[trestle]

[trestle]

[cdestroyer]

SKI; off on another tangent again? Why just take a part of the post for your observation when the post also contained other areas besides around an airport,,,,or target range/foundry. I remember many years ago when there was a fire in the pasayten and the fire fighters had to parachute in but could not get permission to use a helicopter to retrieve their gear. Noise?

[Ski]

tangent? I don't think it's reasonable to try to play "connect the dots" between the ambient noise from a commercial international airport in an urbanized area to the noise one would hear out in the woods. The impacts of high-decibel noise on wildlife are well documented - see the papers on the Whidbey Island Naval Air Station proposals - I get that part of it and I'm not in disagreement on that point. But trying to connect the kind of eardrum-shattering noise from an aircraft's jet engine with that noise level generated from a motorbike, snowmobile, or chainsaw is really a stretch, particularly when those sounds are not being generated 24/7, 365 days a year.

[treeswarper]

[cartman]

I've never had a negative encounter with a snowmobiler, ORV, dirt biker or mtn biker on a back road or trail. They've always been in places I don't actually consider true "wilderness", and so weren't unexpected or bothersome. As far as noise pollution affecting wildlife--tough. People are going to go into the backcountry, and some of the things they do make noise. As long as they are following the law and not being rude to other humans, so be it.

[drm]

[cdestroyer]

