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Noise sprawl threatens protected areas, critical habitats

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Lay summary of:
Noise pollution is pervasive in U.S. protected areas. Rachel T. Buxton, Megan F. McKenna, Daniel Mennitt, Kurt Fristrup, Kevin Crooks, Lisa Angeloni and George Wittemyer (May 4, 2017). Science 356 (6337), 531-533. [doi: 10.1126/science.aah4783] Online access (subscription)

Ongoing data analysis by researchers from the National Park Service and Colorado State University is revealing an increasingly detailed picture of the sprawling impact of human noise in protected areas around the United States. The most recent paper from this groundbreaking team digs into the sound models to offer a better sense of how extensive the issue is, and highlights the promise of focusing conservation efforts on preserving areas where the human noise footprint remains small.

The researchers zero in on two key thresholds of noise: 3dB above the natural ambient sound, which marks a doubling of noise levels (causing a 50% reduction in the area over which sounds can be heard), and 10dB of excess noise, which is a 10-fold increase, leading to a 90% reduction in listening area. As the authors note, these are “levels known to interfere with human visitor experience and disrupt wildlife behavior, fitness, and community composition.”

The new maps include all protected areas in the US: federal, state, and local. Not surprisingly, the “natural” areas near cities tend to be very loud (yellow on the maps below, up to 30dB of additional human noise). Read the rest of this entry »

Mt. Rainier air tour planning: a rare case of “not to late”

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At most of the places where the National Park Service and FAA have commenced air tour management planning (ATMP), there is already a deeply entrenched local air tour economy, as well as a visitor expectation that they can take flight in order to see the beauty from above.  The Grand Canyon is of course the Mother of All Overflight Controversies; similarly, the the Black Hills/Mt. Rushmore and Hawaii Volcanoes ATMPs also dove into situations where thousands of annual flights were already taking place.

But now for something completely different: At Mt. Rainier National Park near Seattle, only 114 flights are currently allowed each year, with actual numbers apparently lower.  This provides a rare opportunity to give real consideration to Alternatives that truly maintain natural quiet on the mountain.  The Park is currently accepting comments on a set of draft alternatives for use in the ongoing EIS process.  Two of the proposed alternatives would greatly reduce noise in the park backcountry: Alternative 1 simply bans all flights over the park, and Alternative 4 keeps planes to the far periphery of the park, and at high altitudes.  Alternative 3 allows 55 flights per year to circle the peak, and introduces the NPS’s recent innovation (being spearheaded at the Grand Canyon) of setting aside no-fly times – in this case, weekends, and sunrise/sunset on Monday-Thursday, and keeps planes at 2000 feet or more.  Alternative 2 maintains current use patterns around the peak, capping flights at 114 per year.

Truthfully, any of these options will maintain Mt. Rainier as a place where hikers can experience the natural soundscape with minimal intrusion.  But, the opportunity to establish a precedent for keeping commercial air tours out of relatively pristine National Park lands is one that is worth keeping on the table; we encourage support for the inclusion of the “no air tours” alternative.  Comments are being accepted through May 16.

NPS Mt. Rainier ATMP page ; Mt. Rainier Draft Alternatives

And remember, comments are being accepted through early June on Draft Alternatives at Hawaii Volcanoes National Park, too.  There, Alternatives range from 28,000 flights per year to “no air tours” (though this will allow flights around the periphery, and over 5000 feet within the park).  You can read about the process and comment here, and you can download the alternatives here.

McCain amendment aims to undercut Grand Canyon noise reduction plan

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Senator John McCain has introduced legislation that would derail the National Park Service’s recently-released compromise plan to reduce noise levels in the Grand Canyon.  McCain’s initiative, apparently included in an amendment to another bill (details are sketchy so far, with nothing on McCain’s website so far), would declare that keeping half of Grand Canyon National Park relatively free of noise from air tours is good enough.  By contrast, the NPS proposal, which increased the total number of tourist flights allowed but concentrated them in smaller flight zones, would keep two-thirds of the canyon free of any aircraft noise (including commercial jets and non-tour private aircraft) for most of the day.

McCain seeks to codify what has been the Park’s modus operandi for the past 17 years, a 50% protection standard that was achievable without making major changes.  That interim approach was adopted while Park staff, environmental groups, and air tour operators attempted to come to a consensus on how to move forward.  While the NPS does not and cannot regulate commercial overflights, the sound from high-flying jets does impact the canyon, and the NPS included these sounds in its planning of air tour routes, so as to keep aircraft noise inaudible for 75% of the day in the “quiet” parts of the park (of course, allowing aircraft noise for 25% of the day hardly creates an experience of solitude…but this is part of the compromise that wilderness advocates are being asked to accept).  By not counting commercial flights in the total noise budget of the Park, McCain is rolling things backward.

The McCain approach would also do away with two of the Park Service’s key innovations: seasonal shifts of air tour routes, so that different parts of the park are quiet at different times of the year, and most importantly, the no-fly period that would keep the canyon truly quiet for an hour after sunrise and an hour before sunset.

