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NPCA Officials Cite Snowmobile Emissions In Criticizing Winter-Use Plan For Yellowstone National Park


Pointing to the National Park Service's own testing as evidence, National Parks Conservation Association officials are criticizing a proposed winter-use plan for Yellowstone National Park, saying testing shows snowmobiles have gotten dirtier and noiser, not cleaner and quieter.

In pointing to the park's Yellowstone Over-snow Vehicle Emission Tests – 2012: Preliminary Report, NPCA officials say the trend to dirtier and noiser snowmobiles the past six years "contradicts the snowmobile industry’s repeated promises to make cleaner snowmobiles and keep unhealthy gasses such as carbon monoxide, benzene and formaldehyde from fouling the air of the country’s oldest national park."

The report explains that scientists tested 2011-model snowmobiles in Yellowstone and compared their emissions with 2006 models made by the same companies, NPCA noted in a release.

"One manufacturer’s newer snowmobile emitted over 20 times more carbon monoxide than its earlier model. Another company’s newer model had higher emissions of every exhaust gas sampled, including 5 times more hydrocarbons," the release said.

The report concludes: “The model change in snowmobiles has not been a positive influence on air quality based on the emission data.”

In releasing the park's Draft Supplement Winter-Use Environmental Impact Statement earlier this month, Superintendent Dan Wenk said his proposal to allow up to 480 snowmobiles a day in Yellowstone, more than twice the average entries of recent winters, would make the park “cleaner and quieter.”

However, the National Park Service’s own studies contradict that assertion, the NPCA release said. "That document shows the proposed plan would increase snowmobile noise and pollution in Yellowstone National Park with significantly greater emissions of carbon monoxide and cancer-causing gasses such as formaldehyde and benzene," the park advocacy group said.

“Rewarding a technology that is going backward and getting dirtier is the very opposite of stewardship that Americans expect and deserve in Yellowstone National Park,” said Tom Kiernan, NPCA president. “After 10 years of pledging to make major improvements to emissions and noise, the snowmobile industry has gone back on its promise to the National Park Service and the public."

The emissions study looked at “recent additions to the snowcoach fleet” and concluded: “emissions are generally lower for newer snowcoaches compared to mean values of the earlier fleet and especially compared to the older carbureted engine snowcoaches.”

Indeed, specific data provided in the report show that current snowcoaches are up to 50 times cleaner than current models of “Best Available Technology” snowmobiles when the vehicles’ carbon monoxide emissions are calculated on a per-visitor basis. In per-visitor emissions of hydrocarbons and nitrogen oxides, the report shows snowcoaches are 2-5 times cleaner than snowmobiles. The report reflects that these air-quality advantages of snowcoaches are expected to become even more significant when Yellowstone requires all snowcoaches to utilize newer engines.

“The National Park Service should make an immediate U-turn on this misguided policy. After all, the growing majority of Yellowstone Park’s visitors prefer multi-passenger snow coaches, which are demonstrably cleaner than snowmobiles, which are getting dirtier. Even park officials have acknowledged that,” said Chuck Clusen, director of the National Park Project at the Natural Resources Defense Council. “The only obvious and responsible path forward is to facilitate the use of snow coaches, not snowmobiles.”


Even if they were electric someone would sue to remove them... that is how lawyers make money and how the park system loses money.

This is an example of how the orthodox Wilderness movement's opposition to bicycles on trails is fundamentally counterproductive. I've read that 0% of Yellowstone is Wilderness and that's why the snowmobiles can operate in it. With mountain bikers on their side, Wilderness advocates would have a better chance of getting Congress to designate parts of Yellowstone as Wilderness. Thus doth the perfect get in the way of the good. Meanwhile, the blanket bicycle ban on Wilderness means that thousands of miles of Wilderness trails that cyclists would ride and help maintain are falling into abandonment from nonuse. Was there ever a more misguided approach to this issue?

Don't take it from me. Take it from the National Park Service itself. Quote: "Congress must take the opinions of all American citizens into consideration when debating whether or not to designate an area as wilderness. As you might expect, this process can take years, even decades. For example in the National Park Service, recommendations dating back to the late 1970s still exist for 13 national parks, three national monuments, and one national seashore. This is why some lands that have been recommended to Congress have been designated as wilderness and some lands, such as areas in Yellowstone and Glacier National Parks, have not."


I hear that there's new leadership at the top of the Wilderness Society. It might be time for it to take the plunge and forge an alliance with mountain bikers. The quid pro quo—support for new Wilderness in exchange for supporting mountain bike access to trails few people ever visit—seems worthwhile to me.

imtnbke, welll, not all mountain bikers approve of wilderness because under current rules bikes are not allowed in officially designated wilderness. But you know that. And you've argued against that as well.