Noise in the National Parks The National Park Service manages 84 million acres of land spread across 397 national parks, 40 national heritage areas, and 582 national natural landmarks, all of which are collectively termed “national parks” in this report. The Park Service has the most wilderness acreage of the major wilderness management agencies (the others are the Fish and Wildlife Service, the Bureau of Land Management, and the Forest Service). It is also the only federal land management agency with a mandate to protect the acoustic environment, said Karen Trevino, chief of the Natural Sounds and Night Skies Division, one of eight divisions of the Natural Resource Stewardship and Science Directorate in the Park Service. “The mission [of our division] is to work to restore, maintain, and protect acoustical environments and naturally dark skies throughout the national park system,” she said in her introduction to the workshop’s opening plenary session. “We work in partnership with parks and others to increase scientific understanding and inspire public appreciation of the value and the character of undiminished soundscapes and star-filled skies.” The Park Service management policy has wording specifically dedicated to preserving the soundscape. The policy defines the soundscape as all natural sounds occurring in parks, the capacity for transmitting those sounds, and the relationships among natural sounds. Such sounds can be transmitted through air, water, or solid material and may fall outside the range of human perception. The goal, Trevino said, is not only to preserve existing soundscapes but also to restore those that have been degraded and prevent further damage. In addition, the Park Service aims to protect culturally appropriate sounds, such as music at the New Soundscape Management in the National Park Service NPS Soundscape Management Policy 4.9. According to this section of the 2006 NPS Management Policies, “Using appropriate management planning, superintendents will identify what levels of human-caused sound can be accepted within the management purposes of parks…. In and adjacent to parks, the Service will monitor human activities that generate noise that adversely affects park soundscapes, including noise caused by mechanical or electronic devices. The Service will take action to prevent or minimize all noise that, through frequency, magnitude, or duration, adversely affects the natural soundscape or other park resources or values, or that exceeds levels that have been identified as being acceptable to, or appropriate for, visitor uses at the sites being monitored.” NPS Cultural Soundscape Management Policy 5.3.1.7. This section of the 2006 Management Policies states that “The Service will preserve soundscape resources and values of the parks to the greatest extent possible to protect opportunities for appropriate transmission of cultural and historic sounds that are fundamental components of the purposes and values for which the parks were established.” NPS Director’s Order #47: Soundscape Preservation and Noise Management. This order “directs park managers to (1) measure baseline acoustic conditions, (2) determine which existing or proposed human-made sounds are consistent with park purposes, (3) set acoustic management goals and objectives based on those purposes, and (4) determine which noise sources are [adversely] impacting the park and need to be addressed by management.” Orleans Jazz National Historical Park and military sounds at national battlefield parks. The mandate extends to all sounds in and adjacent to the national parks, so sounds outside official boundaries are still of concern. The NPS wilderness policy authorizes the use of motorized equipment or mechanical transport only if it is determined by the superintendent to be the minimum required to achieve the purposes of the area, including the preservation of wilderness character and values, or in emergency situations such as search and rescue, homeland security, or law enforcement. The Wilderness Act, which is distinct from legislation governing the national parks, is also concerned with soundscapes. Park managers are responsible for making and implementing decisions about which sounds contribute to the park and which may hinder the visitor experience. “Many park visitors have certain expectations regarding the sounds they will hear,” Trevino explained. “Natural sounds such as waves breaking on the shore, the roar of a river, and the call of the loon form a valued part of the visitor experience. Conversely, the sounds of motor vehicle traffic, an electric generator, or loud music can greatly diminish the serenity of a visit to a national memorial, the effectiveness of a park interpretive program, or the ability of a visitor to hear a bird singing its territorial song.” NOISE GENERATED IN THE NATIONAL PARKS Park-generated noise can be broadly divided into the three categories of transportation, facilities and maintenance, and construction discussed by the breakout groups, explained Frank Turina, program manager for policy, planning, and compliance in the NPS Natural Sounds and Night Skies Division. The survey of park superintendents that prompted interest in holding the workshop revealed that many sources of noise in parks are associated with park operations and maintenance. Similarly, many NPS staff requests for assistance involve problems with noise. The extensive networks of bridges, trails, structures, and roads throughout the national parks require constant maintenance. Noise from buildings, such as that generated by heating, ventilation, and air conditioning (HVAC) systems, often affects the outdoor environment. Transportation by park vehicles and by vehicles supporting concessionaires generates noise. Landscaping, trail maintenance, mowing, and snow removal all contribute to noise levels. “We need to focus inwardly and take a look at the kind of noise that the parks themselves are generating, and to develop some tools and guidance for parks to help them Wilderness Act and NPS Policies Governing Noise from Motorized Equipment in the National Park Service Wilderness Act 36 CFR Section 2.12 Audio Disturbance. Under this section the following is prohibited: Operating motorized equipment or machinery that exceeds a noise level of 60 decibels measured on the A-weighted scale at 50 feet or, if below that level, nevertheless makes noise that is unreasonable. Wilderness Act 36 CFR Section 2.18 Snowmobiles. Under this section, “Snowmobiles are prohibited except where designated and only when their use is consistent with the park’s natural, cultural, scenic and aesthetic values, safety considerations, park management objectives, and will not disturb wildlife or damage park resources.” The following are also prohibited: “Operating a snowmobile that makes excessive noise. Excessive noise for snowmobiles manufactured after July 1, 1975, is a level of total snowmobile noise that exceeds 78 decibels measured on the A-weighted scale at 50 feet.” Turina showed slides of spectrograms from acoustic monitoring equipment depicting acoustic data from several national parks. Spikes occur when birds are singing in the morning or when helicopters fly overhead. Unexpectedly high levels can indicate sources of noise that need attention. HVAC systems in Yosemite, for example, caused high levels of noise in the middle of the night. At Mount Rushmore, maintenance personnel power washing the walkways caused a spike in noise. In a quiet location, Turina pointed out, noises like those generated by a chainsaw can travel great distances. “We’re dealing with a different