about the Gallatin to start asking hard questions about whether the status quo is serving our rivers and the important economy and communities they support.
Big Sky’s rapid growth in recent decades has inspired many critical news articles, and rightfully so. The Yellowstone Club’s founder infamously broke environmental laws by illegally backfilling wetlands and creeks, building in sensitive riparian areas and installing unlicensed septic systems.
While Mr. Blixeth’s corporations were later held accountable for these egregious violations, the modus operandi of “easier to ask for forgiveness and pay a fine than ask permission” is still a force to be reckoned with. The greater resort area has similarly transformed forested hillsides into impervious parking lots, mowed down meadows for condos, and generally played catch-up in terms of building and development codes.
In 2015 two expert engineering reports examined the exact issue behind the Yellowstone Club wastewater spill: wastewater treatment and disposal in the greater Big Sky area. Findings from those reports and evolving water science is very important to framing the broader picture of waterway health in Big Sky and the Upper Gallatin:
- Local Big Sky creeks are already impaired for unnatural, unhealthy levels of nutrients and sediment loading. The dramatic landscape transformation associated with the resort and communities’ intensive build-out in the region’s three river valleys are primary causes of local waterway impairment.
- Moonlight Basin, Spanish Peaks, the Yellowstone Club, and Big Sky Water & Sewer District wastewater disposal and treatment are nearing capacity and limits of existing treatment. The Big Sky area needs to address wastewater disposal and infrastructure upgrades in the near future.
- Limited, sporadic enforcement of stormwater pollution controls in conjunction with severely degraded riparian zones and widespread conversion of forests and meadows is contributing to local water quality problems. The Big Sky area needs to reevaluate development through the lens of stormwater pollution and riparian zone protection.