From IMBA's point of view, that organization believes "that cross-country (XC) style mountain biking is an appropriate, quiet, muscle-powered activity that belongs in Wilderness alongside hiking and horseback riding."

Now, I'm not sure what "cross-country style mountain biking" is, but it sounds like off-trail, though I might be wrong. Perhaps Mark could wade in and explain??

But to the general issue of when Yellowstone will see officially designated wilderness, that will not happen as long as Wyoming's congressional delegation opposes it. And as to the NPS taking the opinions of all Americans into consideration, last I heard the percentage of American citizens who commented on the Yellowstone winter-use plan and who wanted to see snowmobiles phased out was about 80 percent. And NPS officials are quick to point out that public comments "are not a vote."

All that said, technology exists to provide cleaner, and quieter, winter recreation in Yellowstone, whether that's in a snowcoach or snowmobile. The park's own tests prove that.

Hi, Kurt — That, of course, is my point. The Wilderness expansion proponents, whether interested in National Parks or National Forests, have to slog uphill all the time, and mountain bikers' opposition to losing valued trails when an area becomes Wilderness makes the slog just that much harder. I'm sure you're right, though, that mountain bikers' support for Wilderness would not magically transform Yellowstone into Wilderness overnight, or even in five years. I'm not arguing that. It's other places that lack the Wyoming congressional delegation that might benefit from the conservation equivalent of what is called in Italian history the compromesso storico (historic compromise).

One would hope that the Wilderness Society and the Sierra Club would rethink their stance, but I'm skimming today's New York Times and just saw this headline: "Gay People Will Remain Unaccepted by Boy Scouts." It's a reminder that organizations are capable of sticking mule-headedly to antiquated and self-defeating dogmas. Perhaps the Wilderness folks can do better than the Boy Scouts in reflecting on the wisdom of past stances. After all, in 1978 the Church of Jesus Christ of Latter-day Saints wisely decided that black people do not bear the "Curse of Cain" and can be accepted into the church's priesthood! And that in turn is allowing Mitt Romney to run for President.

I can answer your question about cross-country. Mountain bikers like to stick to trails, which makes us unlike some hikers. All that cross-country (XC) means is mountain biking on trails that involves a lot of climbing and physical effort, as opposed to downhill (DH), in which the aim is to go from a high point A to a low point B, often aided by a motor vehicle shuttle. The downhill crowd isn't interested in Wilderness or National Park access—the trails are likely to be too physically demanding. Some of those guys (and the occasional gal) aren't in very good shape.

I don't care what you are trying to prove but I will still take winter over summer for less noise and less emissions from vehicles as a person trying to enjoy Yellowstone.

Secondly you say the snowmobiles are getting dirtier. Maybe they do have higher emissions but look at what the manufacturers have done with the snowmobiles. They have gone from 40 hp in the early ones that the consumer doesn't desire to now producing 130-180 hp that the consumer now will accept for other places other than Yellowstone thereby helping improve emissions in other places that only had a history of 2 stroke engines. You act like it is a bad thing to have cleaner engines everywhere that will help in areas outside Yellowstone also. There hasn't been a clear limit of snowmobiles allowed in Yellowstone for several years so the manufacturers have to make something that will appeal to the consumer to want to buy besides just supplying snowmobiles for Yellowstone. They are still meeting the Best Available Technology requirements and selling all over the world those same snowmobiles too now that they have refined them.

Go and enjoy Yellowstone in the winter and see and respect what it has to offer.

YNP4everyone — I know you're writing to Kurt, not me, but I have a question. I don't know much about snowmobiles. Are electric ones technologically feasible? I assume they'd be as quiet as a Prius as well as pollution-free, and that might make them more acceptable to people who don't like them. Just curious.

YNP4everyone, can't disagree with you re the wonders of Yellowstone in winter and the less congestion when compared to summer. It is a great experience, and I've been lucky enough to sample it twice so far.

As for snowmobile emissions, according to the park's own data (Ch 3 of the latest DSEIS, page 114), in 2002-03, when two-strokes ruled the roost and there were hundreds more snowmobiles allowed in the park, maximum CO emissions per 8 hours was 1.2 parts per million. In 2009-10, when BAT was supposed to have been onboard, those emissions rose to 1.7 ppm, before dipping back to 0.9 ppm for 2010-11.

And according to Yellowstone's own studies, the snowmobile fleets are not meeting BAT requirements.

imtnbke, some years ago, around 06 or 07 I think, a Utah company built a prototype electric snowmobile that their studies claimed was as powerful as a two-stroke.

Now, why the manufacturers didn't jump on board, I don't know, but it apparently can be done.

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