kind of situation here where we have extremely low ambient noise levels,” he said. Ambient noise levels in the national parks, measured in decibels, can be in the teens or low 20s, levels that approach the threshold of human hearing. The topography and the season also influence how far noise carries, as several workshop participants pointed out. In discussing construction noise, Turina used as an example a breached irrigation ditch in Rocky Mountain National Park. The environmental impact statement for repairing the damage revealed that all of the construction equipment would be the same as that used in an urban setting, such as bulldozers, backhoes, and power tools. Similarly, retrofitting a fire tower in the backcountry of Glacier National Park required generators, drills, saws, grinders, and many other tools. “Providing parks with some guidance and tools for minimizing the noise that these things create is really important for us,” Turina said. Transportation noise, he explained, is generated by any equipment used primarily for moving people or equipment. The national parks have 110 transit systems, including systems operated by park concessionaires. Vehicles and transportation systems used by park personnel were included in the scope of the workshop, as were large-capacity tourist vehicles, but not recreational and private vehicles. Spectrograms reveal extensive noise from, for example, buses in the Grand Canyon. But Turina noted that in Zion National Park, a shuttle system installed 12 years ago to clear up a congested roadway has cut in half the percentage of time that vehicles are audible in some parts of the park, which suggests possibilities for improving transportation systems in general. A workshop participant commented on the debate about whether less noise for a longer period is preferable to more noise over a shorter period. The timing, duration, and amount of noise are all important, Turina answered. In addition, lower-frequency noise travels farther and is less subject to attenuation by vegetation and topography. Another participant observed that what people perceive can differ greatly from what they actually hear. Audibility protocols in the parks, Turina said, are based on an algorithm that enables researchers to determine audibility in real time through various methods. Trevino added that the metrics used by the Park Service to measure and characterize sounds are different from those used by other federal agencies because of the NPS mission to preserve natural and cultural resources. That is appropriate, said another workshop participant, because other standards are based on other factors, such as protecting human health. Also, what is unacceptable in one park might be acceptable in a different park where levels of background noise are higher. The Park Service was planning to work with the Volpe National Transportation Systems Center after the workshop to develop tools and strategies to minimize noise, Turina concluded. But every park is unique and each will need to consider how the recommendations could fit its situation. “We’re basically at step one,” he said. “We’re headed down the road to a systemwide program and guidance to help parks make these day-to-day decisions on how to reduce noise.” some of the most objectionable noises in national parks cited by workshop participants. Examples of Noise Challenges During the opening plenary session, Trevino invited the workshop participants to list the biggest noise challenges they have encountered in the national parks. They mentioned the following: Construction noises Overflights by helicopters and fixed-wing aircraft Other kinds of flights (e.g., search and rescue, maintenance) Vehicles, especially low-frequency noises from buses and trains and the distant “drone” of highway traffic Backup alarms on vehicles Motorcycles, especially those with modified exhaust systems Personal watercraft, snowmobiles, and airboats Lawn care equipment Generators, chainsaws, and other types of equipment Human-generated noise EFFECTS OF NOISE ON WILDLIFE1 Population growth, said Kurt Fristrup, senior scientist in the Natural Sounds and Night Skies Division, is projected to affect ambient noise levels. Population density is growing near the parks, and transportation noise is growing even faster than population. Data from the Department of Transportation show that over a period of time when population increased by 30 percent, sources of road and aircraft noise doubled and even tripled in some areas. In most areas of the United States, over half of all watersheds are within 380 meters of a road, making road traffic a common source of noise pollution nationwide. New natural gas exploration technologies will also bring noise to many previously quiet areas. Decades of research show that animal diversity and density tend to decrease near roadways, with the exception of a few (usually) invasive or exotic species. The dearth of wildlife near roadways could be due to factors other than roadway noise, but increasing evidence points to the importance of noise. For example, studies looking at energy exploration have found that noise has a significant impact on breeding birds—male sage grouse abandon areas where energy exploration creates noise. It is not clear whether animals interpret the noise as a threat or are simply reacting to the environmental degradation caused by noise. One experiment with collared elk found that they would move away from the sound of vehicles up to a kilometer away, but they were more likely to move when they were on a trail or road than if they were off the trail, which suggests that they were reacting to a perceived threat rather than the irritation of the noise. Mountain goats react to the sound of helicopters, which are often used in tagging the goats for wildlife research. Humpback whales show changes in their singing and interaction behaviors for up to three hours after a sonar event, and aircraft flying at low altitudes can disrupt behavior in ducks and other species for up to two hours afterward. Research has largely focused on the aversive reactions of wildlife to very loud noises. But chronic noise is also an issue, and Fristrup has advocated for research into the ecology around roadways to determine what the impact might be. Some animals have hearing thresholds at or below the quietest measured levels, and increases in chronic noise of just a few decibels could have a significant adverse effect. ________________ Some animals rely on sound when hunting prey, while others listen for warnings. The animals that rely most heavily on sound are probably more affected than others by increased noise, Fristrup said; predators generally have the most sensitive hearing among animals, enabling them to search the widest area. Owls have hearing sensitivity that is as much as 20 decibels better than humans, as do some bats. (One challenge in the field has been to develop microphones that can hear as well as some animals.) Animals use sound for purposes other than hunting. For example, migrating birds listen to sounds coming from the ground to decide where to stop, and many species of amphibians listen to wildlife calls to decide which ponds are suitable for breeding. Some animals may become habituated to noise, but that does not mean that it does not have an impact. Noise can change the breeding success of animals, both in the field and in the laboratory, or cause animals to miss a class of events that are important for them. Also, an animal subjected to a chronic stressor and then exposed to a second stressor may experience a more acute stress response than it would