Ironically (or perhaps not, for those tracking the Maverick’s devolution over the past few years), McCain was the main proponent of the 1987 bill that set this process in motion, and called for “substantial restoration of the natural quiet and experience of the park.”

NPS calls for sunrise/sunset no-fly times at Grand Canyon

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CopterOverGrandCanyon copy

The National Park Service has released its proposed air tour management rules for the Grand Canyon.  Key features of the plan include increased flight altitudes near North Rim overlooks, reducing flights in Marble Canyon, moving routes away from some key visitor use areas, and establishing an hour-long flight-free period for an hour after sunrise and an hour before sunset.  This last change will be especially appreciated by backcountry hikers and river-runners, for it provides two hours a day of true extended natural quiet, at the times when the soft, rich light brings the canyons walls most subtly and dramatically alive.

The proposal caps nearly 25 years of work, initiated in the wake of a 1987 congressional mandate to come up with a plan that “provides for substantial restoration of the natural quiet and experience” of the Canyon.  The proposal would allow slightly more flights than are currently operating, but would largely concentrate them in one long and one short flight loop. The plan is now available for download and public comment through early June.  The NPS press release notes that the plan should increase the area of the park experiencing substantial natural quiet for most of the day from just over half to close to two thirds.  The objective measurement standard used by the Park Service defines substantial natural quiet to mean that in these areas, no aircraft will be audible for at least 75% of the day; so, you might hear a plane for up to one minute of every four, or fifteen minutes of each hour, though undoubtedly there will be some areas of the park far enough from the flight routes that the noise will be very faint and far less common.  Once we have time to read the full Draft EIS, it may become clearer whether there are some areas in the park that are virtually free of air tour noise (commercial airline flights regularly pass directly over the park; the plan does not suggesting shifting these routes).

The busiest year on record, 2005, saw 57,000 air tour flights provide birds-eye-views of the Canyon to over 400,000 visitors annually; the new plan would allow up to 65,000 flights annually, and up to 364 flights a day, 50 more than the busiest day on record.  Initial reactions from the National Parks Conservation Association and the Sierra Club, both of which have pushed for flight regulations, has been supportive.

Update, 2/4/11: Steve Bassett, president of the U.S. Air Tour Association, characterized the National Park Service’s recommendations for the Grand Canyon as “unconscionable” and the document as “designed to drive the industry out of existence.”  His objections are largely centered on the requirement that within ten years, all planes must be modern low-noise aircraft. He also objected to the annual cap of 65,000 flights, claiming that the annual number of “possible flights” is now 94,000 (presumably this totals all current operators, if they all flew the maximum number of flights possible per day; in fact, as noted above, the busiest year on record saw a demand for just 57,000 actual flights).

Update 2/6/11: Good article from Las Vegas newspaper, stressing the role of Grand Canyon tourism as part of what Vegas visitors want to experience, often by air.

Update 2/7/11: Good detailed post from National Parks Traveller, including longer response quotes from Park staff and conservationists.  One key piece: the plan continues the practice of allowing flights over the canyon near Hermit’s Rest, a popular spot for short hikes into the canyon:
“We had advocated that they move the Hermit flight path a little bit further to the west so that it really didn’t affect people who would take a quiet stroll down from Hermit’s Rest, down that little canyon,” said NPCA’s Mr. Nimkin. “That’s where you can sit there and every 90 seconds have a helicopter or a plane flying overhead. It would seem like that’s a pretty highly visited area, maybe one of the only times that people who are taking a shuttle out to the end of the road there would sort of stroll down into the canyon. To have that be the flight path seems inconsistent.”

See earlier AEInews coverage of Grand Canyon overflights here.

The sounds of silence at Great Sand Dunes National Park

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Repost of a column by park staff, printed in the Valley Courier, the local paper in nearby Alamosa, Colorado:

Have you ever heard the rustling sound of a bird’s wings flapping overhead…before you saw the bird? What about the sound of a rabbit chewing on a blade of grass? Most Americans don’t have the opportunity to hear those subtle sounds of nature at home, thanks to the backdrop of human-produced noises which drown them out.

Many people, however, say that the opportunity to hear natural sounds is an important reason to protect national parks, based on a 1998 study of the American public. And most respondents to a 1995 survey of national park visitors said that enjoying the sounds of nature and natural quiet were compelling reasons to visit national parks.

But-what exactly is ‘natural quiet’? Most of us would say that it’s the sounds of nature without an overlay of traffic, airplanes, machinery and other kinds of human-produced sounds. But anyone who has ever spent a windy night camping at the Dunes knows that windy nights might be ‘natural’…but they’re sure not ‘quiet’!

In order to learn just how quiet-or not–the natural world is at Great Sand Dunes National Park and Preserve, the National Park Service’s Natural Sounds Program installed a temporary acoustic monitoring station Read the rest of this entry »