without the chronic stressor. This is an important area for additional research, Fristrup said, particularly as ambient noise levels increase. In response to a question, Fristrup noted that endangered species are treated the same as other species in considering the effects of noise, but the biology of each species must be taken into account. Tortoises, for example, may respond more to ground-borne vibration than to noise itself. EFFECTS OF NOISE ON PARK VISITORS2 Researchers have looked at the effects of noise on the people who visit national parks, Fristrup continued. Surveys of park visitors show that soundscapes are important to them, and research has found that scenery is more meaningful to people when there is less artificial noise. Lower noise levels also help visitors hear wildlife such as wolves, which are more likely to be heard than seen. Survey data further indicate that visitors are willing to help keep park areas quiet. At Muir Woods National Monument, for example, visitors observe quiet zones and quiet days when requested by posted signs (though they expressed more support for the quiet zone concept). ________________ On posted quiet days, visitors were significantly quieter than on other days. A “lost listening area” is an effective way to talk about a noise problem without mentioning decibels, Fristrup said, since many people do not have a good grasp of what decibels mean. (Overnight visitors also expressed concern about sleep interference, he said, but this issue has not been studied in parks.) Fristrup discussed the necessity of finding an appropriate metric when conducting noise research. The most commonly employed metrics use A-frequency weighting—a standard weighting curve that makes the metric generally representative of human hearing. But for some measurements, sampling should be limited to the frequencies most often produced by a particular source. In other cases, animals may have hearing sensitivities that differ from those of humans. As a workshop participant pointed out, whales have better low-frequency hearing than humans. In those cases, said Fristrup, using a human model may be inadvisable. However, humans have better low-frequency hearing than most other vertebrates, so an A-weighting curve is generally a conservative measurement. “[Human] hearing has also been extremely well studied,” he said. “Someone with healthy hearing can go out in the field and make observations that mean something.” Researchers sometimes measure the average noise level generated by a given source, but it is difficult to relate this measure to everyday experiences for the public. Knowing how often a noise is present and how loud it is helps with public education. A perceived loudness standard also may be preferable for higher noise levels. The question of noise metrics was also addressed by George Maling in his brief review of the Technology for a Quieter America report (NAE 2010). Citing the NAE report, Maling noted that human reactions to man-made and natural sounds differ, and that a different metric may be required for the assessment of noise impacts on wildlife. He also observed that the metric used to assess environmental noise depends on the source; for example, aircraft noise is assessed differently from highway noise. For the types of sources discussed at the workshop, the noise metrics will differ but have generally been defined for various noise sources. LOW-NOISE PRODUCTS IN THE NATIONAL PARKS Randy Stanley, an acoustic specialist for the National Park Service, concluded the plenary session by briefly discussing some NPS steps to procure low-noise products. The complication for the national parks is that the natural ambient sound level is the baseline against which impacts will be evaluated, but ambient levels vary greatly from one park to the next. Superintendents at each park are responsible for identifying what levels of noise constitute acceptable impacts, but they, too, face the problem of defining what is acceptable. One park may need to accommodate battlefield sounds, while at another even a single automobile may be inappropriate. In 2008 the Park Service began putting together information on how to reduce noise through low-noise products, using data from a Noise Pollution Clearinghouse (www.nonoise.org), the Consumers Union, and other sources. In 2009 an NPS guidance pamphlet was circulated to all the parks, with plans for updating over time (NPS 2011). The guidance recognizes that purchasers consider a wide variety of information when making decisions, including ease of use, power, flow rate, efficiency, weight, and engine design. At Glacier National Park, for example, large amounts of snow need to be removed from roadways each year, requiring the use of heavy equipment. And the lightweight chainsaws used by the Park Service (because they need to be carried long distances into the backcountry) are often noisier than others. Given such considerations, the pamphlet provides information on various strategies for making low-noise purchases. America's national parks provide a wealth of experiences to millions of people every year. What visitors see—landscapes, wildlife, cultural activities—often lingers in memory for life. And what they hear adds a dimension that sight alone cannot provide. Natural sounds can dramatically enhance visitors' experience of many aspects of park environments. In some settings, such as the expanses of Yellowstone National Park, they can even be the best way to enjoy wildlife, because animals can be heard at much greater distances than they can be seen. Sounds can also be a natural complement to natural scenes, whether the rush of water over a rocky streambed or a ranger's explanation of a park's history. In other settings, such as the New Orleans Jazz National Historical Park, sounds are the main reason for visiting a park. The acoustical environment is also important to the well-being of the parks themselves. Many species of wildlife depend on their hearing to find prey or avoid predators. If they cannot hear, their survival is jeopardized—and the parks where they live may in turn lose part of their natural heritage. For all these reasons it is important to be aware of noise (defined as unwanted sound, and in this case usually generated by humans or machinery), which can degrade the acoustical environment, or soundscape, of parks. Just as smog smudges the visual horizon, noise obscures the listening horizon for both visitors and wildlife. This is especially true in places, such as remote wilderness areas, where extremely low sound levels are common. The National Park Service (NPS) has determined that park facilities, operations, and maintenance activities produce a substantial portion of noise in national parks and thus recognizes the need to provide park managers with guidance for protecting the natural soundscape from such noise. Therefore, the focus of the workshop was to define what park managers can do to control noise from facilities, operations, and maintenance, and not on issues such as the effects of noise on wildlife, noise metrics, and related topics. To aid in this effort, NPS joined with the National Academy of Engineering (NAE) and with the US Department of Transportation's John A. Volpe National Transportation Systems Center to hold a workshop to examine the challenges and opportunities facing the nation's array of parks. Entitled "Protecting National Park Soundscapes: Best Available Technologies and Practices for Reducing Park- Generated Noise," the workshop took place October 3-4, 2012, at NPS's Natural Resource Program Center in Fort Collins, Colorado.

[treeswarper]

If I want guaranteed ('cept for airplanes and critters) quiet, I head for non-wilderness places like tree plantations or just a patch of woods. You generally won't see any people and contrary to some opinions and can still see a goodly amount of wildlife if you are skilled at being stealthy. It's out there and is not glorious or "epic" enough to attract anybody. I would avoid a National Park. In fact, you can find quiet on motorized trails around here if you go hike them on weekdays and avoid the most popular ones. Motorized is a designation, it does not mean always noisy. Just beware of total quiet. When birds and little critters go silent, something is afoot, be it a predator or an earthquake.

[Chief Joseph]

Live and let live..... and prosecute those who cause destruction to the fullest extent of the law, or maybe push them off a cliff, lol.

[Randito]

[Ski]

re: the URL Randy posted just above: Supposedly the "quietest place on earth", because the Hoh is a more frequently visited river valley than the one immediately south of it, so the fighter jets from Whidbey fly over the Queets all afternoon long. So while the lip service that the National Park Service gives to "soundscapes" might evoke visions of unicorns and fairies prancing amidst uncompromised virgin rain forest, they have absolutely no control over, or influence on, the Department of Defense, which indefensibly continues to use the airspace over a National Park for their aerial acrobatics day after day after day after day after day after day after day after day. All day long. Every day.

[MtnGoat]

Which mountain range are you OK with them using for training?

[Schenk]

[Ski]

^ Somewhere OTHER than the airspace over a National Park, especially when there are other options available that are already used for that purpose. Of course, I'm sure there are those who believe that military jet aircraft practice is perfectly appropriate over the Grand Canyon, Yosemite, Yellowstone, and other NPS facilities, right? It is an inappropriate and indefensible use of the airspace over a National Park.